分散液液微萃取-衍生化高效液相色谱-荧光检测法测定环境水样中4种酚类内分泌干扰物

摘要

为实现小体积环境水样中酚类化合物的准确、快速、高灵敏测定，通过分散液液微萃取（ DLLME）和荧光衍生化的结合，建立了高效液相色谱-荧光检测（HPLC-FLD）双酚 A、壬基酚、辛基酚和对特辛基酚的分析方法。考察并优化了 DLLME 和衍生化条件，结果表明，最优的 DLLME 条件为萃取剂氯仿用量70μL，分散剂乙腈用量400μL，漩涡振荡3 min，高速离心2 min。以2-[2-（7H-二苯并[a，g]咔唑-乙氧基）]-乙基氯甲酸酯（DBCEC-Cl）为柱前衍生试剂，在 pH 10.5的 Na2 CO3-NaHCO 3缓冲液/乙腈溶液、50℃下衍生反应3 min 得到稳定的衍生产物，于10 min 内实现了4种酚衍生物的分离。方法的检出限为0.9~1.6 ng / L，定量限为3.8~7.1 ng / L，具有良好的线性、精密度和回收率，与以往报道的方法相比具有一定的优势和实用性，可用于造纸厂废水、湖水、生活废水、自来水中4种酚类内分泌干扰物的测定。%To achieve accurate,fast and sensitive detection of phenolic endocrine disruptors in small volume of environmental water samples,a method of dispersive liquid-liquid microextrac-tion(DLLME)coupled with fluorescent derivatization was developed for the determination of bisphenol A,nonylphenol,octylphenol and 4-tert-octylphenol in environmental water samples by high performance liquid chromatography-fluorescence detection( HPLC-FLD). The DLLME and derivatization conditions were investigated,and the optimized DLLME conditions for small volume of environmental water samples(pH 4. 0)at room temperature were as follows:70 μL chloroform as extraction solvent,400 μL acetonitrile as dispersing solvent,vortex mixing for 3 min,and then high-speed centrifugation for 2 min. Using 2-[2-(7H-dibenzo[ a,g]carbazol-7-yl)-ethoxy]ethyl chloroformate( DBCEC-Cl)as precolumn derivatization reagent,the stable derivatives of the four phenolic endocrine disruptors were obtained in pH 10. 5 Na 2 CO 3-NaHCO 3 buffer / acetonitrile at 50 ℃ for 3 min,and then separated within 10 min by HPLC-FLD. The lim-its of detection( LODs)were in the range of 0. 9 - 1. 6 ng / L,and the limits of quantification (LOQs)were in the range of 3. 8-7. 1 ng / L. This method had perfect linearity,precision and recovery results,and showed obvious advantages and practicality comparing to the previously reported methods. It is a convenient and validated method for the routine analysis of phenolic endocrine disruptors in waste water of paper mill,lake water,domestic wastewater,tap water,etc.