Digambar Yashawant Mali

Micro-particulate systems have already shown their potential as a carrier in delivery of many therapeutic molecules. Due to this potential, such systems are now most preferred over other conventional systems of drug delivery. Micro-carriers (Microspheres) shows features like controlled release, improvement in the residence time and thus enhancing bioavailability of administered drug. Nasal microspheres are now a day’s becoming more popular for delivery of many therapeutic moieties. For building of microparticulate systems polymers from natural and synthetic origins are generally used. Drugs which are not suitable for oral administration due to high first pass effect (i:e presystemic metabolism), instability in gastrointestinal tract can be successfully delivered via nasal route. Systems like mucoadhesive microspheres provide sufficient time for drug to remain in contact with mucosal membrane so as to increase their absorption. This is the basic underlined reason suggests why most of the polar drugs have shown improvement in the bioavaibility when compared with their conventional intranasal formulations. This review mainly focuses on the basic aspects of microspheres as a potential carrier in the drug delivery.

Microsphere is a carrier system for delivery of therapeutic candidate. Nasal microspheres offers significant advantages over other type of drug delivery system. It modulates absorption characteristics of the drug by enhancing drug residence time in the nasal cavity and subsequently may increase bioavailability profile of administered drug. Prior to formulation some physicochemical properties of drug are need to be considered like molecular weight, solubility, pKa and partition coefficient of drug etc. Till date various methods have been adopted for fabrication of nasal microspheres are like spray drying, emulsion crosslinking, Solvent Evaporation etc. Obtained microspheres can characterized for various properties like its morphology, drug content, and zeta potential etc. Present  review mainly focuses on overview of microsphere technology for nasal administration of drug.