建立了金属络合衍生/高效液相色谱同时测定洗涤用品中乙二胺四乙酸（EDTA）和氮川三乙酸（NTA）的分析方法。样品经水提取,硝酸铜络合衍生,MAX阴离子交换固相萃取柱净化,经X-Bridge C18（4.6 mm×250 mm, 5 μm）色谱柱分离后,用高效液相色谱/二极管阵列检测器检测,以保留时间和紫外吸收光谱定性,外标法定量。结果表明,氮川三乙酸与乙二胺四乙酸在各自范围内呈良好的线性关系,相关系数（R 2）均大于0.999 7,检出限为10~20 mg/kg,定量限为25~50 mg/kg。添加水平为0.5~100.0 mg/L时平均回收率为89.8%~107.8%,相对标准偏差（RSDs,n=6）为1.11%~5.71%,该方法精密度好,准确度高,可满足相关检测需求。
A method for the determination of ethylenediamine tetraacetic acid（EDTA）and nitrilotriacetic acid（NTA）in detergent products was established using metal-complexing derivatization and high performance liquid chromatography. The samples were extracted with water, derivatized with Cu（NO3） 2, purified by MAX anion-exchange solid-phase extraction, separated on an X-Bridge C18（4.6 mm×250 mm, 5 μm） column, and detected by HPLC with a diode array detector. The retention time and UV absorption spectra were used for qualitation and the external standard method was used for quantitation. The results show that, under optimized conditions, the calibration curves show good linearity in respective ranges for NTA and EDTA with correlation coefficients（R 2）no less than 0.999 7. The LODs and LOQs are in the ranges of 10-20 mg/kg and 25-50 mg/kg, respectively. The recoveries of EDTA and NTA at the spiked levels of 0.5-100.0 mg/L are in the range of 89.8%-107.8% with the relative standard deviations（RSDs, n=6）are 1.11%-5.71%. With good precision and high accuracy, this method is suitable for the determination of EDTA and NTA in detergent products.
