荧光摩尔吸收系数法测定洗护用品中烷基酚聚氧乙烯醚

摘要

A hybrid high performance liquid chromatographic method was developed for the determination of alkyphenol ethoxylates(NPnEO and OPnEO,n =0-30)in detergent products and cosmetics.Different types of samples were extracted by ultrasonic-assisted extraction using a mixture of acetonitrile-water(8 ∶ 2).The chromatographic separation was conducted with a reverse phase column of C18(Poroshell 120 EC-C18,75 mm ×4.6 mm,2.7 μm) coupled with a HILIC-Silia column (Atlantis HILIC Slica,250 mm ×4.6 mm,5 μm) by gradient elution using acetonitrile-10 mmoL/L ammonium acetate as mobile phase.The detection was performed with a fluorescence detector (FLD).A quantitative model was established based on fluorescence molar absorption coefficients of NPnEO and OPnEO.With the quantification of the hybrid standard solution of NPnEO and OPnEO,the fluorescence molar absorption coefficients of NPnEO and OPnEO were determined.The average molecular weight of NPnEO and OPnEO in real samples were measured,and the concentrations of the analytes were calculated with the fluorescence molar absorption coefficients.With this method,the average recoveries for APEOs ranged from 99.0％ to 105.7％ with relative standard deviations no more than 12.5％,and the limit of quantitation were both 40.0 mg/kg.%建立了洗涤用品和化妆品护理用品中烷基酚聚氧乙烯醚(NPnEO和OPnEO,n=0～30)的高效液相色谱分析方法.采用乙腈水溶液超声提取不同基质类型的洗涤用品和化妆品护理用品,利用快速反相C18柱(Poroshell 120 EC-C18,75 mm×4.6 mm,2.7μm)串联HILIC硅胶色谱柱(Atlantis HILIC Slica,250 mm×4.6mm,5 μm)对NPnEO和OPnEO的各单体及样品杂质进行有效分离,以乙腈-10 mmol/L醋酸铵溶液为流动相进行梯度洗脱,荧光检测器进行检测,建立了荧光摩尔吸收系数定量校正NPnEO和OPnEO的计算模型.通过测定NPnEO和OPnEO混合标准溶液,计算得到两者的荧光摩尔吸收系数.对样品中NPnEO和OPnEO的平均分子量进行测定,并利用荧光摩尔吸收系数对总峰面积进行校正定量.方法的回收率为99.0％～105.7％,相对标准偏差不大于12.5％,定量下限为40.0 mg/kg.该方法快速、准确、适用范围广,可用于各类洗涤用品和化妆品护理用品中烷基酚聚氧乙烯醚(NPnEO和OPnEO)含量的检测.