Author(s): NN.Hire*and DV. Derle
Tetracycline an antibiotic was selected as drug for the experiment. Chitosan microspheres of Tetracycline were prepared by spray drying technique using chitosan as a rate controlling polymer and the microspheres were evaluated. Chitosan microspheres were spherical, discrete, free flowing and multinucleate monolithic type. The mean size range was found for formulation in the range of 17.24 to 19.02 μ. Entrapment efficiency was in the range of 82.862 to 89.758 %. The FTIR and DSC study confirmed that no chemical interaction took place during entrapment process. The X-ray diffraction study indicates the amorphous dispersion of the drug after entrapment in to microspheres. Zeta potential study shows positive result. SEM study has revealed that the spheres were almost spherical in shape with rough outer surface. The effect of polymer on release profile of drug was calculated. Tetracycline release from the chitosan microspheres was slow over 10 hr. and dependant on core: coat ratio and size of microspheres. Drug release was by higuchi release kinetic mechanism. Good linear relationship was observed between core: coat ratio of the microspheres and release rate. Chitosan microspheres of Tetracycline exhibited good controlled release characteristics and were found suitable for once a day oral controlled release products.