Application of videodensitometric and classical densitometric HPTLC for quantification of fluoroquinolone derivatives in pure and tablet forms

Abstract

A new, simple, and rapid high-performance thin layer chromatographic 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 λ = 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 μg μL −1 and were linear for all analytes with good correlation coefficients ( r from 0.992 to 0.9998). The precision of the proposed chromatographic methods, expressed as RSD , were between 7.56 and 10.08. The mean recoveries of the three antibiotics from tablets ranged from 97...