超高效液相色谱-串联质谱法测定豆芽中恩诺沙星和环丙沙星

匀浆混匀的豆芽样品经磷酸盐缓冲溶液超声提取,提取液经HLB固相萃取小柱净化,甲醇洗脱。采用超高效液相色谱-串联质谱法测定恩诺沙星和环丙沙星的含量,以Agilent Eclipse Plus C18 RRHD色谱柱为固定相,以不同体积比的甲醇和0.1%(体积分数)甲酸-2mmol·L^-1乙酸铵溶液的混合液为流动相进行梯度洗脱,串联质谱分析中采用电喷雾正离子源和多反应监测模式。采用同位素内标法定量,恩诺沙星和环丙沙星的线性范围均为0.5~50.0μg·L^-1,检出限(3S/N)均为0.025μg·kg^-1。以空白样品为基体进行加标回收试验,所得回收率为89.2%~101%,测定值的相对标准偏差(n=6)为3.3%~9.2%。

UHPLC-MS/MS Determination of Enrofloxacin and Ciprofloxacin in Bean Sprouts

The bean sprout sample blended with homogenizer was extracted ultrasonically with phosphate buffer.The extract was purified with HLB solid phase extraction column,and then eluted with methanol.UHPLCMS/MS was applied to the determination of enrofloxacin and ciprofloxacin.Agilent Eclipse Plus C18 RRHD chromatographic column was used as stationary phase,and the mixture of methanol and 0.1%(φ)formic acid-2 mmol·L^-1 ammonium acetate solution mixed in different ratios was used as mobile phase in gradient elution.ESI+and multi-reactions monitor mode were adopted in MS/MS.Isotope was used as internal standard.Linearity ranges of enrofloxacin and ciprofloxacin were both found between 0.5μg·L^-1 and 50.0μg·L^-1,with detection limit(3 S/N)of 0.025μg·kg^-1.On the base of blank sample,test for recovery was made by standard addition method;values of recovery found were in the range of 89.2%-101%,with RSDs(n=6)of determined values in the range of 3.3%-9.2%.