高效液相色谱-串联质谱法对水环境中微量磺胺、大环内酯类抗生素、甲氧苄胺嘧啶与氯霉素的检测

Simultaneous Determination of Trace Sulfonamides,Macrolides,Trimethoprim and Chloramphenicol in Aquatic Environment Using Liquid Chromatography-Tandem Mass Spectrometry

应用固相萃取（SPE）及液相色谱-电喷雾串联质谱（LC—ESIMS／MS）技术，建立了水体中微量磺胺、大环内酯类抗生素、甲氧苄胺嘧啶及氯霉素的定量分析方法。水样中的抗生素通过HLB萃取小柱富集后，以C18反相柱为分析柱，甲醇、醋酸铵和0．1％甲酸混合溶液为流动相，采用LC—MS／MS进行定量分析。选择电喷雾正电离源（ESI＋），多反应监测模式（MRM），内标法定量。海水和城市污水中抗生素的方法定量下限分别为1，1～34．7ng／L和2．5～57．2ng／L，平均回收率分别为78％～98％、67％～111％，相对标准偏差不高于8．8％。通过该方法初步分析了海水及污水中抗生素的含量，检出多种磺胺和大环内酯类抗生素。

A reliable, sensitive and selective method has been developed for multi-residue determination of sulfonamides, maerolides, trimethoprim and chloramphenicol in aqueous environment by using solid phase extraction（SPE） coupled to liquid chromatography- tandem mass spectrometry（LC - MS/MS） with electrospray ionization operated in positive mode （ESI ＋ ）. HLB （hydrophile-lipophile balance） cartridges were used to enrich and purify the antibiotics in water. A reverse phase（RP-C18） column was applied for separation of the investigated antibiotics. Methanol and 5 mmol/L ammonium acetate-0. 1% formic acid were used as the mobile phases. The antibiotics were quantified under multiple reaction monitoring （MRM） mode by internal standard method. The linear range were obtained from 1 μg/L to 2 000 μg/L. The method quantification limits （MQLs） for the analytes were 1.1 -34.7 ng/L and 2.5 -57.2 ng/L in sea water and wastewater, respectively. The recoveries of the antibiotics were in the range of 78% -98% for sea water and 67% - 111% for wastewater, with relative standard deviations（RSDs） no more than 8.8% . The method was applied to analyze the antibiotic residues in sea water and wastewater collected from the Pearl River Delta. The result indicated that several sulfonamides and macrolides, including sulfamethoxazole （SMX） , trimethoprim （TMP） and dehydroerythromycin（ETM -H2O） were detected at nanograms per liter in sea water. While in wastewater samples, SMX, sulfamethazine（SMZ）, TMP, ETM-H2O, and roxithromycin（RTM） were detected at 29.2 -468.2 ng/L.