Abstrato

Stability indicating spectrophotometric and TLC densitometric methods for the determination of gemifloxacin mesylate in tablet form

Bahia Abbas Moussa, Marianne Alphonse Mahrouse, Mahmoud Ali Hassan, Michael Gamal Fawzy

Gemifloxacin mesylate (GEM), a novel fluoroquinolone used for respiratory tract infections, was determined by three simple, accurate and precise spectrophotometric methods and a TLC densitometric method, in presence of its acid degradation product.Method (A) was first derivative technique (1D) which allows the determination of GEMbymeasuring the peak amplitudes at 280 and 360 nmwhere the acid degradation product displays zero value. Method (B) was based on second derivative ratio technique (2DD) in which the peak amplitude was measured at 289.3 nm using 10 ìg mL-1 of the acid degradation product as divisor. Method (C) depends on the formation of a colored product between GEM and pdimethylaminobenzaldhyde (DAB) reagent and the absorbance was measured at 400 nm. Method (D) depends on separation of GEMfrom its acid degradation product on TLC plates pre-sprayed with EDTA solution (3% w/v), using chloroform:methanol:ammonia solution (6:3:0.5, v/v/v) as developing system, followed by densitometric determination of GEM. The proposed methods were successfully applied to the analysis of GEM in pure and tablet forms, in addition to laboratory prepared mixtures (methodsA, B and D). The methods were validated in accordance to ICH guidelines and compared with the reference method, revealing non significant difference.