建立了高效准确分析饮用水中痕量抗生素的固相萃取/液相色谱串联质谱法分析供水厂中磺胺嘧啶、磺胺甲GFDA1唑、诺氟沙星、恩诺沙星、土霉素、头孢噻肟钠、罗红霉素7种抗生素残留的方法。通过优化固相萃取最终确定的样品前处理条件为：固相萃取小柱类型为Waters公司的Oasis HLB （500 mg，6 cc）；过样体积1 000 mL；上样流速10 mL/min；水样pH 4；洗脱剂类型为甲醇；洗脱剂用量9 mL。运用三重四级杆质谱检测器，在多反应选择监测离子模式（MRM）下进行目标物的分析检测，采用含0.1%甲酸的水作为流动相无机相A、乙腈作为流动相有机相B进行梯度洗脱。7种抗生素在0.5~200 ng/L的范围内有较好的线性关系，最低检出限为0.1~1.2 ng/L，平均加标回收率为68%~112%，相对标准偏差1.6%~10.7%。该方法的回收率和精密度良好，重现性佳且用时短，可满足实际水样中痕量抗生素的检测。

An efficient and accurate method for determination of antibiotic residues in drinking water is developed by solid phase extraction with high performance liquid chromatography tandem triple quadrupole mass spectrometry (HPLC-MS/MS).It is successfully applied to analyze sulfadiazine,sulfamethoxazole,norfloxacin,enrofloxacin,oxytetracycline,cefotaxime sodium,roxithromycin in the water supply plant in Suzhou.By optimizing the solid phase extraction methods,the sample pretreatment conditions are finally determined as follows:Oasis HLB (500 mg,6cc) extraction cartridge is found to deliver the best extraction efficiency for antibiotic residues in water.The pH value of water samples is adjusted to 4.The samples are loaded onto the cartridge at a flow rate of 10 mL·min^-1.The cartridges are rinsed with 9 mL of methanol to a 10 mL of centrifugal tube with cork.HPLC/MS² is operated on the multi reaction monitoring (MRM) mode to analyze the target antibiotics.Formic acid aqueous solution with a concentration of 0.1%(v∶v) and acetonitrile are used as the inorganic (A) and organic (B) mobile phases,respectively.By using this method,the calibration curves for seven kinds of antibiotic residues are linear in the range of 0.5-200 ng·L^-1,and the detection limits are in the range of 0.1-1.2 ng·L^-1,the average recovery rates in samples are in the range of 68%-112%,and RSD 1.6%-10.7%.

狄鑫(1993-),男,硕士生