Chitosan microspheres prepared by spray drying.

P He; S S Davis; L Illum

doi:10.1016/s0378-5173(99)00125-8

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Chitosan microspheres prepared by spray drying.

P He·S S Davis·L Illum

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Abstract

Non-crosslinked and crosslinked chitosan microspheres were prepared by a spray drying method. The microspheres so prepared had a good sphericity and a smooth but distorted surface morphology. They were positively charged. The particle size ranged from 2 to 10 micron. The size and seta potential of the particles were influenced by the crosslinking level. With decreasing amount of crosslinking agent (either glutaraldehyde or formaldehyde), both particle size and zeta potential were increased. Preparation conditions also had some influence on the particle size. DSC studies revealed that the H2 antagonist drug cimetidine, as well as famotidine was molecularly dispersed inside the microspheres, in the form of a solid solution. The release of model drugs (cimetidine, famotidine and nizatidine) from these microspheres was fast, and accompanied by a burst effect.

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Biocompatible Materials Biopolymers Calorimetry, Differential Scanning Chitin Chitosan Cimetidine Cross-Linking Reagents Delayed-Action Preparations Famotidine Histamine H2 Antagonists Microscopy, Electron, Scanning Microspheres Molecular Weight Nizatidine Particle Size Viscosity Journal Article

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P He, S S Davis, L Illum. 1999-09-30. Chitosan microspheres prepared by spray drying.. https://doi.org/10.1016/s0378-5173(99)00125-8

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