脂溶性维生素C衍生物及氮氧自由基在胶束中络合平衡常数的测定

The Determination of Equilibrium Constants of Liposoluble Derivatives of Vitamin C and Nitroxides in Micelles

我们最近对维生素C及其脂溶性衍生物在胶束中的抗氧化活性的研究发现,尽管它们在均相溶液中的活性基本相同,但在胶束中却相差很大,强烈地依赖于氧化剂氮氧自由基及抗氧化剂在胶束中的络合程度.因此,测定它们在胶束中的分配系数及络合平衡常数,对讨论生物抗氧化剂在胶束中的反应活性有重要意义.

In this paper the determination of equilibrium constants between piperidine nitroxides and vitamin C and its derivatives in SDS and CTAB micelles is reported. It was found that the magnitude of binding constants of the substrate with micelles is related not only to the lipophilici-ty of the substrate but also, under certain circumstances, to the electrostatic interaction between the substrate and the micelles. These results provide the rationale for the discussion on relevant kinetic studies in micellar systems.