Voltammetry of Dehaloperoxidase on Self-Assembled Monolayers: Reversible Adsorptive Immobilization of a Globin
Dehaloperoxidase (DHP), a monomeric hemoglobin, was adsorptively immobilized under low ionic strength conditions on binary self-assembled monolayers composed of OH- and COOH-terminated alkylthiols. Voltammetry of its Fe(III)/Fe(II) reactions revealed adsorbed DHP to be electroactive and native under both anaerobic and aerobic conditions. The chemically reversible nature of the adsorptive immobilization was established from voltammetric desorption/re-adsorption experiments. Cyclic voltammetric determination of electroactive surface concentration uncovered an unusual inverse scan rate dependence that was rationalized by means of Hoffman's dynamic docking electron transfer model [Z.-X. Liang et al., J. Am. Chem. Soc. 126 (2004) 2785]. This result represents the first evidence for dynamic docking control of protein electron transfer in an electrochemical setting.
Published in Electrochemistry Communications, Volume 26, 2013, pages 67-70.
© Electrochemistry Communications 2013, Elsevier B.V.