应用柱后衍生荧光测定法检测牛奶和猪肉中土霉素和四环素残留量

Applying Post-column Eerivative Fluorescent Method for Analyzing Oxytetracycline and Tetracycline Residues in Milk and Pork

目的 建立动物性食品中土霉素和四环素残留的高效液相荧光检测方法。方法 样品经含乙二胺四乙酸二钠的丁二酸钠缓冲液除蛋白后 ,由SPE C1 8小柱提纯净化 ,ODS C1 8柱分离 ,8%氧氯化锆溶液柱后衍生化 ,在激发波长 (Ex) 40 6nm和发射波长 (Em) 5 15nm处检测土霉素和四环素与锆离子的螯合物含量。结果 实验优化了锆试剂的浓度和柱后衍生的条件 ,土霉素和四环素的回收率分别为 89 5 9%和 92 5 9% ,变异系数 (CV)分别为 4 98%和 6 74%。最低检出浓度 (信噪比 5∶1)分别为 3ug L和 5ug L ,线性范围为 10ug L～ 10mg L ,相关系数分别为 0 9999和 1 0 0 0 0。结论 本方法能够稳定、快速、灵敏地检测动物性食品中土霉素和四环素残留量。

Objective To develop a method measuring the level of Oxytetracycline (OTC) and Tetracycline (TC) residues in animal-source foods by High-performance Liquid Chromatography (HPLC). Methods The samples were eluted by SPE-C18 column and separated by ODS-C18 column after removing protein with sodium succinate buffer including EDTA-Na2, using post-column derivation with 8% zirconyl chloride octahydrate. The zirconium chelate was detected at excitation bandwidth of 406 nm and emission bandwidth of 515 nm. Results This method could optimize the concentration of zirconium reagent and the condition of post-column derivation. The recovery rates of OTC and TC were 89.59% and 92.59%; the coefficients of variation (CV) were 4.98% and 6.74%, respectively. The detection sensitivity of this assay (signal-to-noise=5∶1) were 3μg/L and 5μg/L respectively. The fluorescence intensity with the content of zirconium chelate was linear in a concentration range of 0.01～10μg/L with the correlation coefficient 0.9999 and 1.0000, respectively.Conclusions The method can be applied in analyzing OTC and TC residues in animal-source foods stably, quickly and sensitively.