Abstract

Spectrophotometric methods for the determination of gemifloxacin mesylate in pure form and pharmaceutical formulations

Author(s): Zakaria Y.Al Shoaibi, Ayman A.Gouda

Three accurate, simple and precise spectrophotometric methods for the determination of gemifloxacinmesylate (GMX) in pure formand tablets are developed. The first method is based on the reaction of ninhydrine reagent with primary amines present in gemifloxacin in N, NÂ’-dimethylformamide medium (DMF) producing a colored product which absorbs maximally at 590 nm. The second method is based on the reaction of drug with ascorbic acid inDMFmediumresulting in the formation of a colored product, which absorbs maximally at 530 nm. The third method is based on the reaction of gemifloxacin with p-benzoquinone (PBQ) to form a colored product with ëmaxat 400 nm. BeerÂ’s law is obeyed in the concentration ranges 4.0-32, 8.0- 40 and 9.0–72 ìg mL-1 and molar absorptivity of 9.68 × 103, 5.58 × 103 and 4.98 × 103 l mol-1 cm-1 for ninhydrin, ascorbic acid and PBQ, respectively. The optimumexperimental parameters for the reactions have been studied. The validity of the described procedures was assessed. The proposed methods could be used for the determination of gemifloxacin in pharmaceutical formulations. No interference was observed from common pharmaceutical adjuvants. Statistical comparison of the results with the reference method shows excellent agreement and indicates no significant difference in accuracy and precision. The procedures were rapid, simple and suitable for quality control application.