基于硅藻土改性的磁性纳米材料分散固相萃取-高效液相色谱法测定尿中苯巯基尿酸

Determination of S-phenylmercapturic acid in urine by dispersive solid-phase extraction and HPLC based on diatomite bonded Fe_3O_4 magnetic nanocomposite

目的建立硅藻土改性磁性纳米材料分散固相萃取-高效液相色谱测定尿中苯巯基尿酸。方法尿样经过离心后,取5. 0 ml上清液,用盐酸调节pH值为1. 0,经硅藻土改性磁性纳米材料进行分散固相萃取后,分离出有机相,残渣用甲醇溶解并定容后注入高效液相色谱仪,经EC-C18反相色谱柱(150 mm×4. 6 mm,4μm)分离,紫外检测器检测,以保留时间定性,峰面积外标法定量。结果本法中苯巯基尿酸在0. 050 mg/L～1. 0 mg/L内线性关系良好,相关系数为0. 999 7,以3倍噪音值计算方法检出限为0. 028 mg/L,在0. 050 mg/L～1. 0 mg/L内添加低、中、高3个浓度水平,样品加标回收率为94. 9%～108. 0%,批内精密度和批间精密度分别为4. 6%～9. 8%(n=6)与4. 3%～8. 9%(n=6)。结论本方法简便快捷,分析时间短,灵敏度高,可用于职业接触苯人群尿中苯巯基尿酸的检测。

Objective A method based on diatomite bonded Fe_3 O4 magnetic nanocomposite（DBMNPs） as adsorbent was developed for the determination of S-phenylmercapturic acid（SPMA） in urine by dispersive solid-phase extraction and HPLC.Methods The urine sample was centrifugated,and the supernatant of urine samples（5. 0 ml） were collected for pH adjusting to 1. 0 by adding Hcl and extracted with DBMNPs. The extract was re-dissolved in methanol and then the analyte was separated on an EC-C18 column（150 mm × 4. 6 mm,4 μm） and detected by VWD. The S-phenylmercapturic acid was qualified by the retention time and quantified by standard curve method. Results The method showed good linearity in the range of0. 050 mg/L-1. 0 mg/L（r = 0. 999 7）. The detect limit of the method was 0. 028 mg/L（S/N = 3）. The average recovery ranged from 94. 9% to 108. 0% at three spiked levels in the range of 0. 050 mg/L-1. 0 mg/L. The intra-day and inter-day precisions（RSDs） were within 4. 6%-9. 8%（n = 6） and 4. 3%-8. 9%（n = 6）,respectively. Conclusion This method is simple,practical and high sensitive. It can be used to detect SPMA in urine for occupational population exposure to benzene.