SPE-HPLC法检测早胜牛肉中土霉素、四环素和金霉素的残留

Residues determination of oxytetracycline,tetrarcycline and chlortetracycline in Zaosheng cattle meat by SPE-HPLC

目的建立同时测定早胜牛肉中残留的土霉素、四环素和金霉素固相萃取-高效液相色谱方法。方法以Na2EDTA-Mcllvaine缓冲溶液（p H4.0）为样品提取液,15%三氯乙酸为蛋白沉淀剂,固相萃取柱净化富集目标物,草酸0.01mol/L/乙腈/甲醇溶液为流动相,紫外检测器350 nm处检测,外标法进行定量。结果在优化前处理和分析条件下,3种抗生素在质量浓度范围内线性关系良好,相关系数r2〉0.998,土霉素、四环素、金霉素的检出限分别为18、15和30μg/kg,样品加标平均回收率为76.10%~95.22%,相对标准偏差〈10%。结论方法的灵敏度和精密度较高,且重复性好,适用于牛肉样品中土霉素、四环素和金霉素残留的检测。

Objective To establish a method for simultaneous determination of 3 tetracyline antibiotics（TCs）oxytetra-cycline（OTC）,tetracycline（TC）,chlorotetecycline（CTC））residues in Zaosheng cattle meat using solid phase extraction-high performance liquid chromatography（SPE-HPLC）. Methods The samples were extracted by Na2EDTA-Mcllvaine buffer solution（p H=4.0）,and 15% trichloroacetic acid（TCA）as the protein precipitation solution,then the targets were cleaned up and enriched by C18 solid phase extraction column. HPLC Mobile phase consisted of oxalic acid（0.01mol/L）,acetonitrile as well as methanol. The detection wavelength was 350 nm and external standard method was adopted for quantification. Results The calibration curves of 3 TCs had good linearity with correlation coefficients of 0.998. The limits of detection of OTC,TC and CTC were 18、15、30 μg/kg,respectively,while their average recoveries were 76.10%-95.22%,with relative standard deviations（RSD）lower than 10% after optimized pretreatment and analytical conditions. Conclusion The method has high sensitivity,precision,and good repeatability,and can meet the needs of residue determination of TCs in meat.