高效液相色谱-电喷雾串联质谱法测定蜂蜜中5种头孢菌素

Determination of 5 Cephalothins in Honey by High Performance Liquid Chromatography Coupled with Electrospray Tandem Mass Spectrometry

建立了用高效液相色谱-电喷雾串联质谱(LC-MS-MS)测定蜂蜜中5种头孢菌素残留量的方法。蜂蜜样品用磷酸盐缓冲溶液溶解,经OasisHLB固相萃取柱净化。5种头孢菌素在C18柱上以乙腈-水为流动相梯度洗脱条件下完成分离,电喷雾电离串联质谱在正离子多反应监测模式下进行测定。添加浓度在2～100μg/kg范围时,回收率为84.2%～103.6%;相对标准偏差为3.89%～9.08%。本方法头孢唑啉的定量限为10μg/kg,头孢匹林、头孢氨苄、头孢洛宁、头孢喹肟的定量限为2.0μg/kg。

A sensitive method was developed for the determination of residue of 5 cephalothins in honey by high performance liquid chromatography coupled with electrospray tandem mass spectrometry （HPLC-MS/MS）. Honey sample was dissolved in sodium dihydrogen phosphate buffer solution, then sample solution was cleaned up with Oasis HLB SPE cartridge. Identification was achieved by electrospray ionization（ESI） in positive mode. The target compounds were separated on a C18 column by gradient elution with acetonitrile and 0.1% formic acid solution as mobile phase and residues were quantified in multiple reaction monitoring mode. Recoveries of 5 cephalothins were between 84.2% and 102.5%（n=10） at spiked levels of 2.0-100.0 μg/kg. The relative standard deviations（RSD） of the method were between 3.89% and 9.08%. The limit of quantitation（LOQ） of the method for cefazolin was 10.0 μg/kg, and the LOQ of the method for cephapirin, cephalexin, cefalonium and cefquinome was 2.0 μg/kg.