Polymer of chitosan with ZnO addition to optimize high responsivity and sensitivity in sensor film

Abstract

Coating of polymer chitosan as sensor film on copper electrode substrate (Cu) has become a concern of research development to improve responsivity, sensitivity, and economic value to detect hazardous preservatives in food, especially formalin. This study aims to enhance the activities of sensor for more responsive and higher sensitivity by adding metal oxide as an active agent. Chitosan thin film is prepared by 1.5% chitosan dissolved with 2% acetic acid and modified with active compound ZnO. The addition of ZnO NPs metal oxide is to improve sensitivity which viewed from SEM characterization results, the surface of morphology is smoother and flat on the surface of chitosan. Characterization of FT-IR showed ZnO was perfectly bound to amine bond of chitosan structure. The research method was conducted by cyclic voltammetry analysis to find out the results test of sensor sensitivity. The results showed chitosan-ZnO film sensor provides the best sensitivity on modification conditions of ZnO NPs 0.6% and 0.8%. Linearity analysis of sensor provides ideal value obtained at R-square value of 0.9886. Thus, it can be concluded that chitosan-ZnO thin-film sensor is hugely responsive to be used as an electrode sensor for detecting hazardous chemical compounds in food. Chitosan-ZnO film sensor can provide high activity as a biosensor electrode for detecting harmful compounds in foods that are sensitive, responsive, and has economic value.