Development and evaluation gastro-retentive floating microspheres of ofloxacin

Abstract

Ofloxacin is a fluoroquinolones antibiotic with a broad spectrum activity against gram positive and negative bacteria. Conventional doses vary from 200-600 mg twice or thrice a day, as per severity of infection and its biological half-life is 5-6 hrs. Ofloxacin is absorbed in GIT and readily soluble in gastric pH of the stomach, so floating microspheres were developed for prolongation of gastric residence time with an aim to improve bioavailability. Eight formulations was prepared by different concentration of ethyl cellulose, HPMC K 4M and HPMC K 15M by non aqueous solvent evaporation technique. Depending upon the drug polymer ratios, the percentage yield is found between 86.75±0.96% to 95.93±0.94% and entrapment efficiency was 70.47± 0.96% to 91.28± 0.82% in all formulations. Microspheres showed a good specificity, spherical and uniform in shape with smooth surface and the mean particle size significantly increase with increasing polymer concentration and it was in the range between 182.41±0.54 to 229.43±0.48 µm. Percentage in-vitro buoyancy of the floating microspheres was in the range of 70.37± 0.68% to 86.07± 0.86%. In-vitro drug release studies was performed in simulated gastric fluid, it is revealed that formulation codes OF-III and OF-VII was found in 97.81±0.94% and 98.80±0.68% drug releases at the end of studies, when compared to all batches due to increases in polymer concentration. Stability studies of selected floating microspheres showed good in results. It could be concluding that the all the formulations were shown satisfactory results and 
suitable for potential therapeutic uses.