Krol G J, Beck G W, Benham T
Clinical Pharmacology, Bayer Corporation, West Haven, CT 06516-4174, USA.
J Pharm Biomed Anal. 1995 Dec;14(1-2):181-90. doi: 10.1016/0731-7085(95)01611-2.
An improved high-performance liquid chromatography (HPLC) procedure for the analysis of ciprofloxacin and three of its metabolites in plasma, serum and urine samples was developed. The previously published HPLC procedure described the isocratic separation of ciprofloxacin and three ciprofloxacin metabolites in urine samples on a polystyrene-divinylbenzene reverse-phase column followed by quantitation using a UV detector. The present procedure involved the same chromatographic separation, but is also applicable to the analysis of plasma and serum as well as urine samples, and quantitation was based on fluorometric detection after postcolumn induction of fluorescence instead of UV detection. The post-column induction of fluorescence was necessary because the M2 and M3 metabolites of ciprofloxacin have relatively weak native fluorescence, and induction enhanced the fluorometric signals of metabolites M2 and M3 forty-four-fold and eleven-fold, respectively. The observed enhancement of fluorescence may be attributed to the partial conversion by UV light of metabolites M2 and M3 to metabolite M1 which has intense native fluorescence. The lower quantitation limits of ciprofloxacin and metabolites M1, M2 and M3 were 0.05 micrograms ml-1, 0.01 micrograms ml-1, 0.05 micrograms ml-1, and 0.5 micrograms ml-1, respectively. All four analytes were quantitated using one isocratic elution of either plasma or serum supernatant after the precipitation of proteins or the isocratic chromatography of diluted urine samples.
开发了一种改进的高效液相色谱（HPLC）方法，用于分析血浆、血清和尿液样本中的环丙沙星及其三种代谢物。先前发表的HPLC方法描述了在聚苯乙烯-二乙烯基苯反相柱上对尿液样本中环丙沙星和三种环丙沙星代谢物进行等度分离，然后使用紫外检测器进行定量。本方法采用相同的色谱分离，但也适用于血浆、血清以及尿液样本的分析，并且定量基于柱后诱导荧光后的荧光检测而非紫外检测。柱后诱导荧光是必要的，因为环丙沙星的M2和M3代谢物具有相对较弱的天然荧光，诱导分别增强了代谢物M2和M3的荧光信号44倍和11倍。观察到的荧光增强可能归因于紫外光将代谢物M2和M3部分转化为具有强烈天然荧光的代谢物M1。环丙沙星以及代谢物M1、M2和M3的较低定量限分别为0.05微克/毫升、0.01微克/毫升、0.05微克/毫升和0.5微克/毫升。在蛋白质沉淀后，使用血浆或血清上清液的一次等度洗脱对所有四种分析物进行定量，或者对稀释的尿液样本进行等度色谱分析。
