Abstract
The aim of this study was to formulate nasal amlodipine chitosan microspheres with enhanced bioavailability. The microspheres were prepared by spray-drying method and characterized regarding particle size, morphology, drug entrapment efficiency and in-vitro drug release. Bioavailability of amlodipine was studied in rabbits and compared to intravenous and oral solutions. Results showed that the prepared microspheres characters were dependent on polymer: drug ratio. Microspheres were spherical and had particle size in the range of 2-10 µm. The prepared microspheres were able to sustain amlodipine for 6 h. Nasal chitosan microspheres revealed superior bioavailability over oral solution. Therefore, nasal mucoadhesive chitosan microsphere is promising strategy to improve amlodipine bioavailability via circumventing first-pass metabolism, prolonging nasal residence time and enhancing nasal absorption.
