Microparticles based on chitosan and poly(methyl vinyl ether-co-maleic anhydride) for nasal delivery of propranolol hydrochloride

Recently, microsphere technology has been applied in designing formulations for nasal drug delivery. Drugs which are not absorbed from such dosage forms, stand better chance of absorption when formulated in “gelling” microspheres made by using biocompatible materials e.g. starch, gelatin, albumin, chitosan and dextran. In particular, chitosan (CH) is a positively charged linear polysaccharide that is bioadhesive and able to interact strongly with the nasal epithelial cells and the overlaying mucus layer thereby providing a longer contact time for drug. Poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA) is widely used for pharmaceutical purposes. It is a biodegradable polyanhydride and could be an appropiate copolymer for the preparation of particulate dosage forms with bioadhesive or mucoadhesive properties. The aim of this work was firstly to entrap propranolol hydrochloride (PH) within CH-PVM/MA microparticles prepared by spray-drying technique and secondly to characterize the formulation in terms of morphology, size, swelling properties, drug loading and release.