Application of Videodensitometric and Classical Densitometric HPTLC for Quantification of Fluoroquinolone Derivatives in Pure and Tablet Forms

摘要

A new,simple,and rapid high-performance thin layer chromato-graphic method coupled with densitometry has been developed and validated for the determination of enoxacin, ofloxacin, and pefloxacin in tablets. HPTLC analysis was performed on silica gel 60F_(254) plates in horizontal chambers with dichloromethane-methanol-25% NH_3, 7 + 5 + 1.5, as mobile phase. Detection and quantification were performed by videodensitometry at A = 254 nm and by classical densitometry at the wavelength of maximum absorption of the drugs determined. The active substances were extracted from tablets with a 0.05% solution of ammonia in methanol (enoxacin, ofloxacin) or with methanol (pefloxacin). Calibration plots were constructed in the range 0.1 to 0.6 mug muL_(-1) and were linear for all analytes with good correlation coefficients (r from 0.992 to 0.9998). The precision of the proposed chromato-graphic methods, expressed as RSD, were between 7.56 and 10.08. The mean recoveries of the three antibiotics from tablets ranged from 97.46 to 102.87%.