Fabrication and evaluation of levofloxacin hemihydrate floating tablet

The objective of this work was to develop and evaluate the levofloxacin hemihydrate floating formulations (F1-F9). Selection of optimized batch was done by model dependent approach and novel mathematical approach. F1-F9 batches were prepared by direct compression method using Gelucire 43/01 (hydrophobic) and hydroxypropylmethylcellulose (hydrophilic) polymer in different ratios. The floating tablets were evaluated for uniformity of weight, hardness, friability, drug content, in vitro buoyancy and in vitro release studies. Various models were used to estimate kinetics of drug release. The criteria for selecting the most appropriate model were based on the goodness-of-fit test and lowest sum of square residual and Fischer’s ratio. In vitro release study reveals that the release rate of drug was decreased by increasing the proportion of Gelucire 43/01, 5 to 40%. The release rate of levofloxacin hemihydrates from matrices was mainly controlled by the hydrophilic and hydrophobic polymer ratio. Matrix tablet containing 25% HPMC K4M and 15% Gelucire 43/01 (F4 batch) showed a release as target profile. Optimal batch (F4) was selected by regression analysis which followed Higuchi kinetic. Novel mathematical approach was applied to determine the deviation in area under the curve between predicated and observed dissolution data which found to be lowest in optimal batch. The drug release was found to be function of ratio of hydrophobic to hydrophilic matrixing agents.