超高效液相色谱-串联质谱法测定鸡蛋中氨苄西林及其代谢物残留

建立一种同时测定鸡蛋中氨苄西林及其主要代谢物氨苄西林酸和氨苄西林二酮哌嗪的超高效液相色谱串联质谱方法。样品经乙腈水溶液（70：30，V/V）提取、浓缩、SAX固相萃取小柱净化后，采用超高效液相色谱串联质谱法进行检测。结果显示，氨苄西林、氨苄西林酸和氨苄西林二酮哌嗪在1～200 ng/g的浓度范围内呈良好的线性关系。在鸡蛋中氨苄西林、氨苄西林酸和氨苄西林二酮哌嗪的检测限均为0.5 ng/g，定量限为1 ng/g。在1～100 ng/g添加浓度范围内，氨苄西林、氨苄西林酸和氨苄西林二酮哌嗪在鸡蛋中的平均回收率分别为84.0%～96.2%、85.6%～96.4%和89.2%～95.8%，批内、批间RSD均小于10%。添加不同浓度药物的鸡蛋样品具有良好的长期冷冻放置稳定性和反复冻融稳定性。蛋鸡在服用氨苄西林后，所产鸡蛋均能检出氨苄西林、氨苄西林酸和氨苄西林二酮哌嗪，且氨苄西林酸和氨苄西林二酮哌嗪的残留量和残留时间高于氨苄西林原型。上述内容表明，该方法各项技术指标均能满足残留检测要求，可用于定量测定鸡蛋中氨苄西林及其主要代谢物的残留量。

Determination of Ampicillin and Its Metabolites in Eggs by UPLC-MS/MS

A method of ultra high performance liquid chromatography tandem mass spectrometry was developed for the simultaneous determination of ampicillin and its main metabolites including ampicillin acid and ampicillin diketopiperazine in eggs.After extracted by acetonitrile: water (70：30，V/V) and concentrated by rotary evaporation, the sample solution was purified by SAX solid phase extraction column, and injected into the UPLC-MS/MS system to be tested. The results showed a good linear relationship between the range of 1 to 200 ng /g concentrations for ampicillin, ampicillin acid and ampicillin diketopiperazine.The detection and quantification limit of ampicillin and its metabolites in eggs were 0.5 ng/g and 1.0 ng/g, respectively. The recoveries of ampicillin and its metabolites were 84.0%～96.2%, 85.6%～96.4% and 89.2%~95.8%, and the coefficients of variation within and between the batches were less than 10% at the concentration range of 1.0 ng/g to 100.0 ng/g．In stability experiments, the results also showed low-temperature storage stability and freeze-thaw stability of the compounds in different concentrations in eggs.Ampicillin, ampicillin acid, and ampicillin diketopiperazine can be detectde in the eggs produced by laying hens afeter taking ampicillin, and the residual amount and residual time of ampicillin acid and ampicillin diketopiperazine are higher than ampicillin. The technical indicators of this method can meet the requirements of residue testing, which indicates the established method is suitable for the simultaneous determination of ampicillin and its metabolites in eggs.