电位法测定谷胱甘肽转移酶活性的研究

谷胱甘肽转移酶(GSTs)是生物体内一种重要的解毒酶,催化异源物与谷胱甘肽结合,有多种方法测定其活性,但都基于大分子产物。本实验基于H.Habig方法,探讨用氯离子选择电极,根据反应体系中Cl-浓度的变化来测定谷胱甘肽转移酶的活性。研究结果表明,利用透析膜包裹电极可以消除底物谷胱甘肽(GSH)对电极的干扰,生物反应体系中可能存在的离子、小分子(如Br-I、-、H2O2和Vc)对电极没有影响。此方法重现性良好,相对标准偏差为3.54%。

Study on the Determination of Glutathione S-Transferase Activity by Chronopotentiometry

Glutathione S-transferases(GSTs) are a family of cytosolic enzymes involved in the detoxification of a range of xenobiotic compounds by conjugation to glutathione.GSTs activity could be determined by many methods such as photometric analysis and fluorophotometric analysis,which are all focused on macromolecule products.In this paper,a simple method was used to determine glutathione(S-transferase) activity by chloride ion selective electrode.The principle of this method was based on Habig~(')s method and GSTs activity was expressed as the variability of concentration of Cl~(-) instead of C_(6)H_(3)O_(4)N_(2)-SG which is used in traditional method.Dialysis membrane was used to avoid the substrate of GSH interfering with the stability of electrode.The result showed that Br~(-),I~(-),H_(2)O_(2)and V_(c) had no effect on the stability of electrode.The proposed method has a good reproducibility with RSD of 3.54%.