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.
This work was supported by the National Natural Science Foundation of China (Grant No. 30670553). We also thank the Analytical and Testing Center (Huazhong University of Science and Technology) for the help with measurements.