Design of novel multifunctional Oxaprozin delivery system based on dual-sensitive poly(2-hydroxypropyl acrylate/itaconic acid) hydrogels

Series of novel dual-sensitive poly(2-hydroxypropyl acrylate/itaconic acid) hydrogels were designed as multifunctional drug delivery system which can provide several advantages including drug protection, self-regulated oscillatory release and targeted delivery to a single entity. The hydrogels were synthesized by the free-radical crosslinking copolymerization and evaluated as carriers for hydrophobic drug, Oxaprozin, with specific controlled release properties. Structural, morphological, thermal, surface charge, swelling and antimicrobial properties of the hydrogels were investigated for unloaded and Oxaprozin-loaded samples. Swelling studies demonstrated pH- and temperature-sensitivity of drug-free and drug-loaded P(HPA/IA) hydrogels. The results of swelling and oscillatory swelling, and swelling behavior of drug-free, and drug-loaded hydrogels in simulated gastrointestinal conditions, and in vitro Oxaprozin release studies confirmed these hydrogels as a highly effective colon-specific drug delivery system with excellent performance of long-term controlled release. These unique properties make the P(HPA/IA) hydrogels highly attractive materials for developing multifunctional drug delivery systems. (C) 2015 Elsevier B.V. All rights reserved.