Highly Sensitive Safrole Sensor Based on Chitosan Modified Electrospun Polyacrylonitrile Nanofibers

Safrole is one of the main precursors in the production of an amphetamine-type stimulant (ATS) drug, N-methyl-3,4-methylene-dioxyamphetamine (MDMA or ecstasy). In the practical application, safrole should be able to be detected rapidly and accurately. This paper aims to report the main characteristics of quartz crystal microbalance (QCM) coated with polyacrylonitrile (PAN) nanofibers to detect safrole. Here, the fibers were prepared using electrospinning and deposited directly on both Au surfaces of the QCM followed by drop coating with chitosan solution. For comparison, we also characterized the QCM coated with PAN nanofibers only and the QCM coated with drop cast chitosan only. As a result, the sensors without combination of PAN nanofibers and chitosan exhibited very low sensitivity, while that of the combination presented an excellent response to detecting safrole vapor at ambient temperature. In more detail, the sensor with combination of PAN nanofibers and chitosan possesses excellent sensitivity of 0.119 Hz/ppm, good reversibility, fast response (40 s), with relatively stable and selective for safrole detection. Hence, such promising QCM sensors based on chitosan-modified electrospun polyacrylonitrile nanofibers could not only potentially allow for detecting safrole, but also flexibility in designing and developing novel QCM sensing systems for other drugs and narcotics. *Keywords: Quartz Crystal Microbalance; Safrole; Ecstasy; Precursor, Nanofiber polyacrylonitrile*