Construction and electrochemical behavior of hemoglobin sensor based on ZnO doped carbon nanofiber modified electrode

Abstract

In this paper zinc oxide (ZnO) doped carbon nanofiber (CNF) was synthesized and used for electrode modification with hemoglobin (Hb) immobilized on the surface of carbon ionic liquid electrode (CILE). Ultraviolet–visible (UV–Vis) and Fourier transform infrared spectroscopic studies showed that Hb maintained its native structure in the composite film without denaturation, indicating that the modified materials had good biocompatibility. On the modified electrode (Nafion/Hb/ZnO-CNF/CILE), direct electron transfer of Hb was achieved with well-shaped and enhanced redox waves, and electrochemical behaviors of Hb were investigated in detail. Nafion/Hb/ZnO-CNF/CILE exhibited excellent electrochemical catalytic ability to the reduction of trichloroacetic acid (TCA) and NaNO2, as indicated by a linear relationship between peak current and concentration of analytes. The biosensor was applied to the quantitative analysis of TCA in various samples with good recovery. Experimental results demonstrated the potential applications of ZnO-CNF nanocomposite as a new generation of electrochemical biosensors.