title: Ion-pair spectrophotometric estimation of gemifloxacin.
abstract: BACKGROUND
  The main objective was to develop and validate a simple, accurate, precise, and sensitive ion-pair spectrophotometric extraction method for the assay of gemifloxacin mesylate (GFX) in pure, tablets and spiked human urine.
  
  
  METHODS
  The method is based upon the reaction of gemifloxacin with methyl orange, forming a yellow-colored complex in acidic medium, which is extracted in chloroform and analyzed. The extracted complexes showed absorbance maxima (λmax) found to be at 427 nm.
  
  
  RESULTS
  Beer's law was obeyed for a wide concentration range, i.e., 10-80 μg/ mL as the extracted species seemed well defined and stable. The surface or an interphase adsorption phenomenon was not a problem. Optimization of the reaction was carried out with factors such as buffer strength, stability of complex, and molar ratio of drug: Dye and extraction time. The proposed method was validated as per the ICH guidelines. The recovery studies confirmed the accuracy and precision of the method.
  
  
  CONCLUSIONS
  The above-mentioned method was a rapid tool for routine analysis of GFX in the bulk and pharmaceutical dosage forms.
authors.affiliation: Dadhichi College of Pharmacy, Cuttack, Odisha, India.
authors.forename: Satyabrata
authors.initials: S
authors.lastname: Sahu
authors.forename: Saroj Kumar
authors.initials: SK
authors.lastname: Patro
authors.forename: Una Laxmi
authors.initials: UL
authors.lastname: Narayan
authors.forename: Bamakanta
authors.initials: B
authors.lastname: Garnaik
keywords: Gemifloxacin mesylate; ion-pair; methyl orange; spectrophotometry; validation