固相萃取-高效液相色谱-质谱法测定污水中糖皮质激素

Determination of Glucocorticoids in Wastewater by Orthogonal Test Solid Phase Extraction-High Performance Liquid Chromatography-Mass Spectrometer

建立了同时测定污水中7种糖皮质激素的固相萃取-超高效液相色谱串联质谱的分析方法。利用单因素实验优化固相萃取影响因素:洗脱液、洗脱体积、水样pH值及淋洗液。在此基础上,进行L9(34)正交实验。通过直观分析和方差分析区分主次因素,确定了最佳固相萃取条件:洗脱剂为乙酸乙酯,洗脱剂用量为10mL,pH=5.0,清洗剂为20%甲醇。7种糖皮质激素的检出限为1.56～10.59ng/L;在20～100ng/L的3个添加水平范围内的平均回收率为72.5%～101.4%,相对标准偏差(RSD)小于10.9%。

A comprehensive analytical method based on solid-phase extraction （SPE） and ultra performance liquid chromatography-electrospray tandem mass spectrometry （UPLC-MS/MS） has been developed for the simultaneous determination of seven glucocorticoids in wastwater sample. Several single factor experiments were applied to analyze the effect of the solvent and volume used for elution, pH adjustment of the water sample, and the wash solution on SPE. Based on the single factor tests, the L9 （34） orthogonal test was used to further optimize extraction parameters. The primary and secondary factors were distinguished by visual analysis and analysis of variance. The optimum extraction process was as follows： eluting solvent was ethyl acetate, elution volume was 10mL, the pH value was 5.0 and washing solvent was 20% （V/V） methanol in HPLC grade water. The correlation coefficient （r2） of the calibration curve was over 0. 9976, in linear range of 1- 100 μg/L. The limits of detection （LOD） were between 1.56 and 10.59 ng/L. The recoveries at the spiked level of 20-100 ng/L were 72.48% to 101.42%, with the relative standard deviation （RSD） less than 10.9%.