An Amperometric Biosensor Based on a Multi-Nanoporous SnO2/HRP/Chitosan for Detection of Hydrogen Peroxide in Human Urine Samples

A new amperometric biosensor fabricated from a multi-nanoporous SnO2 and HRP was trialled. The multiporous SnO2 nanofiber was fabricated in the research lab. Horseradish peroxidase was co-immobilized on a glassy carbon electrode with the multiporous SnO2 nanofiber and chitosan. The FESEM and EDX analysis were used to study the nanostructure and composition details of the nanofiber. Electrochemical results established that the immobilized HRP exhibited direct electrochemical behavior toward hydrogen peroxide (H2O2). The effects of pH, and applied potentials on the biosensor were also investigated. The limit of detection which was found to be 5 × 10–7 M with the linear range being between 5 × 10–6 M to 1.2 × 10–4 M of H2O2. For real sample analysis, this biosensor showed that the H2O2 concentration in the human urine can be monitored conveniently, where the interference is noted to be negligible.