柱切换直接进样高效液相色谱法测定蜂蜜中3种抗生素的残留量

Direct Injection Determination of Oxytetracycline, Tetracycline andChlortetracycline in Honey by the High Performance LiquidChromatography with Column Switching Technique

建立了柱切换反相高效液相色谱法直接进样分离、测定蜂蜜中3种四环素族抗生素(土霉素OTC、四环素TC、金霉素CTC)残留量的分析方法.方法包括:用缓冲溶液溶解样品、直接进样、二次蒸馏水作流动相在C18预柱上在线富集和净化,然后用柱切换阀将预柱与一个C18分析柱接通,草酸溶液-乙腈-甲醇作流动相、紫外检测器在350 nm处检测.各组分回收率均大于85%;相对标准偏差小于10%;标准曲线的相关系数在0.9983～0.9991之间;最低检出浓度(≤0.02 mg/kg),满足欧盟和日本等国要求(0.05mg/kg).

A direct injection method for isolation and determination of tetracyclines, which includes oxytetracycline (OTC), tetracycline (TC), and chlortetracycline (CTC) in honey by a high performance liquid chromatographic column switching system is presented. The tetrcyclines were extracted into a buffer solution, a C-18 pre-column with. redistilled water as mobile phase was used as the first column, to provide for the sample enrichment and cleanup online, then a C-18 chromatographic column with oxalic acid solution-acetonitrile-methanol as mobile phase for analysis was used as the second column which was coupled on-line to the first one with a switching valve, ultra violet detection is employed at 350 ran. Recoveries exceeded 85% for all tetracyclines at all levels, with good precision. Correlation coefficients of standards curves for TC, OTC and CTC ranged from 0. 9983 to 0. 9991. The limits of detection of the method were all below 0. 02 mg/kg, and adequate to meet the needs of regulatory agencies such as European Community and Japan (0. 05 mg/kg). The procedure is rapid, precise, and requires minimal preparation and organic solvents, it can be applied to routine surveillance programs.