Studies on cinoxacin

Abstract

A spectrophotofluorimetric method for the determination of cinoxacin was evaluated. An almost linear relation was found between fluorescence and concentration of cinoxacin extracted from urine (r = 0.98), serum (r = 0.96), and renal and prostatic tissue homogenates (r = 0.94; r = 0.99). The minimal sensitivity of the spectrophotofluorimetric method was 0.10 μg/ml when testing urine and serum. The corresponding figures for prostatic and renal tissue were 0.05 μg/mg and 0.10 μg/mg wet weight. The results of the determinations of cinoxacin concentrations in urine obtained by this method were compared with those found by means of an agar-well diffusion bioassay. A good correlation was found between the results obtained by the two methods. It is concluded that the spectrophotofluorimetric method is suitable for determination of the cinoxacin concentrations in body fluids and tissues obtained during maintenance treatment in man.