RP-HPLC快速检测牛奶中7中四环素类药物残留量的研究

目的：建立快速检测牛奶中7 种四环素类药物残留的反相高效液相色谱法。方法：用0.1mol/L McIlvaine-EDTA 溶液和50% 三氯乙酸(TCA)溶液共同处理牛奶样品，通过Waters Oasis HLB 固相萃取柱进行净化处理。仪器条件中所用色谱柱为SunfireTM C18(250mm × 4.6mm，5μm)柱，以甲醇- 乙腈-0.01mol/L 草酸(pH2)为流动相，采用梯度洗脱模式。结果：7 种四环素类药物线性范围宽，峰面积和样品浓度在0.05～1μg/ml 范围内呈很好的线性关系，加标平均回收率为78.66%～106%，最低检测限为0.02μg/ml。结论：该方法操作简单、重现性好、检测限低、灵敏可靠，可在14min 内同时将四环素等7 种四环素类药物达到基线分离。

Reversed Phase High Performance Liquid Chromatographic Determination of 7 Tetracyclines Residues in Bovine Milk

Residues of 7 tetracyclines were extracted with 0.1mol/L EDTA-McIlvaine buffer solution (pH 3.8) from bovine milk, pretreated with 50% trichloroacetic acid solution, and then subjected to cleanup with HLB solid phase extraction (SPE) cartridge. The analysis of 7 tetracyclines residues was conducted by reverse phase high-performance liquid chromatograph on a sunfireTM C18 column (250 mm × 4.6 mm, 5 μm i.d) with methanol - acetonitrile - 0.01 mol/L oxalic acid solution as a mobile phase (gradient elution) at the flow rate of 1.0 ml/min. The results showed that the method presented a wide-range high-linearity for analyzing these tetracyclines. The peak area was positively correlated with sample solution concentration in the range of 0.05 － 1.0 μg/ml. The average recovery was 78.66% － 106% and the lowest detection limit was 0.02 μg/ml. The method is sensitive, reliable and easy-operating, and can be used for simultaneous determination of 7 tetracyclines residues in bovine milk within 14 minutes.