Uniform sputtered nano porous zinc oxide (Nano-ZnO) thin film on the conductive fluorinated-tin oxide
(FTO) layer was applied to immobilize urease enzyme (Urs) for urea detection. Highly uniform nanoporous
ZnO thin film were obtained by reactive radio frequency (RF) magnetron sputtering system at the
optimized instrumental deposition conditions. Characterization of the surface morphology and roughness of ZnO thin film by field emission-scanning electron microscopy (FE-SEM) exhibit scavities of
nanoporous film as an effective biosensing area for enzym eimmobilization. Step by step monitoring of FTO/NanoZnO/Urs biosensor fabrication were performed using electrochemical methods such
as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. Fabricated
FTO/Nano-ZnO/Urs biosensor was used for urea determination using EIS experiments.The impedimetric results show high sensitivity for urea detection with in 0.83–23.24 mM and limit of detection as 0.40mM.