Development of Polymer Based Controlled Drug Delivery Systems of Selected Antibacterial Agents

Abstract

This thesis deals with the investigations carried out by the objective of developing controlled release formulations for widely used antibiotics norfloxacin and ofloxacin for the evaluation of their controlled release potential. The first chapter of the thesis deals with a brief introduction to the conventional drug therapy, concept of sustained release drug delivery system, its relevance with respect to oral drug delivery, the anatomy and physiological considerations of the GIT, oral controlled release drug delivery system, significance and reasons for developing oral controlled release drug delivery system (CRDDS), ideal drug candidates for CRDDS, types of sustained/controlled release products, monolithic matrix system as oral CRDDS, mechanism of drug release from natural polymer matrix system and estimation of drugs in biological medium. Literature survey on the investigations that have been carried out so far on the development of controlled release drug delivery systems and current developments for the selected drug candidates is being mentioned. The aim and objectives along with the place of work is presented in the second chapter of the thesis. In particular, it explains the need for designing a suitable drug delivery system for the drug candidates selected in the present investigation. The formulation was optimized using response surface methodology by fitting a second-order model to the response data. The model was found to be satisfactory for describing the relationships between formulation variables and individual response variables, as well as the relationships between formulation variables and the overall desirability. The use of a desirability function appeared to be a useful approach for handling the problem of multiple responses in this case. The optimization method enabled us to predict the values of response variables and overall desirability within the experimental range with good agreement between the predicted and experimental values.