Nanocrystalline TiO 2 particles film has been considered as an eminent matrix for the immobilization of biomolecules due to its high biocompatiability, high protein loading and special binding ability. The direct electron transfer process of hemoglobin was achieved at nanosized TiO 2 film electrode, in which a well defined redox peak of hemoglobin could be observed. However, this peak decreased with the presence of NO, indicating the electrochemical activity of hemoglobin was inhibited by the interation between hemoglobin and NO. While the further evidence revealed that such activity could be recovered after releasing NO from hemoglobin with electrochemical oxidation method.
