Hemlata Kaurav, S. L. HariKumar and Amanpreet Kaur
Microspheres constitute an important part of novel drug delivery system by virtue of their small size and efficient carrier capacity. Due to their short residence time, bioadhesive characteristics can be coupled to microspheres to develop mucoadhesive microspheres. Bioadhesion can be defined as the state in which two materials, at least one of which is biological in nature, are held together for a prolonged time period by means of interfacial forces. Microspheres are the carrier linked drug delivery system in which particle size is ranges from 1-1000 μm range in diameter having a core of drug and entirely outer layers of polymer as coating material. Mucoadhesive microspheres have advantages like efficient absorption and enhanced bioavailability of the drugs due to a high surface to volume ratio, a much more intimate contact with the mucus layer, controlled and sustained release of drug from dosage form and specific targeting of drugs to the absorption site. The present study aims to provide an overview of various aspects of mucoadhesive microsphere based on various polymers, methodology of preparation of mucoadhesive microspheres, method of evaluation and their applications in drug delivery.