Electrochemical oxidation of selenocystine and selenomethionine

Department of Chemistry, Jinan University, Guangzhou 510632, China.
Colloids and surfaces B: Biointerfaces (Impact Factor: 4.15). 08/2009; 74(1):150-3. DOI: 10.1016/j.colsurfb.2009.07.010
Source: PubMed


Electrochemical oxidation of selenocystine (SeCys) and selenomethionine (SeMet), on a gold electrode was studied by cyclic voltammetry (CV), rotating disk electrode technique (RDE) and chronocoulometry (CC). In 0.2 mol/L HAc-NaAc (pH=3.90) supporting electrolyte, anodic peak I potential of SeCys and SeMet was 810 mV and 638 mV, respectively, and this electrode process was diffused controlled. The electrochemical oxidation process of SeCys, in which six electron-transfers were involved, yielded selenocystine selenoxide. The electrochemical oxidation process of SeMet, in which two electron-transfers were involved, yielded selemethionine selenoxide.

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