@article{BARRIAS2025111036,

title = {Newly developed QCM-DNA biosensor for SNP detection in small DNA fragments: A wine authenticity case study},

author = {Sara Barrias and José R. Fernandes and Paula Martins-Lopes},

url = {https://www.sciencedirect.com/science/article/pii/S0956713524007539},

doi = {https://doi.org/10.1016/j.foodcont.2024.111036},

issn = {0956-7135},

year  = {2025},

date = {2025-03-01},

urldate = {2025-03-01},

journal = {Food Control},

volume = {169},

pages = {111036},

abstract = {We propose a QCM-DNA biosensor for single nucleotide polymorphism (SNP) detection in samples of differing complexity. An optimized protocol is presented, focusing on parameters affecting probe immobilization and hybridization efficiency. Our results led to the implementation of thiolated probe reduction with TCEP, followed by immobilization in PBS buffer containing MgCl2. The biosensor exhibited an enhanced specificity at 37 °C, achieving detection of single mismatches using synthetic targets. Using real samples, we applied the biosensor in a wine authenticity assessment context. The addition of dithiothreitol improved stability and reproducibility when testing wine DNA samples. The QCM-DNA biosensor was able to specifically detect complementary DNA in leaf and wine DNA samples, distinguishing between samples with two heterozygous mismatches. The biosensor solely depends on DNA extraction, basic instrumentation, and reagents, without requiring PCR or signal amplification strategies. Our findings show the biosensor potential for applications in wine authenticity assessment and other fields requiring complex analysis in undemanding settings.},

keywords = {Aptamer, DNA, Grapevine, Microbalance, openQCM Q-1, Piezoelectric, QCM-D, Quartz Crystal Microbalance, SNP, Wine},

pubstate = {published},

tppubtype = {article}

}

@article{malhotra2025quantification,

title = {Quantification of Methane in Water at Parts Per Billion Sensitivity Using a Metal–Organic Framework-Functionalized Quartz Crystal Resonator},

author = {Jaskaran Singh Malhotra and Clara Dávila Duarte and Per Reichert and Deepthy Krishnan and Jonas Sundberg},

url = {https://pubs.acs.org/doi/abs/10.1021/acsanm.4c06883},

doi = {https://doi.org/10.1021/acsanm.4c06883},

year  = {2025},

date = {2025-02-26},

urldate = {2025-02-26},

journal = {ACS Applied Nano Materials},

publisher = {ACS Publications},

abstract = {Wetlands and water bodies are essential sources of methane emissions, a greenhouse gas that is roughly 25 times more potent than carbon dioxide. However, the biological production, fluxes, and interplay between methane and carbon dioxide due to microbial activity must be better understood. This is primarily attributed to the lack of sensor technology to provide the required spatial and temporal resolution. Herein, we demonstrate how a porous metal–organic framework material can create a sensor to quantify dissolved methane. The sensor is based on a quartz crystal microbalance, which measures methane adsorption using a quartz resonator functionalized with the material. Combining the quartz crystal microbalance and the nanoporous material yields fast response times and high sensitivity. This is due to a favorable partitioning coefficient between the empty pores of the material and the aqueous phase, promoting rapid migration of dissolved methane into the material. The result is a sensor system that achieves equilibration and response times under 60 s with parts per billion sensitivity. The high sensor performance is based on microporous pore size distribution, surface hydrophobicity, and crystallite size, yielding strong synergy. A fully functioning prototype has been designed, built, and evaluated to demonstrate real-life applicability and obtain a response from methane-spiked lake water. The modular nature of metal–organic frameworks opens possibilities for creating materials for selective sensing of other aqueous species. Thus, our study showcases the importance of materials for methane sensing and environmental monitoring in general.},

keywords = {chemical sensors, greenhouse gas emissions, hydrocarbons, Metal organic frameworks, methane monitoring, openQCM NEXT, QCM, Quartz Crystal Microbalance, Thin films, wetlands},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/5.0242516,

title = {The fabrication of PVP/NiAc nanofiber as a QCM active layer for hazardous vapor detection},

author = {Riris Sukowati and Yadi Mulyadi Rohman and Bertolomeus Haryanto Agung and Aan Priyanto and Dian Ahmad Hapidin and Khairurrijal Khairurrijal},

url = {https://doi.org/10.1063/5.0242516},

doi = {10.1063/5.0242516},

issn = {0094-243X},

year  = {2025},

date = {2025-02-20},

urldate = {2025-01-01},

journal = {AIP Conference Proceedings},

volume = {3197},

number = {1},

pages = {020002},

abstract = {The detection of hazardous vapors is crucial for controlling their pollution in the environment. The Quartz crystal microbalance (QCM) stands out as a high-performance sensing device that features high sensitivity, simplicity, low cost, and the ability to operate at room temperature. In this study, a QCM has been coated with a new active layer of PVP/NiAc composite nanofibers to detect hazardous vapor. The QCM surface is coated with PVP/NiAC nanofiber which is fabricated using the electrospinning method. The morphology and average diameter of PVP/NiAc composite nanofibers were investigated utilizing an optical microscope and ImageJ software, respectively. The developed composite nanofibers have an average diameter of 989 ± 172.61 nm. The fabricated sensor was tested against methanol, acetone, dimethylacetamide (DMAc), and formaldehyde vapors in different concentrations ranging from 5.0 to 22.5 ppm. The sensitivities of QCM sensors with PVP/NiAc nanofiber active layer were 2.35, 0.62, 0.32, and 0.29 Hz/ppm for methanol, formaldehyde, acetone, and DMAc, respectively. The developed sensor performed the highest sensitivity and frequency shift response in detecting methanol vapors. Furthermore, the adsorption phenomena were investigated by adapting several adsorption models, including Scatchard, Freundlich, Langmuir, and Langmuir–Freundlich, to validate the physical adsorption affinity. In conclusion, the QCM sensors based on PVP/NiAc composite nanofibers can be a considerable way to detect hazardous vapors, especially methanol, in various sensing applications.},

keywords = {Electrospinning, Nanofiber, openQCM, Physisorption, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{Obořilová2025,

title = {Piezoelectric biosensor with dissipation monitoring enables the analysis of bacterial lytic agent activity},

author = {Radka Obořilová and Eliška Kučerová and Tibor Botka and Hana Vaisocherová-Lísalová and Petr Skládal and Zdeněk Farka},

url = {https://doi.org/10.1038/s41598-024-85064-x},

doi = {10.1038/s41598-024-85064-x},

issn = {2045-2322},

year  = {2025},

date = {2025-01-27},

urldate = {2025-01-27},

journal = {Nature - Scientific Reports},

volume = {15},

number = {1},

pages = {3419},

abstract = {Antibiotic-resistant strains of Staphylococcus aureus pose a significant threat in healthcare, demanding urgent therapeutic solutions. Combining bacteriophages with conventional antibiotics, an innovative approach termed phage-antibiotic synergy, presents a promising treatment avenue. However, to enable new treatment strategies, there is a pressing need for methods to assess their efficacy reliably and rapidly. Here, we introduce a novel approach for real-time monitoring of pathogen lysis dynamics employing the piezoelectric quartz crystal microbalance (QCM) with dissipation (QCM-D) technique. The sensor, a QCM chip modified with the bacterium S. aureus RN4220 ΔtarM, was utilized to monitor the activity of the enzyme lysostaphin and the phage P68 as model lytic agents. Unlike conventional QCM solely measuring resonance frequency changes, our study demonstrates that dissipation monitoring enables differentiation of bacterial growth and lysis caused by cell-attached lytic agents. Compared to reference turbidimetry measurements, our results reveal distinct alterations in the growth curve of the bacteria adhered to the sensor, characterized by a delayed lag phase. Furthermore, the dissipation signal analysis facilitated the precise real-time monitoring of phage-mediated lysis. Finally, the QCM-D biosensor was employed to evaluate the synergistic effect of subinhibitory concentrations of the antibiotic amoxicillin with the bacteriophage P68, enabling monitoring of the lysis of P68-resistant wild-type strain S. aureus RN4220. Our findings suggest that this synergy also impedes the formation of bacterial aggregates, the precursors of biofilm formation. Overall, this method brings new insights into phage-antibiotic synergy, underpinning it as a promising strategy against antibiotic-resistant bacterial strains with broad implications for treatment and prevention.},

keywords = {Antimicrobial treatment, Bacteriophages, biosensors, Multidrug-resistant bacteria, openQCM Q-1, Phage therapy, Phage-antibiotic synergy, Piezoelectric biosensor, QCM, QCM-D, Quartz Crystal Microbalance, Staphylococcus aureus},

pubstate = {published},

tppubtype = {article}

}

@article{ahamed5094062elliptical,

title = {Elliptical Electrode Designs in Quartz Crystal Microbalances: Enhancing Sensitivity in Liquid Biosensing Applications},

author = {Afri Ahamed and Chien Wei Ooi and Hui Jean Lim and N Ramakrishnan and Tridib Saha},

url = {https://papers.ssrn.com/sol3/papers.cfm?abstract_id=5094062},

doi = {https://dx.doi.org/10.2139/ssrn.5094062},

year  = {2025},

date = {2025-01-11},

urldate = {2025-01-11},

journal = {Available at SSRN 5094062},

abstract = {The demand for highly sensitive and versatile sensors is rapidly growing in biomedical applications, where specific, sensitive, and rapid detection are essential. Quartz crystal microbalance (QCM) is a popular analytical tool for such applications due to its high sensitivity and real-time monitoring capabilities. However, conventional QCM-based biosensing assays often suffer from poor sensitivity and high sample consumption, limiting their practicality. This study introduces a modified electrode design and a single droplet-based assay to enhance QCM-based bio-detection. Through extensive experiments, including contact angle analysis, damping, and viscosity measurements, we identified an optimal elliptical electrode design for single droplet-based liquid sensing. Using QCM crystals coated with molecularly imprinted polydopamine (MIPDA) sensing films containing recognition sites for detecting pepsin as a model protein, we demonstrate that QCM crystals with elliptical electrodes exhibit up to 10 times higher sensitivity than the industry-standard 1-inch circular QCM crystal. Additionally, the optimized QCM crystals showed linear sensitivity over a wider volume range, providing consistent detection at 250 Hz/μl compared to the circular crystal's narrower range at 50 Hz/μl. These findings establish a foundation for next-generation QCM platforms with superior sensitivity, reduced sample requirements, and broader adaptability, paving the way for advancements in biomedical diagnostics and environmental monitoring.},

keywords = {Deionised Water, DI Water, Elliptical Electrodes, Liquid Droplet Detection, openQCM Q-1, Protein Sensing, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{as2024investigation,

title = {Investigation of the Multiple Doping of Citric Acid and Chitosan in Nanofiber for Enhancement of a Quartz Crystal Microbalance-Based Ammonia Sensor},

author = {Ahmad Hasan As’ ari and Rizky Aflaha and Laila Katriani and Ahmad Kusumaatmaja and Rike Yudianti and Kuwat Triyana},

url = {https://link.springer.com/article/10.1007/s11664-024-11646-0},

doi = {https://doi.org/10.1007/s11664-024-11646-0},

year  = {2024},

date = {2024-12-19},

urldate = {2024-12-19},

journal = {Journal of Electronic Materials},

pages = {1--13},

publisher = {Springer},

abstract = {Herein, the use of multiple doping of citric acid (CA) and chitosan (CS) in polyacrylonitrile (PAN) nanofibers over a quartz crystal microbalance is investigated as a method for enhancing the performance of an ammonia sensor at room temperature. It was found that the PAN/CA/CS sensor has superior sensitivity and better selectivity. The PAN/CA/CS sensor demonstrated sensitivity of (0.629 ± 0.005) Hz ppm−1, which increased by 2.75 times compared to the PAN/CA sensor and 39 times compared to the PAN sensor. Chitosan doping also resulted in better selectivity, as shown by the decreased response of the PAN/CA/CS sensor compared to the PAN/CA sensor to other analytes including formaldehyde (−147%), acetic acid (−22%), ethanol (−19%), methanol (−15%), and acetone (−1%). The viscoelastic properties of chitosan might be responsible for the anti-Sauerbrey phenomena behind the enhanced selectivity. The detection and adsorption mechanisms of the fabricated sensors towards ammonia were studied using adsorption kinetics and isotherms. The adsorption kinetics varied and exhibited the limits of the high-concentration region of each sensor. Moreover, all the fabricated sensors followed the Freundlich adsorption isotherm with different adsorption processes, which were confirmed by scanning electron microscopy, x-ray diffraction, and Fourier transform infrared spectroscopy concerning the morphology, crystal structure, and active groups after the loading of citric acid and chitosan. Thus, the use of multiple doping can improve the sensor abilities, as well as causing changes in the detection and adsorption mechanisms.},

keywords = {Adsorption, Ammonia, Chitosan, Nanofiber, openQCM, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{dedecker2025selective,

title = {Selective Adsorption and Separation of C 6 Hydrocarbons: The Role of Structural Flexibility and Functionalization in Zeolitic Imidazolate Frameworks},

author = {Kevin Dedecker and Martin Drobek and Anne Julbe},

url = {https://pubs.rsc.org/en/content/articlehtml/2025/lf/d4lf00388h},

doi = {https://doi.org/10.1039/D4LF00388H},

year  = {2024},

date = {2024-12-19},

urldate = {2024-12-19},

journal = {RSC Applied Interfaces},

publisher = {Royal Society of Chemistry},

abstract = {This study investigates the selective adsorption and separation of C6 hydrocarbons (benzene, cyclohexane, and n-hexane) by zeolitic imidazolate frameworks (ZIFs), focusing on their structural flexibility and functionalization. ZIF-8_CH3 and ZIF-8_Br were synthesized and compared, indicating distinct adsorption behaviors. ZIF-8_CH3 showed higher uptake for benzene (9.5 molecules per unit cell) and n-hexane (8.0 mlc uc−1) compared to cyclohexane (1.0 mlc uc−1). In contrast, ZIF-8_Br exhibited enhanced adsorption for cyclohexane (5.0 mlc uc−1) and reduced n-hexane uptake (0.5 mlc uc−1). Computational simulations supported these findings, identifying the involved host–guest interactions. Ideal adsorbed solution theory analysis confirmed that ZIF-8_CH3 demonstrated virtually zero uptake of cyclohexane from binary mixtures containing either n-hexane or benzene, while ZIF-8_Br exhibited negligible adsorption of n-hexane from its mixtures with cyclohexane or benzene. It was concluded that bromine functionalization in ZIF-8_Br increased structural rigidity and selectivity for aromatic compounds. These results highlight the crucial role of functionalization and gate-opening phenomena in ZIFs to achieve efficient volatile organic compound capture and separation where traditional adsorbents may not be effective.},

keywords = {Adsorption, benzene, cyclohexane, hydrocarbons, n-hexane, openQCM, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{D4AY01859A,

title = {A polyaniline-enhanced quartz crystal microbalance sensor for room-temperature camphor detection},

author = {Rizky Aflaha and Muammar Romiz Dzaki and Laila Katriani and Ahmad Hasan As'ari and Chlara Naren Maharani and Agus Kuncaka and Taufik Abdillah Natsir and Aditya Rianjanu and Ruchi Gupta and Kuwat Triyana and Roto Roto},

url = {http://dx.doi.org/10.1039/D4AY01859A},

doi = {10.1039/D4AY01859A},

year  = {2024},

date = {2024-12-18},

urldate = {2025-01-01},

journal = {Anal. Methods},

pages = {-},

publisher = {The Royal Society of Chemistry},

abstract = {A method to detect camphor gas is considered indispensable in the pharmaceutical industry. Unfortunately, the available sensors to detect the presence of camphor in the air are very limited and still on a laboratory scale, such as using chromatography-mass spectroscopy (GC-MS). The research's main focus is to obtain a portable sensing system with excellent sensitivity and selectivity. This study explored polyaniline (PANi) concentrations cast over PVAc nanofiber as a matrix to detect camphor gas using a quartz crystal microbalance (QCM) system to measure camphor exposure. Scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) were used to analyze the morphology and chemical composition of the fabricated active layer (i.e., nanofiber with PANi thin film). Increasing the PANi concentration provides more PANi on the sensor surface, thus amassing the active groups to interact with camphor gas molecules. It shows that a sensor with a 0.08% PANi thin film (Nano-PANi8) has a sensitivity of 2.594 Hz ppm−1, much greater than the sensor without PANi, which is only 0.305 Hz ppm−1. In addition, the sensor also has good repeatability and rapid response and recovery time of 47 s and 133 s, respectively. Compared to other gaseous compounds, the sensor also has excellent selectivity for camphor and robust long-term stability over three weeks of testing. The produced QCM sensor employing PANi thin film can give a camphor sensor superior performance, including excellent sensitivity, selectivity, and long-term stability. Furthermore, the use of QCM as a base sensor also makes the fabricated sensor portable.},

keywords = {chromatography-mass spectroscopy, openQCM, PANi thin film, Polyaniline, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{hunter2024covalent,

title = {Covalent Capture of Nanoparticle-Stabilized Oil Droplets via Acetal Chemistry Using a Hydrophilic Polymer Brush},

author = {Saul J Hunter and Evelin Csányi and Joshua JS Tyler and Mark A Newell and Matthew AH Farmer and Camery Ma and George Sanderson and Graham J Leggett and Edwin C Johnson and Steven P Armes},

url = {https://pubs.acs.org/doi/full/10.1021/acs.langmuir.4c03897},

doi = {https://doi.org/10.1021/acs.langmuir.4c03897},

year  = {2024},

date = {2024-12-06},

urldate = {2024-01-01},

journal = {Langmuir},

publisher = {ACS Publications},

abstract = {We report the capture of nanosized oil droplets using a hydrophilic aldehyde-functional polymer brush. The brush was obtained via aqueous ARGET ATRP of a cis-diol-functional methacrylic monomer from a planar silicon wafer. This precursor was then selectively oxidized using an aqueous solution of NaIO4 to introduce aldehyde groups. The oil droplets were prepared by using excess sterically stabilized diblock copolymer nanoparticles to prepare a relatively coarse squalane-in-water Pickering emulsion (mean droplet diameter = 20 μm). This precursor was then further processed via high-pressure microfluidization to produce ∼200 nm squalane droplets. We demonstrate that adsorption of these nanosized oil droplets involves acetal bond formation between the cis-diol groups located on the steric stabilizer chains and the aldehyde groups on the brush. This interaction occurs under relatively mild conditions and can be tuned by adjusting the solution pH. Hence this is a useful model system for understanding oil droplet interactions with soft surfaces.},

keywords = {Adsorption, lipids, Liquids, Nanoemulsions, nanoparticles, openQCM NEXT, QCM, QCM-D, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{DATTILO2024114408,

title = {Molecularly Imprinted Polymers (MIPs) for SARS-CoV-2 Omicron variant inhibition: an alternative approach to address the challenge of emerging zoonoses},

author = {Marco Dattilo and Francesco Patitucci and Marisa Francesca Motta and Sabrina Prete and Roberta Galeazzi and Silvia Franzè and Ida Perrotta and Mariangela Cavarelli and Ortensia Ilaria Parisi and Francesco Puoci},

url = {https://www.sciencedirect.com/science/article/pii/S0927776524006672},

doi = {https://doi.org/10.1016/j.colsurfb.2024.114408},

issn = {0927-7765},

year  = {2024},

date = {2024-11-26},

urldate = {2024-01-01},

journal = {Colloids and Surfaces B: Biointerfaces},

pages = {114408},

abstract = {ABSTRACT 

Emerging zoonoses pose significant public health risks and necessitate rapid and effective treatment responses. This study enhances the technology for preparing Molecularly Imprinted Polymers (MIPs), which function as synthetic nanoparticles targeting SARS-CoV-2 receptor-binding domain (RBD), specifically the Omicron variant, thereby inhibiting its function. This study builds on previous findings by introducing precise adjustments in the formulation and process conditions to enhance particle stability and ensure better control over size and distribution, thereby overcoming the issues identified in earlier research. Following docking studies, imprinted nanoparticles were synthesized via inverse microemulsion polymerization and characterized in terms of size, morphology and surface charge. The selective recognition properties and ability of MIPs to obstruct the interaction between ACE2 and the RBD of SARS-CoV-2 were assessed in vitro, using Non-Imprinted Polymers (NIPs) as controls, and rebinding studies were conducted utilizing a Quartz Crystal Microbalance with Dissipation monitoring (QCM-D). The synthesized nanoparticles exhibited uniform dispersion and had a consistent diameter within the nanoscale range. MIPs demonstrated significant recognition properties and exhibited a concentration-dependent ability to reduce RBD binding to ACE2 without cytotoxic or sensitizing effects. MIPs-based platforms offer a promising alternative to natural antibodies for treating SARS-CoV-2 infections, therefore representing a versatile platform for managing emerging zoonoses.},

keywords = {Emulsion Polymerization, Molecular Recognition, Molecularly Imprinted Polymers (MIPs), Omicron Variant, openQCM NEXT, QCM, Quartz Crystal Microbalance, SARS-CoV-2, Spike Protein Receptor-Binding Domain (RBD)},

pubstate = {published},

tppubtype = {article}

}

@article{wang2024enhancing,

title = {Enhancing the Pressure-Sensitive Electrical Conductance of Self-Assembled Monolayers},

author = {Xintai Wang and Asma Alajmi and Zhangchenyu Wei and Mohammed Alzanbaqi and Naixu Wei and Colin Lambert and Ali Ismael},

url = {https://pubs.acs.org/doi/full/10.1021/acsami.4c15796},

doi = {https://doi.org/10.1021/acsami.4c15796},

year  = {2024},

date = {2024-11-19},

urldate = {2024-01-01},

journal = {ACS Applied Materials & Interfaces},

publisher = {ACS Publications},

abstract = {The inherent large HOMO–LUMO gap of alkyl thiol (CnS) self-assembled monolayers (SAMs) has limited their application in molecular electronics. This work demonstrates significant enhancement of mechano-electrical sensitivity in CnS SAMs by external compression, achieving a gauge factor (GF) of approximately 10 for C10S SAMs. This GF surpasses values reported for conjugated wires and DNA strands, highlighting the potential of CnS SAMs in mechanosensitive devices. Conductive atomic force microscopy (cAFM) investigations reveal a strong dependence of GF on the alkyl chain length in probe/CnS/Au junctions. This dependence arises from the combined influence of molecular tilting and probe penetration, facilitated by the low Young’s modulus of alkyl chains. Theoretical simulations corroborate these findings, demonstrating a shift in the electrode Fermi level toward the molecular resonance region with increasing chain length and compression. Introducing a rigid graphene interlayer prevents probe penetration, resulting in a GF that is largely independent of the alkyl chain length. This highlights the critical role of probe penetration in maximizing mechano-electrical sensitivity. These findings pave the way for incorporating CnS SAMs into mechanosensitive and mechanocontrollable molecular electronic devices, including touch-sensitive electronic skin and advanced sensor technologies. This work demonstrates the potential of tailoring mechanical and electrical properties of SAMs through molecular engineering and interface modifications for optimized performance in specific applications.},

keywords = {AFM, Atomic Force Microscopy, Gauge factor, openQCM, Penetration, QCM, Quartz Crystal Microbalance, Self-Assembled Monolayers (SAMs), Tunnelling decay},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/adfm.202414687,

title = {Acoustic Fingerprinting and Nanoslip Dynamics of Biofilms},

author = {Saikat Jana and Nikhil Bhalla},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202414687},

doi = {https://doi.org/10.1002/adfm.202414687},

year  = {2024},

date = {2024-11-12},

journal = {Advanced Functional Materials},

volume = {n/a},

number = {n/a},

pages = {2414687},

abstract = {Abstract It is reported that bacteria can generate nanomotion, but understanding the complex dynamics of bacterial colony gliding on solid interfaces has remained unresolved. Here, this work captures the real-time development and gliding of bacterial biofilms on vibrating solids made of piezoelectric quartz. The gliding, characterized by liquid slips, is measured in form of frequency and dissipation changes of the vibrating solid. These vibrations enable the generation of distinct acoustic fingerprints (sound/ music) of the three phases of biofilm development: viscoelastic strengthening, biofilm growth and biofilm stability. In adition, the effect of extracellular matrix secretion on the rigidity of the film and its nanoslip in each of the distinct biofilm developmental phases is quantified. This work provides a real-time, label-free method of quantifying bacteria biofilm dynamics and paves the way for developing libraries of acoustic signatures of bacteria and their metabolic products.},

keywords = {acoustics, bacteria-music, biofilms, mutation, openQCM NEXT, QCM-D, Quartz Crystal Microbalance, vibrating-solids},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1002/adma.202409248,

title = {Long-Range Proton Channels Constructed via Hierarchical Peptide Self-Assembly},

author = {Semion Censor and Jorge Vega Martin and Ohad Silberbush and Samala Murali Mohan Reddy and Ran Zalk and Lonia Friedlander and Daniel G. Trabada and Jesús Mendieta and Guillaume Le Saux and Jesús Ignacio Mendieta Moreno and Linda Angela Zotti and José Ortega Mateo and Nurit Ashkenasy},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202409248},

doi = {https://doi.org/10.1002/adma.202409248},

year  = {2024},

date = {2024-11-12},

journal = {Advanced Materials},

volume = {n/a},

number = {n/a},

pages = {2409248},

abstract = {Abstract The quest to understand and mimic proton translocation mechanisms in natural channels has driven the development of peptide-based artificial channels facilitating efficient proton transport across nanometric membranes. It is demonstrated here that hierarchical peptide self-assembly can form micrometers-long proton nanochannels. The fourfold symmetrical peptide design leverages intermolecular aromatic interactions to align self-assembled cyclic peptide nanotubes, creating hydrophilic nanochannels between them. Titratable amino acid sidechains are positioned adjacent to each other within the channels, enabling the formation of hydrogen-bonded chains upon hydration, and facilitating efficient proton transport. Moreover, these chains are enriched with protons and water molecules by interacting with immobile counter ions introduced into the channels, increasing proton flow density and rate. This system maintains proton transfer rates closely resembling those in natural protein channels over micrometer distances. The functional behavior of these inherently recyclable and biocompatible systems opens the door for their exploitation in diverse applications in energy storage and conversion, biomedicine, and bioelectronics.},

keywords = {Dissipation, molecular dynamic simulations, openQCM Q-1, peptides, proton channels, proton transport, QCM-D, Quartz Crystal Microbalance, self-assembly},

pubstate = {published},

tppubtype = {article}

}

@article{maity2024steering,

title = {Steering diffusion selectivity of chemical isomers within aligned nanochannels of metal-organic framework thin film},

author = {Tanmoy Maity and Susmita Sarkar and Susmita Kundu and Suvendu Panda and Arighna Sarkar and Raheel Hammad and Kalyaneswar Mandal and Soumya Ghosh and Jagannath Mondal and Ritesh Haldar},

url = {https://www.nature.com/articles/s41467-024-53207-3#citeas},

doi = {https://doi.org/10.1038/s41467-024-53207-3},

year  = {2024},

date = {2024-11-08},

urldate = {2024-11-08},

journal = {Nature Communications},

volume = {15},

number = {1},

pages = {1--9},

publisher = {Nature Publishing Group},

abstract = {The movement of molecules (i.e. diffusion) within angstrom-scale pores of porous materials such as metal-organic frameworks (MOFs) and zeolites is influenced by multiple complex factors that can be challenging to assess and manipulate. Nevertheless, understanding and controlling this diffusion phenomenon is crucial for advancing energy-economic membrane-based chemical separation technologies, as well as for heterogeneous catalysis and sensing applications. Through precise assessment of the factors influencing diffusion within a porous metal-organic framework (MOF) thin film, we have developed a chemical strategy to manipulate and reverse chemical isomer diffusion selectivity. In the process of cognizing the molecular diffusion within oriented, angstrom-scale channels of MOF thin film, we have unveiled a dynamic chemical interaction between the adsorbate (chemical isomers) and the MOF using a combination of kinetic mass uptake experiments and molecular simulation. Leveraging the dynamic chemical interactions, we have reversed the haloalkane (positional) isomer diffusion selectivity, forging a chemical pathway to elevate the overall efficacy of membrane-based chemical separation and selective catalytic reactions.},

keywords = {chemical isomers, Diffusion Selectivity, metal-organic frameworks, Molecular Separation, Nano Channels, openQCM, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{FORINOVA2024110695b,

title = {A reusable QCM biosensor with stable antifouling nano-coating for on-site reagent-free rapid detection of E. coli O157:H7 in food products},

author = {Michala Forinová and Alina Pilipenco and N. Scott Lynn and Radka Obořilová and Hana Šimečková and Markéta Vrabcová and Monika Spasovová and Rachael Jack and Petr Horák and Milan Houska and Petr Skládal and Petr Šedivák and Zdeněk Farka and Hana Vaisocherová-Lísalová},

url = {https://www.sciencedirect.com/science/article/pii/S0956713524004122},

doi = {https://doi.org/10.1016/j.foodcont.2024.110695},

issn = {0956-7135},

year  = {2024},

date = {2024-11-01},

urldate = {2024-11-15},

journal = {Food Control},

volume = {165},

pages = {110695},

abstract = {Numerous biosensors have shown exceptional analytical performance under laboratory conditions, yet only a few are capable of on-site use with complex, non-model samples while exhibiting reliable analytical performance. Here, we present a new portable biosensor for the rapid (30 min) and accurate detection of bacterial agents in “real-world” food samples, which are originally in either solid or liquid form. The biosensor combines well-established quartz crystal microbalance (QCM) technology, with innovative terpolymer brush nano-coatings on the sensing surface to efficiently reduce non-specific fouling from food samples. Following reagent-free sample preparation, where solid food samples are homogenized, we validated the sensor's detection capabilities on native pathogenic Escherichia coli O157:H7 (E. coli O157:H7) in hamburgers, Czech dumplings, and milk. We achieved limits of detection (LOD), as low as 7.5 × 102 CFU/mL in milk, a value approaching fundamental QCM limits, using a simple direct detection assay format. The biosensor's exceptional reusability was demonstrated through 60 sequential hamburger sample injections, resulting in only a minor LOD shift toward the end of series. A 10-min sonication treatment during sample preparation significantly enhanced sensitivity for E. coli O157:H7 in hamburgers and dumplings, yielding LODs as low as 3.1 × 10³ CFU/mL and 2.6 × 10⁴ CFU/mL, respectively. For on-site analysis, we integrated the nano-coated sensing chip into a custom-built four-channel portable QCM biosensor with an optimized microfluidic system, which can be produced on a scale suitable for practical deployment.},

keywords = {Antifouling coating, O157:H7 detection, On-site analysis, openQCM Q-1, QCM, QCM biosensor, Quartz Crystal Microbalance, Reusability},

pubstate = {published},

tppubtype = {article}

}

@article{baruah2024point,

title = {Point of care devices for detection of Covid-19, malaria and dengue infections: A review},

author = {Susmita Baruah and CA Betty},

url = {https://www.sciencedirect.com/science/article/abs/pii/S1567539424000665},

doi = {https://doi.org/10.1016/j.bioelechem.2024.108704},

year  = {2024},

date = {2024-08-01},

urldate = {2024-08-01},

journal = {Bioelectrochemistry},

pages = {108704},

publisher = {Elsevier},

abstract = {Need for affordable, rapid and user-friendly point of care (POC) devices are increasing exponentially for strengthening the health care system in primary care as well as for self- monitoring in routine analysis. In addition to routine analysis of glucose, Covid-19 type fast spreading, infectious diseases have created further push for exploring rapid, cost-effective and self-monitoring diagnostic devices. Successful implementation of self-monitoring devices for Covid −19 has been realized. However, not much success has been realized for malaria and dengue which are two fatal diseases that affect the population in underdeveloped and developing countries. To monitor the presence of parasites for these diseases, rapid, onsite monitoring devices are still being explored. In this review, we present a review of the research carried out on electrochemical POC devices for monitoring infectious diseases such as Covid-19, malaria and dengue.



},

keywords = {Covid −19, Dengue, openQCM, POC diagnostic devices, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{karchilakis2024capturing,

title = {Capturing Enzyme-Loaded Diblock Copolymer Vesicles Using an Aldehyde-Functionalized Hydrophilic Polymer Brush},

author = {Georgios Karchilakis and Spyridon Varlas and Edwin C Johnson and Oleta Norvilaite and Matthew AH Farmer and George Sanderson and Graham J Leggett and Steven P Armes},

url = {https://pubs.acs.org/doi/full/10.1021/acs.langmuir.4c01561},

doi = {https://doi.org/10.1021/acs.langmuir.4c01561},

year  = {2024},

date = {2024-06-27},

urldate = {2024-06-27},

journal = {Langmuir},

publisher = {ACS Publications},

abstract = {Compared to lipids, block copolymer vesicles are potentially robust nanocontainers for enzymes owing to their enhanced chemical stability, particularly in challenging environments. Herein we report that cis-diol-functional diblock copolymer vesicles can be chemically adsorbed onto a hydrophilic aldehyde-functional polymer brush via acetal bond formation under mild conditions (pH 5.5, 20 °C). Quartz crystal microbalance studies indicated an adsorbed amount, Γ, of 158 mg m–2 for vesicle adsorption onto such brushes, whereas negligible adsorption (Γ = 0.1 mg m–2) was observed for a control experiment conducted using a cis-diol-functionalized brush. Scanning electron microscopy and ellipsometry studies indicated a mean surface coverage of around 30% at the brush surface, which suggests reasonably efficient chemical adsorption. Importantly, such vesicles can be conveniently loaded with a model enzyme (horseradish peroxidase, HRP) using an aqueous polymerization-induced self-assembly formulation. Moreover, the immobilized vesicles remained permeable toward small molecules while retaining their enzyme payload. The enzymatic activity of such HRP-loaded vesicles was demonstrated using a well-established colorimetric assay. In principle, this efficient vesicle-on-brush strategy can be applied to a wide range of enzymes and functional proteins for the design of next-generation immobilized nanoreactors for enzyme-mediated catalysis.},

keywords = {Adsorption, openQCM NEXT, peptides, proteins, QCM-D, Quartz Crystal Microbalance, RAFT polymerization, Thickness, Vesicles},

pubstate = {published},

tppubtype = {article}

}

@article{javadzadehkalkhoran2024preparation,

title = {Preparation and Characterization of Affordable Experimental Setup for Particulate Matter Sensing},

author = {Majid Javadzadehkalkhoran and Levent Trabzon},

url = {https://link.springer.com/article/10.1007/s11220-024-00479-0},

doi = {https://doi.org/10.1007/s11220-024-00479-0},

year  = {2024},

date = {2024-05-20},

urldate = {2024-05-20},

journal = {Sensing and Imaging},

volume = {25},

number = {1},

pages = {29},

publisher = {Springer},

abstract = {The interest in particulate matter (PM) sensors has significantly increased over the last decade. It is crucial to have a proper experimental setup to test these sensors. However, most devices used in PM test setups, both for generating and measuring PM, are bulky and expensive. This study aims to solve this issue by designing a cost-effective experimental setup. The setup includes a custom-made PM generator, small-sized laser and quartz crystal microbalance (QCM) sensors. The PM generator can produce PM from three different sources: dry powder, liquid suspension, and combustion. The QCM is used to overcome the limitations of laser sensors for sensing ultra-fine particles. Moreover, the performance of the QCM sensor has been investigated with various PM sources and ambient conditions. The study reveals that the QCM response can be influenced by the PM source and ambient conditions. Changes in PM composition and size significantly impact the QCM response. Additionally, relative humidity (RH) can alter the sensor response by up to 22%. While the temperature change in the flow has an insignificant effect on the bare QCM response, increasing the temperature from 25 °C to 30 °C results in a 12% change in the QCM response for the grease-coated sensor. Notably, the QCM sensor demonstrates the best response with small-sized smoke PMs, with the least impact from ambient conditions. The laser sensors work very well with large particles; however, they struggle with small-sized smoke PMs.},

keywords = {air quality, openQCM Q-1, Particulate matter, PM, PM generator, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{KUNCAK2024115501,

title = {Automating data classification for label-free point-of-care biosensing in real complex samples},

author = {Jakub Kunčák and Michala Forinová and Alina Pilipenco and Viktor Procházka and Petr Horák and Sofya Dmitrievna Sycheva and Ivan Gennadievich Deyneka and Hana Vaisocherová-Lísalová},

url = {https://www.sciencedirect.com/science/article/pii/S0924424724004953},

doi = {https://doi.org/10.1016/j.sna.2024.115501},

issn = {0924-4247},

year  = {2024},

date = {2024-05-19},

urldate = {2024-01-01},

journal = {Sensors and Actuators A: Physical},

pages = {115501},

abstract = {Surface-based affinity biosensors present a promising avenue for point-of-care (POC) pathogen detection in real-world samples. While laboratory-based devices commonly employ various techniques to mitigate noise, signal drifts, fluidic artifacts, and other system imperfections, their simple cost-effective POC counterparts designed for field use frequently lack such capabilities. This paper addresses this gap by introducing a procedure for automatically classifying pathogen presence in unprocessed liquids from direct detection data measured by a simple POC quartz crystal microbalance sensor device. The procedure integrates classical analytical tools such as filtering, data selection, baseline de-drifting, and result calculation in tailored successive steps, considering the nature of the sensor signal and the challenges posed by real-world media. We show that the developed procedure exhibits exceptional robustness across different biosensing assays and complex real-world media. Through optimizing parameters using diverse datasets encompassing Escherichia coli O157:H7 (E. coli) and SARS-CoV-2 detection in various media including food-derived matrices and cell culture media, we achieved rates of successful detection as high as 80.8% and 90.9% for E. coli and SARS-CoV-2, respectively, without extensive machine learning. Furthermore, we analyse the sensitivity of the procedure to variations of input parameters and with examples discuss key factors influencing overall procedure accuracy. Our results suggest that this exceptionally robust method holds potential as a straightforward tool for automating sample classification in point-of-care diagnostics, underpinning its promising broader applicability.},

keywords = {. O157:H7, automatic data classification, Detection of pathogens, openQCM Q-1, Point-of-care biosensors, QCM-D, Quartz Crystal Microbalance, SARS-CoV-2},

pubstate = {published},

tppubtype = {article}

}

@article{buksa2024arginine,

title = {Arginine-Functional Methacrylic Block Copolymer Nanoparticles: Synthesis, Characterization, and Adsorption onto a Model Planar Substrate},

author = {Hubert Buksa and Edwin C Johnson and Derek HH Chan and Rory J McBride and George Sanderson and Rebecca M Corrigan and Steven P Armes},

url = {https://pubs.acs.org/doi/10.1021/acs.biomac.4c00128?goto=supporting-info},

doi = {https://pubs.acs.org/doi/10.1021/acs.biomac.4c00128?goto=supporting-info},

year  = {2024},

date = {2024-05-02},

urldate = {2024-05-02},

journal = {Biomacromolecules},

publisher = {ACS Publications},

abstract = {Recently, we reported the synthesis of a hydrophilic aldehyde-functional methacrylic polymer (Angew. Chem., 2021, 60, 12032–12037). Herein we demonstrate that such polymers can be reacted with arginine in aqueous solution to produce arginine-functional methacrylic polymers without recourse to protecting group chemistry. Careful control of the solution pH is essential to ensure regioselective imine bond formation; subsequent reductive amination leads to a hydrolytically stable amide linkage. This new protocol was used to prepare a series of arginine-functionalized diblock copolymer nanoparticles of varying size via polymerization-induced self-assembly in aqueous media. Adsorption of these cationic nanoparticles onto silica was monitored using a quartz crystal microbalance. Strong electrostatic adsorption occurred at pH 7 (Γ = 14.7 mg m–2), whereas much weaker adsorption occurred at pH 3 (Γ = 1.9 mg m–2). These findings were corroborated by electron microscopy, which indicated a surface coverage of 42% at pH 7 but only 5% at pH 3},

keywords = {aldehyde-functional, nanoparticles, openQCM NEXT, polymers, QCM, QCM-D, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{al2024development,

title = {Development of Poly (safranine-co-phenosafranine)/GNPs/MWCNTs Nanocomposites for Quartz Crystal Microbalance Sensor Detection of Arsenic (III) Ions},

author = {Salsabeel Al-Sodies and Abdullah M Asiri and Sameh Ismail and Khalid A Alamry and Mahmoud Hussein Abdo},

url = {https://iopscience.iop.org/article/10.1088/2053-1591/ad37a5/meta},

year  = {2024},

date = {2024-04-12},

urldate = {2024-04-12},

journal = {Materials Research Express},

abstract = {Contamination of drinking water by heavy metals is extremely dangerous to human health. The formation of a quartz crystal microbalance (QCM) sensor for the rapid and portable detection of harmful heavy metals such as arsenic (As) ions in water samples is detailed in this work. Equimolar ratios of safranine (SF) and phenosafranine (Ph) copolymers (PSF-Ph) were synthesized via a chemical oxidative polymerization approach. The copolymer was modified with multi-wall carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs) at different percentages (1, 3, 5, and 10%) to form nanocomposites of PSF-Ph/MWCNTs/GNPs. Thermal analysis of the nanocomposites revealed that the final polymer decomposition temperature (PDTfinal) values fell between 619 and 630 °C, and the nanocomposite with 10% loading exhibited the highest decomposition temperatures for T10, T30, and T50. The nanohybrid QCM sensor detected As(III) down to parts-per-billion levels based on the change in the oscillation frequency. The sensor was tested on water samples spiked with different concentrations of As(III) (0–20 ppb). A strong linear correlation (R2 ≈ 0.99) between the frequency shift and concentration with a low detection limit (0.1 ppb) validated the quantitative detection capability of the sensor. This QCM platform with an optimal recognition ligand is a promising field-deployable tool for on-site arsenic analysis in water.},

keywords = {contamination, Drinking water, GNPs (Graphene Nanoplatelets), MWCNTs (Multi-Walled Carbon Nanotubes), Nanocomposites, openQCM sensors, Poly(phenosafranine), Poly(safranine), QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{haldar2024steering,

title = {Steering diffusion selectivity of chemical isomers within aligned nanochannels of metal-organic framework thin film},

author = {Ritesh Haldar and Tanmoy Maity and Susmita Sarkar and Susmita Kundu and Suvendu Panda and Arighna Sarkar and Kalyaneswar Mandal and Soumya Ghosh and Jagannath Mondal},

url = {https://www.researchsquare.com/article/rs-4046811/v1},

doi = {https://doi.org/10.21203/rs.3.rs-4046811/v1},

year  = {2024},

date = {2024-03-21},

urldate = {2024-03-21},

abstract = {The movement of molecules (i.e. diffusion) within angstrom-scale pores of porous materials such as metal-organic frameworks (MOFs) and zeolites is influenced by multiple complex factors that can be challenging to assess and manipulate. Nevertheless, understanding and controlling this diffusion phenomenon is crucial for advancing energy-economic membrane-based chemical separation technologies, as well as for heterogeneous catalysis and sensing applications. Through precise assessment of the factors influencing diffusion within a porous metal-organic framework (MOF) thin film, we have developed a chemical strategy to manipulate and reverse chemical isomer diffusion selectivity. In the process of cognizing the molecular diffusion within oriented, angstrom-scale channels of MOF thin film, we have unveiled a dynamic chemical interaction between the adsorbate (chemical isomers) and the MOF using a combination of kinetic mass uptake experiments and molecular simulation. Leveraging the dynamic chemical interactions, we have reversed the haloalkane (positional) isomer diffusion selectivity, forging a novel chemical pathway to elevate the overall efficacy of membrane-based chemical separation and selective catalytic reactions.},

keywords = {Metal organic frameworks, MOFs, molecular diffusion, nanoporous materials, openQCM sensors, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{kunvcak2024automating,

title = {Automating Data Analysis for Point-of-Care Label-Free Surface-Based Affinity Biosensors Dealing with Complex Biological Samples: Escherichia Coli O157: H7 and Sars-Cov-2 Case Studies},

author = {Jakub Kunčák and Michala Forinová and Alina Pilipenco and Viktor Procházka and Petr Horák and Sycheva Sofya Dmitrievna and Ivan Gennadievich Deyneka and Hana Vaisocherová-L'isalová},

url = {https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4756321},

year  = {2024},

date = {2024-03-20},

urldate = {2024-03-20},

journal = {Available at SSRN 4756321},

abstract = {Surface-based affinity biosensors offer a promising avenue for point-of-care (POC) detection of pathogens in real-world samples. While laboratory-based devices commonly employ various techniques to compensate for noise, signal drifts, fluidic artifacts, and other system imperfections, their POC counterparts aiming at providing simple cost-effective detection platforms for field use, often lack these qualities. This paper addresses this gap by introducing a procedure for automatic classification of pathogen presence in unprocessed liquids from direct detection data measured by a simple POC-relevant quartz crystal microbalance sensor device.  By considering the nature of the sensor signal and the sources of its imperfections in real-world media, a straightforward procedure integrates “classical” analytical tools (filtering, data selection, baseline de-drifting, and result calculation) in successive steps to automate sample classification without the need for extensive machine learning. Through optimizing parameters using diverse datasets encompassing Escherichia coli O157:H7 (E. coli) and SARS-CoV-2 detection in various media including food-derived matrices and cell culture media, we achieved rates of successful detection as high as 80.8% and 90.9% for E. coli and SARS-CoV-2, respectively. Furthermore, we analyse the sensitivity of the routine to variations of input parameters and with examples discuss the key factors influencing the accuracy of the overall procedure. The results show that the developed method exhibits exceptional robustness across different biosensing assays and complex real-world media, highlighting its promising broader applicability in point-of-care diagnostics.},

keywords = {automatic data classification, Detection of pathogens, E. coli O157:H7, openQCM, openQCM Q-1, Point-of-care biosensors, Quartz Crystal Microbalance, SARS-CoV-2},

pubstate = {published},

tppubtype = {article}

}

@article{skladal2024piezoelectric,

title = {Piezoelectric biosensors: shedding light on principles and applications},

author = {Petr Skládal},

url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10920441/},

doi = {https://doi.org/10.1007%2Fs00604-024-06257-9},

year  = {2024},

date = {2024-03-07},

urldate = {2024-03-07},

journal = {Microchimica Acta},

volume = {191},

number = {4},

pages = {184},

publisher = {Springer},

abstract = {The three decades of experience with piezoelectric devices applied in the field of bioanalytical chemistry are shared. After introduction to principles and suitable measuring approaches, active and passive methods based on oscillators and impedance analysis, respectively, the focus is directed towards biosensing approaches. Immunosensing examples are provided, followed by other affinity sensing approaches based on hybridization of nucleic acids, aptamers, monitoring of enzyme activities, and detection of pathogenic microbes. The combination of piezosensors with cell lines and testing of drugs is highlighted, including mechanically active cells. The combination of piezosensors with other measuring techniques providing original hybrid devices is briefly discussed.},

keywords = {Cellular biosensors, Combined biosensing set-ups, Enzyme activity, Immunosensors, Microbial detection, openQCM, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{millan2023degradation,

title = {Degradation kinetics of medium chain length Polyhydroxyalkanoate degrading enzyme: a quartz crystal microbalance study},

author = {Fabien Millan and Nils Hanik},

url = {https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2023.1303267/full},

doi = {https://doi.org/10.3389/fbioe.2023.1303267},

year  = {2023},

date = {2023-12-14},

urldate = {2023-12-14},

journal = {Frontiers in Bioengineering and Biotechnology},

volume = {11},

pages = {1303267},

publisher = {Frontiers Media SA},

abstract = {This study investigates the enzymatic degradation processes of different classes of polyhydroxyalkanoates (PHAs), a group of biopolymers naturally synthesized by various microorganisms. Medium chain length PHAs (mcl-PHAs) are distinguished biopolymers due to their biodegradability and diverse material properties. Using quartz crystal microbalance measurements as a valuable tool for accurate real-time monitoring of the enzymatic degradation process, the research provides detailed kinetic data, describing the interaction between enzymes and substrates during the enzymatic degradation process. Thin films of poly-3-hydroxybutyrate (PHB) and polyhydroxyoctanoate copolymer (PHO), containing molar fractions of about 84% 3-hydroxyoctanoate and 16% 3-hydroxyhexanoate, were exposed to scl-depolymerases from Pseudomonas lemoignei LMG 2207 and recombinant mcl-depolymerase produced in Escherichia coli DH5α harboring the plasmid pMAD8, respectively. Analyses based on a heterogeneous kinetic model for the polymer degradation indicated a six-fold stronger adsorption equilibrium constant of mcl-depolymerase to PHO. Conversely, the degradation rate constant was approximately twice as high for scl-depolymerases acting on PHB. Finally, the study highlights the differences in enzyme-substrate interactions and degradation mechanisms between the investigated scl- and mcl-PHAs.},

keywords = {biodegradable polymers, degradation kinetics, depolymerase enzymes, enzymatic degradation, openQCM, openQCM Q-1, polyhydroxyalkanoates, Python, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{forinova2023comparative,

title = {A Comparative Assessment of a Piezoelectric Biosensor Based on a New Antifouling Nanolayer and Cultivation Methods: Enhancing S. aureus Detection in Fresh Dairy Products},

author = {Michala Forinová and Anna Seidlová and Alina Pilipenco and N Scott Lynn Jr and Radka Obořilová and Zdeněk Farka and Petr Skládal and Alena Saláková and Monika Spasovová and Milan Houska and others},

url = {https://www.sciencedirect.com/science/article/pii/S2590262823000485},

doi = {https://doi.org/10.1016/j.crbiot.2023.100166},

year  = {2023},

date = {2023-11-23},

urldate = {2023-11-23},

journal = {Current Research in Biotechnology},

pages = {100166},

publisher = {Elsevier},

abstract = {Ensuring dairy product safety demands rapid and precise Staphylococcus aureus (S. aureus) detection. Biosensors show promise, but their performance is often demonstrated in model samples using non-native pathogens and has never been studied towards S. aureus detection in naturally contaminated samples. This study addresses the gap by directly comparing results taken with a novel piezoelectric biosensor, capable of one-step detection, with four conventional cultivation-based methods. Our findings reveal that this biosensor, based on an antifouling nanolayer-coated biochip, exhibits exceptional resistance to biofouling from unprocessed dairy products and is further capable of specific S. aureus detection. Notably, it performed comparably to Petrifilm and Baird-Parker methods but delivered results in only 30 min, bringing a substantial reduction from the 24 h required by cultivation-based techniques. Our study also highlights differences in the performance of cultivation methods when analyzing artificially spiked versus naturally contaminated foods. These findings underline the potential of antifouling biosensors as efficient reliable tools for rapid, cost-effective, point-of-care testing, enhancing fresh dairy product safety and S. aureus detection.},

keywords = {Antifouling coating, biosensors, Cultivation-based methods, openQCM Q-1, QCM-D, Quartz Crystal Microbalance, S. aureus},

pubstate = {published},

tppubtype = {article}

}

@article{khoirudin2023influence,

title = {Influence of the SMN antibody on quartz crystal microbalance with dissipation (QCM-D) surface as an SMN protein biosensor},

author = {Hanif Khoirudin and Rizky Aflaha and Eldiana Rully Arsetiyani and Ari Dwi Nugraheni and Dian Kesumapramudya Nurputra and Kuwat Triyana and Ahmad Kusumaatmaja},

year  = {2023},

date = {2023-11-06},

urldate = {2023-01-01},

journal = {MRS Communications},

pages = {1--7},

publisher = {Springer},

abstract = {The lack of survival motor neuron (SMN) protein levels can lead to spinal muscular atrophy (SMA) disease. In this study, an SMN protein biosensor based on quartz crystal microbalance with dissipation (QCM-D) was developed. The sensor was coated with polyvinyl alcohol (PVA) nanofiber and doped with SMN antibodies to increase the sensitivity. Scanning electron microscope (SEM) images showed that the nanofiber was undamaged after doping the SMN antibody. The sensitivity of the QCM-D sensor was 21.2 Hz/% after doping SMN antibodies and had good stability for 3 days. Moreover, the sensor has been validated using western blot. Thus, the fabricated QCM-D-based biosensor has excellent potential in detecting SMN levels in human blood plasma.},

key = {QCM-D, openQCM, Quartz Crystal Microbalance, neuron, protein, antibodies, nanofiber, SEM},

keywords = {antibody detection, Nanofiber, Nanofibers, neuron, openQCM, protein, QCM-D, Quartz Crystal Microbalance, SEM},

pubstate = {published},

tppubtype = {article}

}

@article{muff2023preparation,

title = {Preparation of Well-Defined Fluorescent Nanoplastic Particles by Confined Impinging Jet Mixing},

author = {Livius F Muff and Sandor Balog and Jozef Adamcik and Christoph Weder and Roman Lehner},

url = {https://link.springer.com/article/10.1557/s43579-023-00492-6},

doi = {https://doi.org/10.1557/s43579-023-00492-6},

year  = {2023},

date = {2023-11-01},

urldate = {2023-11-01},

journal = {Environmental Science & Technology},

publisher = {ACS Publications},

abstract = {Research on the origin, distribution, detection, identification, and quantification of polymer nanoparticles (NPs) in the environment and their possible impact on animal and human health is surging. For different types of studies in this field, well-defined reference materials or mimics are needed. While isolated reports on the preparation of such materials are available, a simple and broadly applicable method that allows for the production of different NP types with well-defined, tailorable characteristics is still missing. Here, we demonstrate that a confined impinging jet mixing process can be used to prepare colloidally stable NPs based on polystyrene, polyethylene, polypropylene, and poly(ethylene terephthalate) with diameters below < 100 nm. Different fluorophores were incorporated into the NPs, to allow their detection in complex environments. To demonstrate their utility and detectability, fluorescent NPs were exposed to J774A.1 macrophages and visualized using laser scanning microscopy. Furthermore, we modified the NPs in a postfabrication process and changed their shape from spherical to heterogeneous geometries, in order to mimic environmentally relevant morphologies. The methodology used here should be readily applicable to other polymers and payloads and thus a broad range of NPs that enable studies of their behavior, uptake, translocation, and biological end points in different systems.},

key = {QC; openQCM, Quartz Crystal Microbalance},

keywords = {confined impinging jet (CIJ) mixer, flash nanoprecipitation, fluorescent label, fluorophore, nanoemulsion, nanoplastic, openQCM, polymer nanoparticles, QCM, Quartz Crystal Microbalance, shape modification},

pubstate = {published},

tppubtype = {article}

}

@article{milsom2023situ,

title = {In-situ measurements and modelling of the oxidation kinetics in films of a cooking aerosol proxy using a Quartz Crystal Microbalance with Dissipation monitoring (QCM-D)},

author = {Adam Milsom and Shaojun Qi and Ashmi Mishra and Thomas Berkemeier and Zhenyu Zhang and Christian Pfrang},

url = {https://acp.copernicus.org/articles/23/10835/2023/},

doi = {https://doi.org/10.5194/acp-23-10835-2023},

year  = {2023},

date = {2023-10-04},

urldate = {2023-10-04},

journal = {EGUsphere},

volume = {23},

issue = {19},

pages = {10835–10843},

publisher = {Copernicus Publications Göttingen, Germany},

abstract = {Aerosols and films are found in indoor and outdoor environments. How they interact with pollutants, such as ozone, has a direct impact on our environment via cloud droplet formation and the chemical persistence of toxic aerosol constituents. The chemical reactivity of aerosol emissions is typically measured spectroscopically or by techniques such as mass spectrometry, directly monitoring the amount of material during a chemical reaction. We present a study which indirectly measures oxidation kinetics in a common cooking aerosol proxy using a low-cost quartz crystal microbalance with dissipation monitoring (QCM-D). We validated this approach by comparison with kinetics measured both spectroscopically and with high-intensity synchrotron radiation. Using microscopy, we found that the film morphology changed and film rigidity increased during oxidation. There was evidence of surface crust formation on oxidised particles, though this was not consistent for all experiments. Crucially, our kinetic modelling of these experimental data confirmed that the oleic acid decay rate is in line with previous literature determinations, which demonstrates that performing such experiments on a QCM-D does not alter the underlying mechanism. There is clear potential to take this robust and low-cost but sensitive method to the field for in situ monitoring of reactions outdoors and indoors.},

keywords = {aerosol, Dissipation Monitoring, films, openQCM NEXT, Ozone, pollutants, pollution, QCM, QCM-D, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{aflaha2023maltodextrin,

title = {Maltodextrin-overlaid polyvinyl acetate nanofibers for highly sensitive and selective room-temperature ammonia sensors},

author = {Rizky Aflaha and Nur Laili Indah Sari and Laila Katriani and Ahmad Hasan As' ari and Ahmad Kusumaatmaja and Aditya Rianjanu and Roto Roto and Hutomo Suryo Wasisto and Kuwat Triyana},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0026265X23008561},

doi = {https://doi.org/10.1016/j.microc.2023.109237},

year  = {2023},

date = {2023-10-01},

urldate = {2023-10-01},

journal = {Microchemical Journal},

pages = {109237},

publisher = {Elsevier},

abstract = {Various ammonia sensors based on different materials have continuously been developed and employed to enable real-time monitoring of ammonia gas in the environment. Efforts are put not only to improve their sensitivity and selectivity towards the target gas but also to operate them at room temperature. Here, we investigated the effect of overlaying maltodextrin with different concentrations on the surface of polyvinyl acetate (PVAc) nanofibers on ammonia sensing performances, in which quartz crystal microbalance (QCM) was utilized as a transducer to measure the resonance frequency shift affected by the adsorbed gas molecules. Higher concentrations of the overlaying maltodextrin led to larger nanofiber diameter and more functional active groups on the active nanofibrous layers. PVAc nanofibers with 0.05% maltodextrin overlay demonstrated the highest sensitivity of 0.525 Hz·ppm−1 at room temperature, which was 6.4 times higher than their bare counterpart (nanofiber without maltodextrin overlay). That sensor also possessed fast response and recovery times of 32 s and 17 s with a low detection limit (1.92 ppm). Besides its high reproducibility, reversibility, and repeatability, the sensor exhibited outstanding selectivity to other gas analytes and good long-term stability for 32 days of testing. This research shows that maltodextrin overlay can be used as a low-cost alternative route to increase the performance of organic material-based ammonia sensors, especially polymer nanofibers.},

key = {QCM, 10 MHz, QCM sensors, polyvinyl acetate, nanofibers, ammonia},

keywords = {10 MHz, Ammonia, Nanofibers, openQCM sensors, Polyvinyl acetate, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{JANG2023134589,

title = {Heated quartz crystal microbalance with highly controlled integration of ZIF-67 for ultra-reliable humidity sensing},

author = {Il Ryu Jang and Sugato Hajra and Rojalin Sahu and Hoe Joon Kim},

url = {https://www.sciencedirect.com/science/article/pii/S0925400523013047},

doi = {https://doi.org/10.1016/j.snb.2023.134589},

issn = {0925-4005},

year  = {2023},

date = {2023-09-09},

urldate = {2023-01-01},

journal = {Sensors and Actuators B: Chemical},

pages = {134589},

abstract = {The quartz crystal microbalance (QCM) is widely utilized in various fields for detecting parameters such as relative humidity (RH). However, the reliability of QCM as an RH sensor can be compromised by the nonuniform integration of sensing materials and the absence of a dehumidification system for calibration. Damping of the sensor performance may occur due to excessive water molecule adsorption on agglomerated sensing materials, while ineffective desorption of water molecules from these materials renders QCM-based humidity sensors unreliable in highly humid environments. This study presents an innovative approach to achieve area-specific and highly-controlled integration of ZIF-67 on a quartz crystal microbalance (QCM) using electrospray deposition (ESD). The proposed method effectively decorates the sensor surface with exceptional picogram (pg) mass resolution. Additionally, an integrated microheater facilitates rapid sensor heating, eliminating residual water molecules and enhancing the proposed self-recalibration method. The comparative analysis demonstrates that the heated sensor exhibits a remarkable improvement of 47 times in hysteresis and 8 times in drift performance compared to the non-heated sensor. These findings hold great promise for enhancing the reliability of QCM-based humidity sensors, thereby finding utility in diverse research and application fields.},

keywords = {10 MHz, metal-organic framework, microheater, openQCM sensors, Quartz Crystal Microbalance, sensor calibration, ZIF-67},

pubstate = {published},

tppubtype = {article}

}

@article{aflaha2023enhanced,

title = {Enhanced trimethylamine gas sensor sensitivity based on quartz crystal microbalance using nanofibers overlaid with maltodextrin},

author = {Rizky Aflaha and Laila Katriani and Ahmad Hasan As’ ari and Nur Laili Indah Sari and Ahmad Kusumaatmaja and Aditya Rianjanu and Roto Roto and Kuwat Triyana},

url = {https://link.springer.com/article/10.1557/s43579-023-00409-3},

doi = {https://doi.org/10.1557/s43579-023-00409-3},

year  = {2023},

date = {2023-08-03},

urldate = {2023-08-03},

journal = {MRS Communications},

pages = {1--9},

publisher = {Springer},

abstract = {This study proposes a novel quartz crystal microbalance-based sensor using polyvinyl acetate nanofibers overlaid with maltodextrin to enhance sensitivity toward trimethylamine (TMA) gas. The sensor demonstrated a remarkable increase in sensitivity by 8.3 times, with a detection limit of 15.6 ppm. The enhanced sensitivity is due to reversible intermolecular Lewis acid–base interaction between active groups of maltodextrin and TMA gas molecules. Moreover, the sensor exhibited good selectivity, stability, and fast response and recovery times of 141 s and 116 s, respectively. The proposed sensor offers a promising alternative to conventional methods for accurately monitoring TMA gas levels in the air.},

key = {openqCM, QCM , quartz Crystal Microbalance openQCM sensors},

keywords = {openQCM, openQCM sensors, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{hunter2023mucoadhesive,

title = {Mucoadhesive Pickering Nanoemulsions via Dynamic Covalent Chemistry},

author = {Saul J Hunter and Mahmoud H Abu Elella and Edwin C Johnson and Laura Taramova and Emma E Brotherton and Steven P Armes and Vitaliy V Khutoryanskiy and Mark J Smallridge},

url = {https://www.sciencedirect.com/science/article/pii/S0021979723014200},

doi = {https://doi.org/10.1016/j.jcis.2023.07.162},

year  = {2023},

date = {2023-07-27},

urldate = {2023-07-27},

journal = {Journal of Colloid and Interface Science},

publisher = {Elsevier},

abstract = {Hypothesis. Submicron oil droplets stabilized using aldehyde-functionalized nanoparticles should adhere to the primary amine groups present at the surface of sheep nasal mucosal tissue via Schiff base chemistry. Experiments. Well-defined sterically-stabilized diblock copolymer nanoparticles of 20 nm diameter were prepared in the form of concentrated aqueous dispersions via reversible addition-fragmentation chain transfer (RAFT) aqueous emulsion polymerization of 2,2,2-trifluoroethyl methacrylate (TFEMA) using a water-soluble methacrylic precursor bearing cis-diol groups. Some of these hydroxyl-functional nanoparticles were then selectively oxidized using an aqueous solution of sodium periodate to form a second batch of nanoparticles bearing pendent aldehyde groups within the steric stabilizer chains. Subjecting either hydroxyl- or aldehyde-functional nanoparticles to high-shear homogenization with a model oil (squalane) produced oil-in-water Pickering macroemulsions of 20-30 µm diameter. High-pressure microfluidization of such macroemulsions led to formation of the corresponding Pickering nanoemulsions with a mean droplet diameter of around 200 nm. Quartz crystal microbalance (QCM) experiments were used to examine adsorption of both nanoparticles and oil droplets onto a model planar substrate bearing primary amine groups, while a fluorescence microscopy-based mucoadhesion assay was developed to assess adsorption of the oil droplets onto sheep nasal mucosal tissue. Findings. Squalane droplets coated with aldehyde-functional nanoparticles adhered significantly more strongly to sheep nasal mucosal tissue than those coated with the corresponding hydroxyl-functional nanoparticles. This difference was attributed to the formation of surface imine bonds via Schiff base chemistry and was also observed for the two types of nanoparticles alone in QCM studies. Preliminary biocompatibility studies using planaria indicated only mild toxicity for these new mucoadhesive Pickering nanoemulsions, suggesting potential applications for the localized delivery of hydrophobic drugs.},

keywords = {Aldehyde-Functionalized Nanoparticles, Mucoadhesive Drug, Nanoemulsions, openQCM NEXT, QCM-D, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{Sukowati_Rohman_Agung_Hapidin_Damayanti_Khairurrijal_2023,

title = {An investigation of the influence of nanofibers morphology on the performance of QCM-based ethanol vapor sensor utilizing polyvinylpyrrolidone nanofibers active layer},

author = {Riris Sukowati and Yadi Mulyadi Rohman and Bertolomeus Haryanto Agung and Dian Ahmad Hapidin and Herlina Damayanti and Khairurrijal Khairurrijal},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0925400523004239},

doi = {10.1016/j.snb.2023.133708},

year  = {2023},

date = {2023-07-01},

urldate = {2023-07-01},

journal = {Sensors and Actuators B: Chemical},

volume = {386},

pages = {133708},

abstract = {Quartz crystal microbalances (QCMs) coated by polyvinylpyrrolidone (PVP) nanofibers with controlled morphology have been made for ethanol vapor detection. We used electrospinning to deposit PVP nanofibers of different morphologies (spherical-beaded, spindle-beaded, and pure nanofiber) on a QCM surface to study the effect on sensor performance. BET characterization revealed that the spherical-beaded nanofiber had the highest BET-specific surface area than the other morphologies, which improves the QCM sensor sensitivity, limit of quantification (LOQ), limit of detection (LOD), and sensor response. QCM coated with spherical-beaded nanofiber showed improved sensitivity of 2.632 Hz/ppm, lower LOD and LOQ of 0.018 ppm and 0.061 ppm, and better response compared to those coated with spindle-beaded and pure nanofiber. Based on adsorption isotherm models, Freundlich adsorption isotherm was found to be the most suitable for describing ethanol vapor adsorption on the sensor. The high sensitivity of the sensor to ethanol vapor was attributed to hydrogen bonding interactions between the sensor and the ethanol molecules. This study shows that the QCM-based sensor performance can be improved by modifying the morphology of nanofibrous coating layer.},

key = {QCM, Quartz Crystal Microbalance, openQCM Wi2, polyvinylpyrrolidone, nanofibers, ethanol vapor},

keywords = {ethanol vapor, Nanofibers, openQCM Wi2, polyvinylpyrrolidone, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{ermek2023electrospun,

title = {Electrospun biotin-and streptavidin-coated quartz crystal microbalance surfaces: characterization and mass sensing performance using OpenQCM},

author = {Erhan Ermek and Esra Ayan and Nurettin Tokay and Hasan DeMirci and Abdullah Kepceoğlu},

url = {https://www.researchsquare.com/article/rs-2995721/v1},

doi = {https://doi.org/10.21203/rs.3.rs-2995721/v1},

year  = {2023},

date = {2023-06-06},

urldate = {2023-06-06},

abstract = {In this study, a quartz crystal microbalance (QCM) sensor surface was coated with biotin and/or streptavidin using the electrospinning method. The coated surfaces were analyzed using the Raman spectroscopy method. QCM measurements were carried out using the OpenQCM platform. The results indicate that the electrospinning method can be used to coat QCM surfaces with biotin and/or streptavidin and that the coated surfaces exhibit distinct morphological and spectroscopic properties. The QCM measurements showed that the coated surfaces are highly sensitive to changes in mass, indicating their potential for use in biosensing applications. Overall, this study provides new insights into the use of QCM sensors coated with biotin and/or streptavidin for biological sensing and detection applications.},

keywords = {Biosensing, Biotin, Electrospinning, openQCM, QCM, Quartz Crystal Microbalance, Raman spectroscopy, Streptavidin, Surface coating},

pubstate = {published},

tppubtype = {article}

}

@article{malhotra2023room,

title = {Room-temperature monitoring of CH4 and CO2 using a metal-organic framework-based QCM sensor showing inherent analyte discrimination},

author = {Jaskaran Singh Malhotra and Mariusz Kubus and Kasper Steen Pedersen and Simon Ivar Andersen and Jonas Sundberg},

url = {https://chemrxiv.org/engage/chemrxiv/article-details/646b938eccabde9f6e2fd280},

doi = {https://doi.org/10.26434/chemrxiv-2023-djhp2},

year  = {2023},

date = {2023-05-24},

urldate = {2023-05-24},

abstract = {The detection of methane and carbon dioxide is of growing importance due to their negative impact on global warming. This is true both for environmental monitoring, as well as leak detection in industrial processes. Although solid-state sensors are technologically mature, they have limitations that prohibit their use in certain situations, e.g., explosive atmospheres. Thus, there is a need to develop new types of sensor materials. Herein, we demonstrate a simple, low-cost metal-organic framework-based gas leak detection sensor. The system is based on gravimetric sensing using a quartz crystal microbalance. The quartz crystal is functionalized by layer-by-layer growth of a thin metal-organic framework film. This film shows selective uptake of methane or carbon dioxide under atmospheric conditions. The hardware has low cost, simple operation, and theoretically high sensitivity. Overall, the sensor is characterized by simplicity and high robustness. Furthermore, by exploiting the different adsorption kinetics as measured by multiple harmonics analyses, it is possible to discriminate whether the response is due to methane or carbon dioxide. In summary, we demonstrate data relevant towards new applications of metal-organic frameworks and microporous hybrid materials in sensing applications.},

keywords = {carbon dioxide, CH4, CO2, Dissipation, metal-organic frameworks, methane, openQCM NEXT, QCM, QCM-D, Quartz Crystal Microbalance, sensors},

pubstate = {published},

tppubtype = {article}

}

@article{lino2023development,

title = {Development of a QCM-based biosensor for the detection of non-small cell lung cancer biomarkers in liquid biopsies},

author = {Catarina Lino and Sara Barrias and Raquel Chaves and Filomena Adega and José Ramiro Fernandes and Paula Martins-Lopes},

url = {https://www.sciencedirect.com/science/article/pii/S0039914023003752},

doi = {https://doi.org/10.1016/j.talanta.2023.124624},

year  = {2023},

date = {2023-05-04},

urldate = {2023-05-04},

journal = {Talanta},

pages = {124624},

publisher = {Elsevier},

abstract = {Lung cancer is the main malignant cancer reported worldwide, with one of the lowest survival rates. Deletions in the Epidermal Growth Factor Receptor (EGFR) gene are often associated with non-small cell lung cancer (NSCLC), a common subtype of lung cancer. The detection of such mutations provides key information for the diagnosis and treatment of the disease; therefore, the early screening of such biomarkers is of vital importance. The need for fast, reliable, and early detection means applied to NSCLC has led to the development of highly sensitive devices that can detect cancer-associated mutations. Such devices, known as biosensors, are a promising alternative to more conventional detection methods and can potentially alter the way cancer is diagnosed and treated. In this study, we report the development of a DNA-based biosensor, namely a quartz crystal microbalance (QCM), applied to the detection of NSCLC, from liquid biopsies samples. The detection, as is the case of most DNA biosensors, is based on the hybridization between the NSCLC-specific probe and the sample DNA (containing specific mutations associated with NSCLC). The surface functionalization was performed with a blocking agent (dithiothreitol) and thiolated-ssDNA strands. The biosensor was able to detect specific DNA sequences in both synthetic and real samples. Aspects such as reutilization and regeneration of the QCM electrode were also studied.},

key = {QCM, Quartz Crystal Microbalance, openQCM Q-1, DNA, cancer, biosensor, blood plasma},

keywords = {biosensors, blood plasma, Cancer, DNA, openQCM Q-1, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{lim2023quartz,

title = {Quartz crystal microbalance-based biosensing of proteins using molecularly imprinted polydopamine sensing films: Interplay between protein characteristics and molecular imprinting effect},

author = {Hui Jean Lim and Tridib Saha and Beng Ti Tey and Sunil Kumar Lal and Chien Wei Ooi},

url = {https://www.sciencedirect.com/science/article/abs/pii/S2468023023002742},

doi = {https://doi.org/10.1016/j.surfin.2023.102904},

year  = {2023},

date = {2023-04-29},

urldate = {2023-04-29},

journal = {Surfaces and Interfaces},

pages = {102904},

publisher = {Elsevier},

abstract = {Biomimetic sensing films based on molecularly imprinted polydopamine (MIPDA) offer a simple, biocompatible, and versatile approach to functionalise quartz crystal microbalance (QCM)-based biosensors for the recognition of target proteins. This study aims to investigate the chemical, morphological, and recognition properties of MIPDA sensing films polymerised on the QCM crystal surface and elucidate the impacts of various parameters on the liquid-phase biosensing behaviour. Pepsin, bovine serum albumin, human serum albumin, and lysozyme were used as model proteins to study the effect of molecular imprinting and the influence of protein characteristics on the recognition behaviour of MIPDA-functionalised QCM crystals. Analysis of the protein adsorption patterns revealed that the MIPDA film contained heterogeneous binding sites with a dissociation constant in the µM range, showing that the binding affinity of the synthetic sensing film for the target protein was comparable to that of commonly used bioreceptors. In a case study using a pepsin-imprinted MIPDA film, the specific conformation and surface chemistry of the recognition cavities were discovered to promote the binding of pepsin (imprinting factor = 5.78) while simultaneously reducing the nonspecific binding of incompatible proteins on the QCM crystal surface. Protein recognition on MIPDA-functionalised QCM crystals was found to be governed by a combination of nonspecific interactions (e.g., electrostatic and polar interactions) between the proteins and the MIPDA sensing film. The findings indicate that increasing the density of selective recognition cavities in the MIPDA film and optimising the sample pH are key strategies to improve the selectivity and sensitivity for protein biosensing.},

keywords = {molecularly imprinting, openQCM Q-1, polydopamine, proteins, QCM, Quartz Crystal Microbalance, sensing films},

pubstate = {published},

tppubtype = {article}

}

@article{maity2023chemically,

title = {Chemically routed interpore molecular diffusion in metal-organic framework thin films},

author = {Tanmoy Maity and Pratibha Malik and Sumit Bawari and Soumya Ghosh and Jagannath Mondal and Ritesh Haldar},

url = {https://pubmed.ncbi.nlm.nih.gov/37072404/},

doi = {https://doi.org/10.1038/s41467-023-37739-8},

year  = {2023},

date = {2023-04-18},

urldate = {2023-04-18},

journal = {Nature Communications},

volume = {14},

number = {1},

pages = {2212},

publisher = {Nature Publishing Group UK London},

abstract = {Transport diffusivity of molecules in a porous solid is constricted by the rate at which molecules move from one pore to the other, along the concentration gradient, i.e. by following Fickian diffusion. In heterogeneous porous materials, i.e. in the presence of pores of different sizes and chemical environments, diffusion rate and directionality remain tricky to estimate and adjust. In such a porous system, we have realized that molecular diffusion direction can be orthogonal to the concentration gradient. To experimentally determine this complex diffusion rate dependency and get insight of the microscopic diffusion pathway, we have designed a model nanoporous structure, metal-organic framework (MOF). In this model two chemically and geometrically distinct pore windows are spatially oriented by an epitaxial, layer-by-layer growth method. The specific design of the nanoporous channels and quantitative mass uptake rate measurements have indicated that the mass uptake is governed by the interpore diffusion along the direction orthogonal to the concentration gradient. This revelation allows chemically carving the nanopores, and accelerating the interpore diffusion and kinetic diffusion selectivity.},

keywords = {molecular diffusion, Nanoporous channels, openQCM NEXT, QCM, QCM-D, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{rohman2023quartz,

title = {Quartz Crystal Microbalance Coated with Polyacrylonitrile/Nickel Nanofibers for High-Performance Methanol Gas Detection},

author = {Yadi Mulyadi Rohman and Riris Sukowati and Aan Priyanto and Dian Ahmad Hapidin and Dhewa Edikresnha and Khairurrijal Khairurrijal},

url = {https://pubs.acs.org/doi/full/10.1021/acsomega.3c00760},

doi = {https://doi.org/10.1021/acsomega.3c00760},

year  = {2023},

date = {2023-03-29},

urldate = {2023-01-01},

journal = {ACS Omega},

publisher = {ACS Publications},

abstract = {This study describes a sensor based on quartz crystal microbalance (QCM) coated by polyacrylonitrile (PAN) nanofibers containing nickel nanoparticles for methanol gas detection. The PAN/nickel nanofibers composites were made via electrospinning and electrospray methods. The QCM sensors coated with the PAN/nickel nanofiber composite were evaluated for their sensitivities, selectivities, and stabilities. The morphologies and elemental compositions of the sensors were examined using a scanning electron microscope-energy dispersive X-ray. A Fourier Transform Infrared spectrometer was used to investigate the elemental bonds within the nanofiber composites. The QCM sensors coated with PAN/nickel nanofibers offered a high specific surface area to enhance the QCM sensing performance. They exhibited excellent sensing characteristics, including a high sensitivity of 389.8 ± 3.8 Hz/SCCM, response and recovery times of 288 and 251 s, respectively, high selectivity for methanol compared to other gases, a limit of detection (LOD) of about 1.347 SCCM, and good long-term stability. The mechanism of methanol gas adsorption by the PAN/nickel nanofibers can be attributed to intermolecular interactions, such as the Lewis acid–base reaction by PAN nanofibers and hydrogen bonding by nickel nanoparticles. The results suggest that QCM-coated PAN/nickel nanofiber composites show great potential for the design of highly sensitive and selective methanol gas sensors.},

key = {Alcohols,Nanofibers,Nanoparticles,Nickel,Sensors},

keywords = {Alcohols, Nanofibers, nanoparticles, Nickel, openQCM Wi2, QCM, Quartz Crystal Microbalance, sensors},

pubstate = {published},

tppubtype = {article}

}

@article{qi2023porous,

title = {Porous Cellulose Thin Films as Sustainable and Effective Antimicrobial Surface Coatings},

author = {Shaojun Qi and Ioannis Kiratzis and Pavan Adoni and Aekkachai Tuekprakhon and Harriet James Hill and Zania Stamataki and Aneesa Nabi and David Waugh and Javier Rodriguez Rodriguez and Stuart Matthew Clarke and others},

url = {https://pubs.acs.org/doi/full/10.1021/acsami.2c23251},

doi = {https://doi.org/10.1021/acsami.2c23251},

year  = {2023},

date = {2023-03-29},

urldate = {2023-01-01},

journal = {ACS Applied Materials & Interfaces},

publisher = {ACS Publications},

abstract = {In the present work, we developed an effective antimicrobial surface film based on sustainable microfibrillated cellulose. The resulting porous cellulose thin film is barely noticeable to human eyes due to its submicrometer thickness, of which the surface coverage, porosity, and microstructure can be modulated by the formulations and the coating process. Using goniometers and a quartz crystal microbalance, we observed a threefold reduction in water contact angles and accelerated water evaporation kinetics on the cellulose film (more than 50% faster than that on a flat glass surface). The porous cellulose film exhibits a rapid inactivation effect against SARS-CoV-2 in 5 min, following deposition of virus-loaded droplets, and an exceptional ability to reduce contact transfer of liquid, e.g., respiratory droplets, to surfaces such as an artificial skin by 90% less than that from a planar glass substrate. It also shows excellent antimicrobial performance in inhibiting the growth of both Gram-negative and Gram-positive bacteria (Escherichia coli and Staphylococcus epidermidis) due to the intrinsic porosity and hydrophilicity. Additionally, the cellulose film shows nearly 100% resistance to scraping in dry conditions due to its strong affinity to the supporting substrate but with good removability once wetted with water, suggesting its practical suitability for daily use. Importantly, the coating can be formed on solid substrates readily by spraying, which requires solely a simple formulation of a plant-based cellulose material with no chemical additives, rendering it a scalable, affordable, and green solution as antimicrobial surface coating. Implementing such cellulose films could thus play a significant role in controlling future pan- and epidemics, particularly during the initial phase when suitable medical intervention needs to be developed and deployed.},

key = {cellulose, film, antimicrobial, evaporation, SARS-CoV-2, robustness},

keywords = {antimicrobial, cellulose, evaporation, film, openQCM NEXT, QCM, QCM-D, Quartz Crystal Microbalance, robustness, SARS-CoV-2},

pubstate = {published},

tppubtype = {article}

}

@article{bulut2023novel,

title = {A Novel Peptide-Based Detection of SARS-CoV-2 Antibodies},

author = {Aliye Bulut and Betul Z Temur and Ceyhun E Kirimli and Ozgul Gok and Bertan K Balcioglu and Hasan U Ozturk and Neval Y Uyar and Zeynep Kanlidere and Tanil Kocagoz and Ozge Can},

url = {https://www.mdpi.com/2313-7673/8/1/89},

doi = {https://doi.org/10.3390/biomimetics8010089},

year  = {2023},

date = {2023-02-22},

urldate = {2023-02-22},

journal = {Biomimetics},

volume = {8},

number = {1},

pages = {89},

publisher = {MDPI},

abstract = {The need for rapidly developed diagnostic tests has gained significant attention after the recent pandemic. Production of neutralizing antibodies for vaccine development or antibodies to be used in diagnostic tests usually require the usage of recombinant proteins representing the infectious agent. However, peptides that can mimic these recombinant proteins may be rapidly utilized, especially in emergencies such as the recent outbreak. Here, we report two peptides that mimic the receptor binding domain of the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and investigate their binding behavior against the corresponding human immunoglobulin G and immunoglobulin M (IgG and IgM) antibodies in a clinical sample using a quartz crystal microbalance (QCM) sensor. These peptides were immobilized on a QCM sensor surface, and their binding behavior was studied against a clinical serum sample that was previously determined to be IgG and IgM-positive. It was determined that designed peptides bind to SARS-CoV-2 antibodies in a clinical sample. These peptides might be useful for the detection of SARS-CoV-2 antibodies using different methods such as enzyme-linked immunosorbent assay (ELISA) or lateral flow assays. A similar platform might prove to be useful for the detection and development of antibodies in other infections.},

key = {peptide mimetics, SARS-CoV-2, biosensor, quartz crystal microbalance, antibody detection},

keywords = {antibody detection, biosensors, peptide mimetics, QCM, Quartz Crystal Microbalance, SARS-CoV-2},

pubstate = {published},

tppubtype = {article}

}

@article{hajizadehmotlagh2023wearable,

title = {Wearable Resonator-Based Respirable Dust Monitor for Underground Coal Mines},

author = {Mandana Hajizadehmotlagh and Dorsa Fahimi and Anuj Singhal and Igor Paprotny},

url = {https://ieeexplore.ieee.org/abstract/document/10047920},

doi = {https://doi.org/10.1109/JSEN.2023.3241601},

year  = {2023},

date = {2023-02-16},

urldate = {2023-02-16},

journal = {IEEE Sensors Journal},

volume = {23},

number = {7},

pages = {6680--6687},

publisher = {IEEE},

keywords = {Airborne, Diesel Exhaust, Dust, gravimetry, openQCM, QCM, Quartz Crystal Microbalance, Respirable Coal Dust},

pubstate = {published},

tppubtype = {article}

}

@article{armesenhanced,

title = {Enhanced Adsorption of Epoxy-Functional Nanoparticles onto Stainless Steel Significantly Reduces Friction in Tribological Studies},

author = {Dr. Csilla György and Dr. Paul M. Kirkman and Dr. Thomas J. Neal and Dr. Derek H. H. Chan and Megan Williams and Dr. Timothy Smith and Dr. David J. Growney and Prof. Steven P. Armes},

url = {https://onlinelibrary.wiley.com/doi/10.1002/anie.202218397},

doi = {https://doi.org/10.1002/anie.202218397},

year  = {2023},

date = {2023-01-18},

urldate = {2023-01-18},

journal = {Angewandte Chemie International Edition},

publisher = {Wiley Online Library},

abstract = {Epoxy-functional sterically-stabilized diblock copolymer nanoparticles (~27 nm) are prepared via RAFT dispersion polymerization in mineral oil. Nanoparticle adsorption onto stainless steel is examined using a quartz crystal microbalance. Incorporating epoxy groups within the steric stabilizer chains results in a near two-fold increase in the adsorbed amount, Γ, at 20 °C (7.6 mg m-2) compared to epoxy-core functional nanoparticles (3.7 mg m-2) or non-functional nanoparticles (3.8 mg m-2). A larger difference in Γ is observed at 40 °C; this suggests chemical adsorption of the nanoparticles rather than merely physical adsorption. A remarkable near five-fold increase in Γ is observed for larger (~50 nm) epoxy-functional nanoparticles compared to non-functional nanoparticles (31.3 vs. 6.4 mg m-2, respectively). Tribological studies conducted at 60-120 °C confirm that the adsorption of epoxy-functional nanoparticles leads to a significant reduction in the friction coefficient.},

key = {QCM-D, nanoparticles},

keywords = {epoxy-functional noparticles, nanoparticles, polymerization, polymerization-induced, QCM-D, Quartz Crystal Microbalance, RAFT, self-assembly, stainless steel},

pubstate = {published},

tppubtype = {article}

}

@article{aflaha2022improving,

title = {Improving ammonia sensing performance of quartz crystal microbalance (QCM) coated with nanofibers and polyaniline (PANi) overlay},

author = {Rizky Aflaha and Henny Afiyanti and Zhafirah Nur Azizah and Hanif Khoirudin and Aditya Rianjanu and Ahmad Kusumaatmaja and Roto Roto and Kuwat Triyana},

url = {https://www.sciencedirect.com/science/article/pii/S2590137022001935},

doi = {https://doi.org/10.1016/j.biosx.2022.100300},

year  = {2022},

date = {2022-12-23},

urldate = {2022-01-01},

journal = {Biosensors and Bioelectronics: X},

pages = {100300},

publisher = {Elsevier},

abstract = {Ammonia gas sensors with high sensitivity, good selectivity, and superior stability continue to be developed to monitor ammonia levels in the air. In this study, we developed a sensor based on a quartz crystal microbalance coated with polyvinyl acetate (PVAc) nanofiber overlaid with a polyaniline (PANi) nanocomposite to increase the sensitivity and selectivity of the sensor. The morphology and chemical composition of the fabricated nanofibers were examined by scanning electron microscopy and Fourier transform infrared spectroscopy. PANi nanocomposites were shown to stick to nanofiber, and nanofiber became many active groups after PANi overlay. The QCM sensor coated with the PVAc nanofiber overlaid with 0.05% PANi (PVAc/PANi5) exhibited the highest sensitivity of 0.297 Hz/ppm. This value was increased 5.2 times compared to the sensor without the PANi overlay (0.055 Hz/ppm). The PVAc/PANi5 sensor exhibited good reproducibility, repeatability, and reversibility. Moreover, a rapid response (36 s) and recovery (26 s) time were observed. The sensor also showed good selectivity towards other analytes and was proven to have good long-term stability during two months of testing. This finding may potentially be an alternative method for increasing the ammonia-sensing performance of a sensor through overlaying.},

key = {Polyvinyl acetate, Polyaniline, Ammonia, Quartz crystal microbalance, Nanofiber},

keywords = {Ammonia, Nanofiber, Polyaniline, Polyvinyl acetate, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{matsumoto4096144rheology,

title = {Rheology of the Electric Double Layer In Ionic Liquid Solutions: Effects of Ion Concentration and Anion Structures},

author = {Atsushi Matsumoto and Ryota Yoshizawa and Riccardo Funari and Osamu Urakawa and Tadashi Inoue and Amy Q Shen},

url = {https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4096144},

doi = {https://dx.doi.org/10.2139/ssrn.4096144},

year  = {2022},

date = {2022-04-28},

urldate = {2022-04-28},

journal = {Available at SSRN 4096144},

abstract = {Ionic liquids (IL) are molten salts with melting temperatures below 100°C. Combined with other unique properties such as high thermal and electrochemical stability, non-volatility and high ionic conductivity, they have been used as electrolytes in batteries and lubricants, where the viscoelasticity of the electric double layer (EDL) plays an important role. Due to the small length scale of EDL thickness, it has been challenging to characterize their viscoelastic properties at nanoscale. Herein, by using a quartz crystal microbalance (QCM), we measure the changes in the resonant frequency and energy dissipation of a gold-coated quartz crystal on which IL solutions are deposited. Since the gold surface of the quartz crystal is negatively charged at an open circuit potential, we can estimate the loss modulus of the EDL near the charged surface through a wave propagation model. Using this approach, we investigate the viscoelastic properties of the EDL formed on the quartz crystal from three ionic liquids with different anions: 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Bmim-TFSI); 1-butyl-3-methylimidazolium trifluoromethanesulfonate (Bmim-TfO); 1-butyl-3-methylimidazolium tetrafluoroborate (Bmim-BF4). We find that the loss modulus of the EDL increases rapidly with increasing ionic liquid concentrations in the low concentration regime, but reaches about 3 orders of magnitude larger than the loss modulus of the bulk solution in the higher concentration regime. This behavior is independent of the type of anions. Our results can provide useful information on the rheological properties of the EDL in IL solutions, optimizing IL-based material design with improved system performances.},

keywords = {Electric Double Layer, Electrostatic Screening, Ionic Liquid, openQCM Q-1, Quartz Crystal Microbalance, Rheology, Viscoelastic Properties},

pubstate = {published},

tppubtype = {article}

}

@article{saffari2022quartz,

title = {A quartz crystal microbalance biosensor based on polyethylenimine-modified gold electrode to detect hepatitis B biomarker},

author = {Zahra Saffari and Mina Sepahi and Reza Ahangari-Cohan and Mehdi Khoobi and Mojtaba Hamidi-Fard and Amir Ghavidel and Mohammad Reza Aghasadeghi and Dariush Norouzian},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0003269722004419},

doi = {https://doi.org/10.1016/j.ab.2022.114981},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Analytical Biochemistry},

pages = {114981},

publisher = {Elsevier},

abstract = {Biomarkers-based QCM-biosensors are suitable tools for the label-free detection of infectious diseases. In the current study, a QCM-biosensor was developed for the detection of HBsAg. Briefly, anti-HBsAg antibodies were covalently bound to the primary amines after PEI and thiolated-PEI surface modifications of gold-electrode. After RSM optimization, the statistical analysis revealed no significant difference between the immobilization yields of modified layers. Therefore, the PEI-modified QCM-biosensor was selected for further analysis. The PEI-surface was evaluated by FESEM, AFM, ATR-FTIR, and CA measurement. The surface hydrophilicity and its roughness were increased after PEI-coating. Also, FTIR confirmed the PEI-layering on the gold-surface. RSM optimization increased the antibody immobilization yield up to 80%. The QCM-biosensor showed noteworthy results with a wide dynamic range of 1–1 × 103 ng/mL, LOD of 3.14 ng/mL, LOQ of 9.52 ng/mL, and detection capability in human-sera, which were comparable with the ELISA. The mean accuracy of the QCM-biosensor was obtained at 91% when measured by the spike recovery test using human-sera. The biosensor was completely regenerated using 50 mM NaOH and 1% SDS. The benefits provided by the developed biosensor such as broad dynamic range, sensitivity, selectivity, stability, regenerate ability, and low cost suggest its potential application for the non-invasive and timely monitoring of HBV-biomarker.},

key = {Hepatitis B Biomarker, Biosensor, Quartz crystal microbalance, Polyethylenimine, Gold electrode},

keywords = {biosensors, Hepatitis B Biomarker, Polyethylenimine, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}