simple high-performance liquid chromatographic method for determination of ciprofloxacin in human plasma

a rapid, simple and sensitive high-performance liquid chromatography method was developed for determination of ciprofloxacin in plasma by means of ultraviolet detection. ofloxacin was used as an internal standard and separation carried on a novapak c18 column using a mobile phase of 0.01 m phosphate buffer (ph =2.6): methanol (82: 18 v/v). extraction of drug was performed from plasma by liquid-liquid extraction and the average recovery was 78.2% the assay is precise, with inter-assay coefficient of variation of 6.70 % at 0.25-8 mg/ml (n=3). using uv detection at 277 nm the detection limit for ciprofloxacin was 20 ng/ml of plasma and the mean extraction recovery was 78.2 %. short elution time, using uv detector and usage of ofloxacin as internal standard are advantages of this method