2′,7′-二氯荧光素荧光法测定环境水样中的酚

A Fluorimetric Method for The Determination of Phenols in Waste Water with 2′,7′Dichlorofluorescein

报道了以２′，７′－二氯荧光素（ＤＣＦ）为指示剂，荧光法间接测定痕量酚的新方法。在０．５ｍｏｌ／ＬＨ２ＳＯ４介质中，Ｂｒ－和ＢｒＯ－３反应生成Ｂｒ２，Ｂｒ２与２′，７′－二氯荧光素反应，使２′７′－二氯荧光素荧光猝灭，当加入酚时，酚的溴代反应使体系荧光增强。ｐＨ４．０～６．０范围内，该体系激发波长，发射波长分别为λｅｘ５０５ｎｍ，λｅｍ５２０ｎｍ。酚浓度在１．６～５２ｎｇ／Ｌ范围内呈线性关系，检出限为１．６ｎｇ／Ｌ。本法选择性好，用于环境水样中酚的测定，结果满意。

A highly sensitive and selective fluorimetric new method has been developed for the determination of trace amounts of phenols with 2′,7′-dichlorofluorescein as the fluorogenic reagent(λex=505, λem=520nm) at pH 4.0～6.0. Br- reacts with BrO-3 in sulfuric acid solution (0.5mol/L) to produce bromine (Br2), which then reacts with 2′.7′-dichlorofluorescein resulting in fluorescence quenthing. If phenols are present, the fluorescence intensity of the solution increases with increasing concontration of phenols. The linear range is 1.6～52ng/L, the detection limit is 1.6ng/L. It has been applied to the determination of phenols in environmental water samples with satisfactory results.