采用LC/MS~n法分析恩诺沙星在锯缘青蟹血浆中的代谢产物

采用电喷雾离子阱质谱法在正离子检测方式下,对锯缘青蟹口灌恩诺沙星给药后血淋巴中恩诺沙星和代谢产物进行定性分析。通过对血浆中恩诺沙星及其代谢产物的质谱裂解行为进行碰撞诱导解离分析,获得了各化合物的多级质谱信息,通过比较各化合物结构和质谱裂解途径的异同点,发现有三个代谢产物,其中峰面积最大的为环丙沙星,其次为羟基化恩诺沙星,另一代谢产物可能是加氧恩诺沙星;推测恩诺沙星在锯缘青蟹体内的代谢反应主要是脱乙基反应、羟基化反应和氧化反应。通过定量分析,血浆中恩诺沙星和代谢产物环丙沙星的浓度分别为19.1μg/ml和0.526μg/ml。

Analysis on the metabolites of enrofloxacin in the hemolymph of mud crab (Scylla serrata) by means of LC/MSn

The enrofloxacin and its metabolites in the hemolymph of mud crab,Scylla serrata,following oral administration were analyzed using positive ion electrospray ion trap mass spectrometry in a multi-stage MS full scan mode.The samples were infused into the ion source with a syringe pump.The multi-stage mass spectral information was obtained following the mass spectrometric analysis of enrofloxacin and its metabolites by collision induced dissociation.The result showed that enrofloxacin was biotransformed to three metabolites in the hemolymph,which the peak area of ciprofloxacin was the biggest among three metabolites,the second was hydroxylate enrofloxacin,and the third was oxide enrofloxacin.The quantitative analysis revealed that the concentrations of enrofloxacin and its metabolite ciprofloxacin were 19.1 μg/ml and 0.526 μg/ml,respectively.