Isoniazid loaded chitosan microspheres for pulmonary delivery: Preparation and characterization

The objective of the present study was to entrap isoniazid, an Antitubercular drug, in cross linked chitosan matrix and study in vitro lung deposition of powdered chitosan microspheres using Andersen cascade impactor. Ionic cross linker Tripolyphospate was used to make cross linked chitosan microspheres to achieve sustained drug release. Chitosan microspheres were prepared by spray drying method. The spray dried microspheres were characterized for size, shape, drug release and in vitro pulmonary drug deposition. Aerosol properties like fine particle fraction and Mass median aerodynamic diameter were also evaluated. The cross linked microsphere were prepared with entrapment efficiency of 72 to 88 percentages. Spray dried microspheres had mean particle size of 3.6 to 5.2 μm and fine particle fraction of 67 %.