Acta Phys. -Chim. Sin. ›› 2007, Vol. 23 ›› Issue (08): 1247-1251.doi: 10.3866/PKU.WHXB20070820

• ARTICLE • Previous Articles     Next Articles

Direct Electrochemistry of Hemoglobin at Room Temperature Ionic Liquid [BMIM]PF6 Modified Carbon Paste Electrode

SUN Wei; GAO Rui-Fang; WANG Dan-Dan; JIAO Kui   

  1. College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, Shandong Province, P. R. China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, P. R. China
  • Received:2007-01-02 Revised:2007-03-26 Published:2007-08-03
  • Contact: SUN Wei

Abstract: Direct electrochemistry of hemoglobin (Hb) was investigated on a roomtemperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) modified carbon paste electrode (CILE). The CILE was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). Hb was immobilized on the CILE with a chitosan-bentonite composite film and a pair of well-defined, quasi-reversible cyclic voltammetric redox peaks was obtained, which was characteristics of Hb Fe(III)/Fe(II) redox couples. The formal potential (E0’), the electron transfer number (n), and transfer coefficient (α) were calculated as -0.352 V (vs SCE), 0.885, and 0.578, respectively, which indicated that one electron was transferred between heme group of Hb and the electrode. The average apparent heterogeneous electron transfer rate constant (ks) obtained for Hb was 0.149 s-1.

Key words: Direct electrochemistry, Carbon paste electrode, Hemoglobin, Room temperature ionic liquid, 1-butyl-3-methylimidazoliumhexafluorophosphate