An improved HPLC assay for ciprofloxacin in biological samples
Pei, Y.Y.; Meng, X.; Nightingale, C.H.
Zhongguo Yao Li Xue Bao 15(3): 197-201
1994
ISSN/ISBN: 0253-9756 PMID: 7976369 Document Number: 429507
A simple and sensitive high performance liquid chromatographic method was developed for determination of ciprofloxacin (Cip) in 0.1 ml of rabbit and human serum and CSF. Separation of Cip and pipemidic acid (internal standard) was achieved on Nucleosil C-18 (4.6 mm times 250 mm) using fluorescence detection with lambda-exc 274 nm and lambda-emi 418 nm. The mobile phase was composed of acetonitrile and phosphate buffer 10 mmol cntdot L-1 (pH 2.7) containing tetrabutylammonium hydrogen sulfate 5 mmol cntdot L-1 (18:82, vol:vol) and the flow rate was set at 1.0 ml cntdot min-1. The retention times were 5.9 min for Cip and 4.0 min for pipemidic acid. The inter-day coefficient of variation was lt 6.97% (n = 5) and the intra-day coefficient of variation was lt 3.33% (n = 5). The limits of detection were 3 ng cntdot ml-1 serum and 5 ng cntdot ml-1 CSF, (r gtoreq 0.9996). Application of this method was demonstrated with simultaneous measurements of concentration-time profiles of Cip in rabbit serum and CSF during iv infusions at constant rates of 0.33, 1.0, and 2.5 mg cntdot kg-1 cntdot h-1.