Derivative spectrophotometric analysis of 4-quinolone antibacterials in formulations and spiked biological fluids by their Cu(II) complexes

A derivative UV-spectrophotometric analytical procedure was developed for d etermination of three 4-quinolone antibacterials: norfloxacin (NFX), ciprof loxacin (CFX), and sparfloxacin (SFX), The method depends on the complexati on of Cu(II) with the studied compounds in aqueous medium. A third order, m easurement was applied for their quantification, A linear correlation was e stablished between the amplitude of the peak and concentration for all the studied drugs in the range of 15-80, 35-120, and 200-700 ng/mL, with minimu m detectability (S/N = 2) of 1,0, 1,3, and 5.1 ng/mL for NFX, CFX, and SFX, respectively, The method was successfully applied for accurate, sensitive, and selective determination of the studied drugs in bulk and tablets formu lation with average percentage recoveries of 99.22 +/- 0.55 to 100.33 +/- 1 .60. The results obtained were favorably compared with those of the referen ce method, The method was also used to determine sparfloxacin in spiked hum an plasma and urine. The results obtained were satisfactory, accurate, and precise.