Interpenetrating polymer networks of poly (2-hydroxyethyl methacrylate co-itaconic acid) and chitosan as a controlled release matrix

Interpenetrating networks of chitosan and poly (2-hydroxyethyl methacrylate co-itaconic acid) p(HEMA-co-IA) were synthesized. FTIR spectra confirmed the crosslinking of chitosan and the polymerization and crosslinking of 2-hydroxyethyl methacrylate (HEMA) with itaconic acid (IA). Swelling properties were studied at different pH levels, and it was shown that such properties depend primarily on chitosan and itaconic acid content and the sensitivity to pH of the network components. The degradation of the materials obtained was performed with lysozyme under simulated physiological conditions. Increased degradation was observed with increasing copolymer content (p(HEMA-co-IA)) in the hydrogel. Creep-recovery analysis studies demonstrated that the materials exhibit viscoelastic behavior, resulting in lower instantaneous deformation of the interpenetrating hydrogels and higher shear modulus. Diclofenac sodium was used as a model drug for controlled release studies. The results indicate that the incorporation of the copolymer increased the concentration of drug released by the hydrogel.