PH- and temperature-sensitive semi-interpenetrating network hydrogels composed of poly(acrylamide) and poly(c-glutamic acid) as amoxicillin controlled-release system

Abstract

Hydrogels of semi-interpenetrating networks composed of poly(acrylamide) (PAAm) and poly(γ-glutamic acid) (γ-PGA)with different proportionswere studied as potential amoxicillin controlled-release devices. The effects of the hydrogels composition, pH, and temperature on the kinetics and final release of amoxicillin were determined in batch experiments.The release kinetic testswere conducted using a buffer solution as the release medium under pHconditions of 3 and 7.2, and temperature of 25, 37, and 45 °C. The final percentage of amoxicillin released from the hydrogels was found to increase with temperature, pH, and the amount of γ-PGA in the hydrogels formulation. Overall, equilibrium conditions in the kinetics experiments were achieved within 240 min of hydrogel-solution contact.The overall rate of amoxicillin releasewas represented with a two-parameter empirical model as a function of time. © 2011 Springer-Verlag.