title: Direct electrochemistry of hemoglobin in dimethyldioctadecyl ammonium bromide film and its electrocatalysis to nitric oxide.
abstract: Hemoglobin (Hb) was successfully immobilized in dimethyldioctadecyl ammonium bromide (DOAB) film at pyrolytic graphite (PG) electrode. Electrochemical experiments revealed that Hb in DOAB film exhibited a pair of well-defined, quasi-reversible cyclic voltammetric peaks at about -0.160 V versus saturated calomel electrode (SCE) in pH 5.0 buffer, characteristic of the heme Fe(III)/Fe(II) redox couple of Hb. The electron transfer (eT) rate between Hb and the PG electrode was 0.10 s(-1). Positions of the Soret absorbance band indicated that the Hb retained its secondary structure and was similar to its native state. Furthermore, the Hb in DOAB film acted as a biological catalyst towards the reduction of nitric oxide (NO). The voltammetric response of NO at the Hb-DOAB modified electrode could be used to determine the concentration of NO in solution.
authors.affiliation: Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Hankou Road 22, Nanjing 210093, P.R. China.
authors.forename: Xinjian
authors.initials: X
authors.lastname: Liu
authors.forename: Libin
authors.initials: L
authors.lastname: Shang
authors.forename: Ziyi
authors.initials: Z
authors.lastname: Sun
authors.forename: Genxi
authors.initials: G
authors.lastname: Li
mesh_terms: D015374:Biosensing Techniques; D002384:Catalysis; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D004583:Electrons; D006418:Heme; D006454:Hemoglobins / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry; D009569:Nitric Oxide / Q000737:chemistry*; D010084:Oxidation-Reduction; D017433:Protein Structure, Secondary; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D006454:Hemoglobins; D000644:Quaternary Ammonium Compounds; C015831:dimethyldioctadecylammonium; D009569:Nitric Oxide; D006418:Heme; D007501:Iron