Determination of ciprofloxacin in plasma and urine by HPLC with ultraviolet detection.

A simple, sensitive isocratic method for the detection and quantification of ciprofloxacin in plasma and urine has been developed. The assay consisted of reversed-phase HPLC with ultraviolet detection. Plasma proteins were removed by a fast and efficient procedure. For the urine samples, the only required sample preparation was dilution. Separation was achieved on a C18 reversed-phase column. The quantification limit was 0.01 mg/L in plasma and 0.5 mg/L in urine. This method was sufficiently sensitive for pharmacokinetic studies.