过氧化氢酶的荧光法测定及其在海洋环境污染评估中的应用

A New Method for the Determination of CAT and Its Application

建立了一种新的测定过氧化氢酶的方法.在酸性介质中,Fenton反应产生的羟基自由基(·OH)能将几乎无荧光的2,2′ 联吡啶氧化成强荧光物质,羟基化产物的最大激发和发射波长分别是340nm和430nm.过氧化氢酶(CAT)催化H2O2分解为H2O和O2,抑制Fenton反应,导致2,2′ 联吡啶羟基化反应产率降低,体系荧光强度减弱.体系荧光强度的减弱与过氧化氢酶的量成正比.用此法直接分析海洋生物样品的CAT活力,结果表明,该方法操作简便、测定快速,可作为一种简便的过氧化氢酶的测定方法.

A new method was developed for the determination of CAT. In pH=2.0 sulfuric acid solution, 2,2′bipyridine, an almost nonluminescent compound was transformed into a highly fluorescent compound (λex=340 nm, λem=430 nm) when attacked by ·OH generated by Fenton reaction. CAT acted as a catalyst for the decomposition of H2O2, producing H2O and O2, and restrained the production of ·OH and led to decrease in the fluorescence enhancement. The decrease of fluorescence intensity was quantitatively measured. This method has been applied to the determination of CAT in oyster humor.