ZnO-carbon active nanostructured thin film fabrication by spin coating technique for enzymatic urea biosensing

Spin coated zinc oxide (ZnO)-carbon active porous media on the Fluorine-doped Tin Oxide (FTO) coated glass is presented as an engaged nomination for novel application in enzymatic urea biosensor. Some correlations between the processing parameters spinning speed, spinning duration, volume of solution and ZnO:carbon active ratio and respective thin film characteristics were determined, then uniform ZnO-carbon active the uniform film was achieved at the optimum deposition conditions. FE-SEM was employed to investigate the morphology and hardness of ZnO-carbon active thin film. The FE-SEM image illustrates cavities of a thin film as an efficient transducer area for immobilization of urease enzyme (Urs). Stepwise study of FTO/ZnO-carbon active/Urs biosensor manufacturing was performed by voltammetric and impedimetric techniques. The results revealed a good sensitivity for impedimetric urea retrieval between 8.0-110.0 mg dL-1 with detection limit of 5.4 mg dL-1.