Biosensor for Hydrogen Peroxide Based on Chitosan and Nanoparticle Complex Film–Modified Glassy-Carbon Electrodes

Abstract

Abstract A biosensor for hydrogen peroxide was fabricated by co-immobilizing cadmium telluride (CdTe) nanoparticles, chitosan, and hemoglobin (Hb) matrix. There was a pair of nearly reversible redox peaks around −0.360 V, and the electrochemical behavior of Hb was a surface-controlled process, with an electron-transfer rate constant of 1.36 s−1 and surface coverage of 2.62 × 10−10 mol cm−2. Fourier transform infrared (FT-IR) spectra and ultraviolet–visible (UV-vis) spectra indicated that Hb sustained its natural conformation. It was demonstrated that Hb in the matrix kept its bioactivity and exhibited catalytic ability toward H2O2, with a response ranging from 7.44 × 10−6 to 6.95 × 10−4 M and a detection limit of 2.23 × 10−6 M.