液液小体积萃取气相色谱法测定水中丙烯酰胺

文章建立了溴化衍生-液液小体积萃取-气相色谱法-电子捕获检测器(GC-ECD)测定水中丙烯酰胺的方法。优化了前处理步骤,缩短了样品的处理时间,减少了试剂和样品的使用量。取20 mL水样,分别加入H2SO4、KBrO3、KBr,4℃下反应至少30 min,丙烯酰胺与新生溴反应生成2,3-二溴丙酰胺。加入Na2S2O3去除多余的溴,加无水硫酸钠于室温下溶解盐析,用2.0 mL乙酸乙酯萃取,取上层萃取液GC-ECD分析。用衍生物2,3-二溴丙酰胺的响应峰面积对水中丙烯酰胺的质量浓度绘制工作曲线,相关系数达到0.999 47。方法适用于饮用水、地表水中丙烯酰胺的测定,检出限可达到0.026μg/L,相对标准偏差RSD为2.70%,加标回收率为80.67%¹00.43%。

Determination of Acrylamide in Water by Liquid-Liquid Small Volume Extraction Combined with Gas Chromatography

Method of determination of acrylamide in water by liquid-liquid small volume extraction combined with gas chromatography(GC-ECD)was proposed.The preprocessing was optimized,shortening the processing time and reducing the usage amount of reagent and sample water.H2SO4,KBrO3 and KBr were added into 20 mL water and reacted for at least 30 min under the temperature 4 ℃,and acrylamide reacted with bromine to 2,3-dibromopropionamide.Na2S2O3 was added to remove the extra bromine and Na2SO4 was dissolved at room temperature.The sample was extracted with 2.0 mL ethyl acetate and the extract was detected by GC-ECD.Calibration curve was established with the responding peak’s area of 2,3dibromopropionamide vs the concentration of acrylamide in water,with correlation coefficient 0.999 47.The method is applicable to the determination of acrylamide in drinking water and surface water with the detection limits 0.026 μg/L,relative standard deviation 2.70% and average recovery in the range of 80.67%~100.43%.