A REVIEW ON MICROSPHERES A NOVEL DRUG DELIVERY SYSTEM FOR MULTI-PARTICULATE DRUG RELEASE

A new era of science and technology has evolved in pharmaceutical research focused on the development of different novel drug delivery systems. The evolution of an existing drug from its traditional form to a novel delivery system may considerably improve its performance in aspects of efficacy, safety, and patient compliance. The goal of any drug delivery system is to provide a therapeutic amount of drug to the proper site in the body and then maintain the desired drug concentration. The microsphere is typically injected, but oral dosage forms are being developed to improve the treatment of gastrointestinal conditions. In future microspheres will find the central place in novel drug delivery, particularly in diseased cell sorting, diagnostics, genetic materials, targeted and effective drug delivery. Microspheres are multiparticulate drug delivery systems which are prepared to obtain prolonged or controlled drug delivery to improve bioavailability, stability and to target the drug to a specific site at a predetermined rate. These delivery systems offer numerous advantages compared to conventional dosage forms, which include improved efficacy, reduced toxicity, improved patient compliance, and convenience. Such systems often use macromolecules as carriers for the drugs. The current aim of this review is to study various aspects of the microparticulate drug delivery system including a method of formulation, evaluation & characterization. The present review highlights various types of microspheres, different methods of preparation, its applications and also various parameters to evaluate their efficiency. Microspheres are various types like bioadhesive microspheres, magnetic microspheres, floating microspheres, radioactive microspheres, polymeric microspheres, biodegradable polymeric microspheres, synthetic polymeric microspheres and are prepared by methods like spray drying, solvent evaporation, single emulsion technique, double emulsion technique, emulsion cross-linking method, multiple emulsion method, phase separation coacervation technique, spray drying and solvent extraction. A most important application is that it is used for targeting tumors using anticancer drugs. Being more stable, it has an advantage over other delivery systems like liposomes. It is an important carrier for safe and effective in-vivo drug delivery.