土壤中磺胺类抗生素的检测方法优化及残留、降解研究

优化了磺胺甲基嘧啶(SM1)、磺胺二甲嘧啶(SM2)、磺胺对甲氧嘧啶(SMT)、磺胺甲噁唑(SMZ)4种磺胺类抗生素的高效液相色谱(H PLC)检测方法,分析了广州市养殖场周边土壤中磺胺类抗生素的残留特征,并进行了2种磺胺类抗生素的土壤降解试验。结果表明,4种磺胺类抗生素分别在0.10~10μg ml-1范围内线性良好,相关系数R>0.99。确定了最佳提取液为甲醇:含EDTA的Mcllvain缓冲液=1∶1(V/V),4种磺胺类药物的检测限与回收率分别为2.9~4.7μg kg-1、83.6%～90.1%。广州市18个规模化养殖场周边土壤中磺胺类抗生素污染以SM2为主,含量为1.75μgkg-1,其它3种均未被检出。土壤中磺胺类抗生素的含量总体呈随培养时间而不断下降的趋势,SMZ的降解速率大于SM2。

Method Optimization for Determination of Sulfonamides and Their Residual and Degradation in Soils

In this article,the determination of sulfamerazine(SM1),sulfamethazine(SM2),sulfameter(SMT),sulfamethoxazole(SMZ) by high performance liquid chromatography(HPLC) were improved and optimized,the residual characteristics of sulfonamides antibiotics in guangzhou farms surrounding soil were analyzed,and the degradation of two kinds of sulfonamide antibiotics in soils was tested.The results showed that the regression of calibration curves fitted well with correlation coefficient higher than 0.99 in the concentration range of 0.1-10 μg ml-1 of four sulfonamide antibiotics.The optimum extracting solution was methanol: the buffer of mcllvain containing EDTA=1:1(V/V),the detection limit and recoveries of four sulfonamides were 2.9-4.7 μg kg-1 and 83.6%-90.1%.The soil sulfonamide antibiotics pollution in 18 large-scale farms of Guangzhou was primarily derived from SM2,and its concentration was 1.75 μg kg-1,while the other three antibiotics were not detected.The concentrations of sulfonamide antibiotics generally had a declining trend with the incubation time in soil,and the degradation rate of SM2 was faster than SMZ.