Physical Characteristics Of Ofloxacin Tablets sold in Uyo and Quantitative Assay by Novel Ion-Pair Complexation Technique

Résumé

Ofloxacin is a flouroquinoline antibiotic frequently prescribed for the treatment of various bacterial infections. Quality assessments were carried out on ten brands of ofloxacin tablets, purchased randomly from various pharmacies in Uyo, Akwa Ibom State, Nigeria and coded A-J. These were subjected to standard physical tests to determine their respective disintegration times, weight uniformity, hardness, friability characteristics and dissolution profiles using standard methods. Quantitative assay was by a spectrophotometric measurement of the ion-pair complex of the drug with bromothymol blue (BTB). All the brands met requirements for weight uniformity and disintegration characteristics. All the brands except brands B, E and F passed the USP specification of 80% dissolution in 30 minutes for uncoated ofloxacin tablets. The f1 and f2 values of the various brands, in comparison with the innovator product (brand I) showed that brands A,B,D,E,H and J could be used interchangeably with brand I. Brands F and J showed suboptimal friability values. Brand B showed suboptimal hardness value. The calibration curve for reference ofloxacin with BTB at 410 nm was linear over a concentration range of 0.00-20.00 ?g/ml. The variation of absorbance with concentration showed excellent correlation with coefficient of correlation (r) of 0.9999 and coefficient of determination (r2) of value 0.9998. All the brands met the USP requirement for content of active ingredient (100.0-110.0%). The recovery of the drug from tablets ranged between 97.54-100.3%. The spectrophotometric assay method used is a simple, sensitive, economical and extraction-free method. It is recommended for routine quantitative analysis of ofloxacin tablets.