MICROSPHERES: A PROMISING DRUG CARRIER

Microsphere as a drug carrier is one of the method of delivering therapeutic agent to the target site in a sustained and controlled manner. Microspheres are defined as free flowing powders of spherical shape, consisting of proteins or synthetic polymers, which are either biodegradable or non-biodegradable in nature and ideally having a particle size ranging from 1 – 1000 μm. The main aim of such novel drug delivery system is to overcome the limitations of conventional dosage forms and providing more patient compliance, increase bioavailability and more specifically targeted delivery of drugs or other active agents. This present review articles deals with the ideal characteristics, types, methods of preparation, their characteristics evaluation, in vitro-in vivo correlation and applications of microsphere as drug carrier. There are various methods available today for the preparation of microspheres with the goal of achieving reproducibility and consistency with good entrapment efficiency. The prepared microspheres are then exposed to various evaluation parameters. Therefore microsphere as drug carrier can be used for delivery of various therapeutic agents to the target site and can be surface engineered for further extending their therapeutic applications. Keywords: Microspheres, Drug delivery, biodegradable polymer, bioavailability, Preparation, applications.