液相色谱串联四极杆质谱法测定猪浓缩饲料中25-羟基维生素D3含量

Determination of 25-hydroxyvitamin D3 in pig concentrated feed by liquid chromatography-tandem mass spectrometry

目的建立液相色谱-串联四极杆质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)测定猪浓缩饲料中25-羟基维生素D3的分析方法。方法取适量猪浓缩饲料样品于离心管中,加水后置于振荡器上振荡破除环糊精包囊,再加入叔丁基甲醚振荡对目标物进行提取,在9000 r/min条件下离心5 min,氮气吹干后用2.00 mL流动相溶解,过滤膜后上机测定。实验使用反相色谱柱进行分离,流动相为甲醇(0.1%甲酸)和0.1%甲酸,采用梯度程序洗脱,三重四极杆质谱进行定量定性分析,采用内标法进行计算。结果该方法的检测限为5μg/kg,定量限为10μg/kg,在2~500μg/L范围内线性良好(r≥0.999),加标回收率在77.85%~90.22%之间,相对标准偏差(relative standard deviation,RSD)≤8.8%。结论本方法具有良好的准确度与精密度,具有较好的实用性和专属性。

Objective To establish a method for the determination of 25-hydroxyvitamin D3 in pig concentrated feed by liquid chromatography-tandem mass spectrometry(LC-MS/MS).Methods A suitable amount of pig feed sample was taken in the centrifugal tube.The water was chosen to get rid of cyclodextrin by oscillating,and the tert butyl methyl ether was chosen to extract 25-hydroxyvitamin D3 by oscillating.After 9000 r/min centrifugation for 5 min,nitrogen blowed to dry and dissolved in 2.00 mL mobile phase,then the solution was filtered by 0.22μm film and then injected.The targets were separated by the gradient elution with a reverse phase column as the stationary phase and 0.1%formic acid with methanol as the mobile phase.The qualification and quantification were achieved by a tandem mass spectrometry and internal standard method was used for calculation.Results The results showed that the limit of detection(LOD)was 5μg/kg,limits of quantification(LOQ)was 10μg/kg.The linearity of the method was good in the range of 2~500μg/L and the liner correlations were all above 0.999,the recovery rate was between 77.85%~90.22%,and the RSD(relative standard deviation)was lower than 8.8%.Conclusion This method has good accuracy and precision,and has good practicability and specificity.