衍生化-气相色谱-质谱法测定染整助剂中的乙二胺四乙酸盐和二乙烯三胺五乙酸盐

Determination of EDTA and DTPA in dyeing and finishing auxiliaries with derivatization-gas chromatography-mass spectrometry

建立了乙二胺四乙酸盐（EDTA）和二乙烯三胺五乙酸盐（DTPA）衍生化成乙基酯的前处理方法以及气相色谱-质谱法测定乙基酯的方法。样品经甲酸酸化后,与乙醇发生酯化反应生成乙基酯,由正己烷提取,选择离子模式下由优化好的气相色谱-质谱进行定性定量分析。EDTA和DTPA质量浓度分别在0.2~20.0 mg/L和0.5~50.0 mg/L范围内线性关系良好,相关系数均不小于0.9991,两种不同阴性样品的3个不同浓度添加水平的平均回收率在91.6%~94.9%之间,相对标准偏差均不大于5.2%,EDTA和DTPA检出限分别为0.0609 mg/kg和0.145 mg/kg,定量限分别为0.194 mg/kg和0.476 mg/kg。方法能够满足染整助剂中EDT A和DT PA定性确证和准确定量的要求。

A method of treating EDTA and DTPA into ethyl ester and determining with gas chromatography-mass spectrometry（GC-MS） was developed. Sample was acidified with formic acid and esterified with ethanol,after extracting by hexane. The qualitative and quantitative analysis was performed by the optimized GC-MS under selective ion mode. The calibration curves showed good linearity in the concentration range of 0. 2 ~ 20. 0 mg/L and 0. 5 ~ 50. 0 mg/L for the EDTA and DTPA with correlation coefficients not less than 0. 9991. The average recoveries of EDTA and DTPA for spiked samples at three different concentration levels in two different negative samples ranged from 91. 6% to 94. 9 %,with relative standard deviation（RSDs） not more than 5. 2 %. The limits of detection of EDTA and DTPA were 0. 0609 mg/kg and 0. 145 mg/kg,and the limits of quantitation were0. 194 mg/kg and 0. 476 mg/kg. The established method is reliable,accurate and sensitive,which is suitable for the determination of EDTA and DTPA in dyeing and finishing auxiliaries.