液相色谱-串联质谱同时测定禽肉组织中盐酸金刚烷胺、盐酸金刚乙胺、地塞米松、替米考星及喹乙醇代谢物的残留量

建立了同时测定禽肉组织中盐酸金刚烷胺、盐酸金刚乙胺、地塞米松、替米考星及喹乙醇代谢物残留量的液相色谱-串联质谱分析方法。样品用2 mol/L氢氧化钠溶液水解,盐酸调节p H值后,以乙腈作为提取溶剂,经C18固相萃取柱净化。各待测物分别经0.1%甲酸甲醇溶液和氨化甲醇(0.1%氨水)洗脱,Phenomenex Kinetex C18(100 mm×4.6 mm,2.6μm)色谱柱进行分离,采用0.1%甲酸(含5 mmol/L乙酸铵)-甲醇作流动相,梯度洗脱,串联质谱法对5种药物含量进行测定。结果表明,5种药物在2~100μg/L范围内线性关系良好,相关系数为0.996 2~0.999 8。在加标浓度为5~50μg/kg的禽肉组织中,这5种药物的加标回收率为73.7%~92.3%,相对标准偏差(n=5)为3.9%~16.6%,检出限为0.2~3.0μg/kg,定量下限为0.7~10μg/kg。方法快速、简便、经济实用,符合法规要求,可满足日常检测的需要。     

Determination of antibacterial agent tilmicosin in pig plasma by LC/MS/MS and its application to pharmacokinetics

A rapid and sensitive high‐performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed and validated to quantify tilmicosin in pig plasma. Plasma samples were prepared by liquid–liquid extraction. Chromatographic separation was achieved on a C₁₈ column (2.1 × 30 mm, 3.5 μm) using acetonitrile–water (90:10, v /v; water included 0.1% formic acid) as the mobile phase. Mass detection was carried out using positive electrospray ionization in multiple reaction monitoring mode. The calibration curve was linear from 0.5 to 2000 ng/mL (r ² = 0.9998). The intra‐ and inter‐day accuracy and precision were within the acceptable limits of ±10% for all tilmicosin concentrations. The recoveries ranged from 95 to 99% for the three tested concentrations. The LC–MS/MS method described herein was simple, fast and less laborious than other methods, achieved high sensitivity using a small sample volume, and was successfully applied to pharmacokinetic studies of tilmicosin enteric granules after oral delivery to pigs. In comparison with tilmicosin premix, tilmicosin enteric granules slowed the elimination rate of tilmicosin, prolonged its period of action and significantly improved its bioavailability.     

水产品中螺旋霉素、替米考星、泰乐菌素与北里霉素残留量的超高效液相色谱-紫外检测法同时测定

建立了水产品肌肉组织中螺旋霉素、替米考星、泰乐菌素、北里霉素同时测定的超高效液相色谱-紫外检测(UPLC-TUV)方法。样品经乙腈提取后,浓缩至近干,用4%NaCl溶解残渣,正己烷除脂,经固相萃取小柱净化,乙腈洗脱;以乙腈-25 mmol/L磷酸二氢铵(pH2.5,含10%乙腈)为流动相,以ACQUITYUPLC BEHC18为分离柱,柱温为45℃,流速为0.3 mL/min,紫外检测。方法在0.100~20.0 mg/L范围内呈线性相关,螺旋霉素、替米考星、泰乐菌素和北里霉素的相关系数分别为0.998 7、0.999 3、0.999 4和0.998 0。平均回收率为70%~102%,相对标准偏差为2.9%~11.2%,螺旋霉素、替米考星、泰乐菌素和北里霉素的检出限分别为25、25、50、75μg/kg。方法满足水产品肌肉组织中螺旋霉素、替米考星、泰乐菌素和北里霉素的残留量测定。