固相萃取-高效液相色谱法同时测定牛奶中22种磺胺类兽药残留

建立了一种基于固相萃取技术同时测定牛奶中22种磺胺类兽药残留的高效液相色谱分析方法.样品经乙腈-甲酸混合溶液提取,乙腈饱和的正己烷除酯后,HLB固相萃取柱净化,以甲醇-2 mmol/L乙酸铵(含0.2％乙酸)为流动相进行梯度洗脱,XBridge C18色谱柱进行分离,采用光电二极管阵列检测器检测,外标法定量.磺胺类化合...

Determination of 22 sulfonamides residues in milk by high performance liquid chromatography coupled with solid phase extraction

A method of simultaneous determination of 22 sulfonamides residues in milk was established by coupling high performance liquid chromatography(HPLC)with solid phase extraction.The milk sample was extracted with acetonitrile-formic acid,degreased with n-hexane,and purified by a HLB solid-phase extraction cartridge.An Xbridge C18 chromatographic column was used to complete the separation of the target compound under gradient elution mode with methonal-2 mmol/L ammonium acetate(containing 0.2%acetate acid)as the mobile phase.The analytes were detected with a diode-array detector and quantified by external standard method.The method developed in this study showed that all the sulfonamides were determined with an excellent linear relationship during the concentration of 50-1000 ng/mL with correlation coefficients(R2)greater than or equal to 0.999.The limits of detection(LOD)of all sulfonamides were 10μg/kg and the limits of quantitation(LOQ)for all sulfonamides were 4μg/kg.The spiked recoveries of the analytes from blank milk samples at three levels of 10,50 and 100μg/kg ranged from 86.7%to 98.2%with the relative standard deviations(RSDs)of 1.6%-8.4%.The method could be used for simultaneous determination of multiple sulfonamides residues.