Real-time kinetic analysis and detection of glycated hemoglobin A1c using a quartz crystal microbalance-based aptasensor

Glycated hemoglobin (HbA1c) is an important biomarker for the long-term diagnosis and monitoring of diabetes mellitus. Here, an aptamer specific to HbA1c was covalently functionalized onto a QCM substrate via mixed self-assembled monolayers (SAMs). A portable QCM equipped with a liquid-flow module was used to investigate the biospecificity, sensitivity and interaction dynamics of the aptamer-functionalized surfaces. The aptasensor showed highly specific recognition of HbA1c with an equilibrium dissociation constant of 57.99 nM, a linear detection range from 13 to 108 nM, and a limit of detection of 26.29 nM.