Lovdahl M, Steury J, Russlie H, Canafax D M
College of Pharmacy, Department of Pharmacy Practice, University of Minnesota, Minneapolis 55455.
J Chromatogr. 1993 Aug 11;617(2):329-33. doi: 10.1016/0378-4347(93)80508-2.
An isocratic high-performance liquid chromatographic method has been developed to determine ciprofloxacin levels in chinchilla plasma and middle ear fluid. Ciprofloxacin and the internal standard, difloxacin, were separated on a Keystone ODS column (100 x 2.1 mm I.D., 5 microns Hypersil) using a mobile phase of 30 mM phosphate buffer (pH 3), 20 mM triethylamine, 20 mM sodium dodecyl sulphate-acetonitrile (60:40, v/v). The retention times were 3.0 min for ciprofloxacin and 5.2 min for difloxacin. This fast, efficient protein precipitation procedure together with fluorescence detection allows a quantification limit of 25 ng/ml with a 50 microliters sample size. The detection limit is 5 ng/ml with a signal-to-noise ratio of 5:1. Recoveries (mean +/- S.D., n = 5) at 100 ng/ml in plasma and middle ear fluid were 89.4 +/- 1.2% and 91.4 +/- 1.6%, respectively. The method was evaluated with biological samples taken from chinchillas with middle ear infections after administering ciprofloxacin.
已开发出一种等度高效液相色谱法，用于测定龙猫血浆和中耳液中环丙沙星的含量。环丙沙星和内标二氟沙星在Keystone ODS柱（内径100×2.1 mm，5微米Hypersil）上分离，流动相为30 mM磷酸盐缓冲液（pH 3）、20 mM三乙胺、20 mM十二烷基硫酸钠-乙腈（60:40，v/v）。环丙沙星的保留时间为3.0分钟，二氟沙星的保留时间为5.2分钟。这种快速、高效的蛋白沉淀方法结合荧光检测，使用50微升的样品量时，定量限为25 ng/ml。检测限为5 ng/ml，信噪比为5:1。血浆和中耳液中100 ng/ml的回收率（平均值±标准差，n = 5）分别为89.4±1.2%和91.4±1.6%。在用环丙沙星治疗后，从患有中耳感染的龙猫身上采集的生物样品对该方法进行了评估。
