title: Effects of hydrogen peroxide on the electrochemical decomposition of layer-by-layer thin films composed of 2-iminobiotin-labeled poly(ethyleneimine) and avidin.
abstract: The effects of hydrogen peroxide on the electrochemical decomposition of layer-by-layer thin films composed of 2-iminobiotin-labeled poly(ethyleneimine) (ib-PEI) and avidin were studied. An ib-PEI/avidin thin film prepared on the surface of a platinum (Pt) film-coated quartz resonator was electrochemically decomposed in the presence of hydrogen peroxide (H(2)O(2)) in the solution. The resonant frequency of the thin-film-deposited quartz resonator was increased upon application of electric potential (0.4-0.6 V vs Ag/AgCl) to the Pt layer, suggesting that the mass on the quartz resonator was decreased as a result of decomposition of the ib-PEI/avidin film. It was found that decomposition of the film is highly accelerated in the presence of H(2)O(2) compared to the decomposition in the same buffer solution without H(2)O(2), due to a pH change originating from electrochemical oxidation of H(2)O(2) on the Pt surface. The rate of electrochemical decomposition of the ib-PEI/avidin film was highly dependent on the concentration of H(2)O(2,) buffer capacity, and pH of the solution.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Sato
authors.forename: Yukihisa
authors.initials: Y
authors.lastname: Naka
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Anzai
mesh_terms: D001360:Avidin / Q000737:chemistry*; D015374:Biosensing Techniques; D001710:Biotin / Q000031:analogs & derivatives* / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry*; D011791:Quartz / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013194:Staining and Labeling; D013499:Surface Properties; D013997:Time Factors
chemical_list: D001360:Avidin; D011791:Quartz; D010984:Platinum; D001710:Biotin; D011094:Polyethyleneimine; D006861:Hydrogen Peroxide; C028072:2-iminobiotin