Studies on direct electron transfer and biocatalytic properties of hemoglobin in polytetrafluoroethylene film

Hemoglobin (Hb) was incorporated in polytetrafluoroethylene (PTFE) film cast on the glassy carbon electrode. A pair of well-defined and quasi-reversible cyclic voltammetric peaks was obtained, reflecting the direct electron transfer of Hb. Ultraviolet visible spectroscopy showed Hb in PTFE film remained its secondary structure similar to the native state. Scanning electron microscopy demonstrated the morphology of Hb–PTFE film very different from the Hb and PTFE films alone. The immobilized protein retained its biocatalytic activity to the reductions of nitric oxide and hydrogen peroxide, providing a better perspective of the third generation biosensors.