Controlled release of oxytetracycline trapped in a matrix of alginate / chitosan coated with Eudragit® fluidized

Abstract

This work is based on a gastroresistant delivery system, in which the drug crosses the gastric medium intact and is controlled released in the enteric medium. The drug selected is Oxytetracycline (OTC), which after be ingested it causes irritation to the gastric mucosa. OTC is an antibiotic of broad-spectrum of the tetracycline family with bacteriostatic action. The method chosen to prepare the microparticles will be the complex coacervation in one step. The natural polymers utilized will be alginate of anionic nature, and chitosan of cationic nature, since they are biocompatibles, non toxic and easy to degradation. Continuing the work of Cruz (2004) financed by FAPESP, it will be carried on the coating of the matrix-drug particles in a Fluidized bed system, using a polymer-based dispersion of Eudragit ®, which is a synthetic polymer gastro anionic nature. In order to avoid the burst effect observed by Cruz (2004), it will be made the optimization of the formulation and polymer coating process. The kinetics of in vitro drug release will be performed by the spectrophotometric method in the acidic and basic dissolution medium, to obtain the dissolution profile in gastric and intestinal fluids. (AU)