Highly sensitive SAM modified electrospun zinc oxide nanofiber based label free biosensing platform

The present work demonstrates ultrasensitive, label free biosensor platform using Self Assembled Monolayer (SAM) modified Electrospun ZnO nanofibers. The inherent sensing ability of ZnO nanofibers is enhanced by modifying the fibers with 3-mercaptopropionic (MPA) acid. This role of MPA is to generate carboxylic acid (-COOH) group which can easily be functionalized with any protein molecule by a simple, well established crosslinking biochemistry. To synthesize the nanofibers electrospinning technique, a simple, low cost, robust technique, was utilized. The as-synthesized ZnO nanowires were characterized using Field emission-scanning electron microscopy (FE-SEM), Energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD). The performance of sensor was verified with standard Biotin-Streptavidin interaction as model system using Cyclic Voltammetry (CV). The sensor exhibits excellent sensitivity (613 μA/mg ml^-1/cm²) within 1 μgml^-1-1fgml^-1 of streptavidin with lfgml^-1 lower detection limit.