Selenoprotein L-inspired nano-vesicular peroxidase mimics based onamphiphilic diselenides

In this study, we developed selenoprotein L-inspired nano-vesicular peroxidase mimics based onamphiphilic diselenides. Selenocystine (SeCyst) was used as the starting material for the synthesis offour liposomal membrane-compatible diselenide derivatives (R−Se−Se−R’) with two hydrophobic tailsand a polar part. The diselenide derivatives were successfully incorporated into the phosphatidylcholine(PC)-based nano-vesicular scaffold. The results of the particle diameter and zeta-potential measure-ments suggested that the functional diselenide moiety was placed around the outer surface, not in thehydrophobic interior, of the liposomal membrane structures. The GPx-like catalytic activity of the dis-elenide/PC liposomes was determined by the conventional NADPH method using glutathione as thereducing substrate. For three peroxide substrates, i.e., hydrogen peroxide, organic tert-butyl hydroperox-ide and cummen hydroperoxide, the cationic property-possessing diselenide derivatives in the PC-basedliposomes resulted in a higher catalytic activity in comparison to electrically neutral and anionic deriva-tives. Overall, the diselenide derivatives at the surface of a liposomal colloidal scaffold could exert aGPx-like catalytic activity in physiological aqueous media.