Porous PVA microspheres for Oxytetracycline delivery

Abstract

Porous PVA microspheres were prepared to investigate their adsorption and release capacity ofoxytetracycline (OTC) in simulated biological fluid (SBF). The highest adsorption capacity of OTC during 2 hours was obtained at pH= 4, being 0.9 mg g-1. The release profile of OTC in SBF from the microspheres showed a burst effect with a cumulative release of 29±4 % within the first thirty minutes due to the immediate release of the OTC adsorbed on the surface of the microspheres, followed by a slower release reaching 41±5% within two hours,which in terms of concentration is equivalent to 4.2 μg/mL, a value close to the minimum inhibitory concentration of pathogens susceptible to OTC in injectable administration methods of therapeutic doses from 10 mg/Kg for farm animals.