Sensitive I-V Biosensor Using DC Sputtered Nano-ZnO on PVA/FTO Thin Film as an Innovative Composite Transducer for Glucose Biosensing

Nanostructured zinc oxide (Nano-ZnO) was sputtered by reactive direct current (DC) magnetron sputtering system on a pre-covered fluorinated-tin oxide (FTO) conductive layer by spin-coated polyvinyl alcohol (PVA) at the optimized instrumental deposition conditions, as an efficient medium for glucose oxidase (GOx) enzyme covalent immobilization via covalent linking to the exposed PVA –OH groups through cyanuric chloride (GOx/Nano-ZnO/PVA/FTO), designed for glucose biosensing by the role of PVA as an electrostatic repulsive layer for the anionic interferents at the biological pH. The structural and electrochemical analyses such as Field emission-scanning electron microscopy (FE-SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and I-V techniques have been applied for morphology assessment of modified electrode s surface and electrochemical behavior of glucose on the fabricated GOx/Nano-ZnO/PVA/FTO biosensor. The I-V results indicated good sensitivity for glucose detection (0.041 mA per mM) within 0.2 – 20 mM and limit of detection was as 2.0 M. We believe that such kind of bio-devices has possessed a prominent potential to trace The number of bio-compounds in biological fluids along with excellent accuracy, selectivity, and precise analysis. A fast response of fabricated GOx/Nano-ZnO/PVA/FTO biosensor (less than 3 seconds (s)), can usually allow a real-time analysis.