Electrochemical Detection of Influenza A Virus using Zinc Oxide Nanostructures-based DNA Immunosensor

In this study, we report a zinc oxide (ZnO) nanostructures-based DNA immunosensor for label free detection of influenza A virus H1N1. Two different morphologies of ZnO nanostructures such as zinc oxide nanorods (ZnO-nRs) and zinc oxide nanoflowers (ZnO-nFs) were successfully synthesized by a simple low-temperature route in the absence of surfactants. The as-synthesized ZnO nanostructures were characterized to identify their morphology by X-ray diffraction and scanning electron microscopy. Aqueous solutions of ZnO-nRs and ZnO-nFs were deposited on ITO-coated glass substrate and conjugated via covalent bonding with probe DNAs specific to H1N1 influenza virus. Chronoamperometry was performed to detect the H1N1 virus concentration from 10 pM to 5 nM in phosphate buffered saline (PBS). The DNA immunosensor showed linear behaviour with logarithmic H1N1 concentration (R2 =0.93), with the limit of detection of 2.54 pM