VitaminK_1在水-有机溶剂中单电子还原电位的测定

Determination of One Electron Reduction Potential of Vitamin K_1 in Mixed Solvent

ＶｉｔａｍｉｎＫ１（ＶＫ１）是一种非常重要的脂溶性维生素，其止血功能已为人们所熟悉．下图显示在生物体内ＶＫ参与的止血过程，在这个氧化还原循环过程中，ＶＫＨ２环氧化变成ＶＫＯ与Ｇｌｕ(谷氨酸蛋白)羧化而转变成Ｇｌａ(γ-羧基谷氨酸蛋白)是同时发生的，但前一?..

The reaction process of VK1 and isopropanol radical has been investigated by using pulse radiolytical technique.It has been found that the reduction states of VK1 exist in two forms under different pH conditions,that are VK1H·(pH < 5.4) and VK (pH > 5.4),their maximum absorption peaks are 370 nm and 390 nm respectively.Selecting MV2+as the refereance,the one elec tron reduction potential of VK1 in N2 saturated aqueous isopropanol acetone mixed solvent and in N2O saturated water isopropanol has been determined as -266 and -279mV respectively.