Biomimetic gels with chemical and physical interpenetrating networks

This study aimed to create and to characterize the functional properties of gels with semi‐interpenetrating network (semi‐IPN) with focus on possible use of these composites in biomedical engineering. Polyacrylamide as a synthetic biocompatible polymer was chosen for the chemical network. The physical network comprised the gel‐forming polysaccharides xanthan gum or gellan gum. Gels were synthesized by radical polymerization of acrylamide in aqueous solutions of polysaccharides. Mechanical and electrical properties of gels with 0.2, 0.4, 0.6, 0.8 and 1.0 wt% content of polysaccharide were investigated. It was found that the inclusion of a small amount of xanthan or gellan into the polymeric network of a polyacrylamide gel significantly shifts the gel electrical potential towards the rest potential of living cells and Young's modulus towards the elasticity limits of biological soft tissues like non‐activated muscles. From the viewpoint of biomedical applications, the main advantage of the proposed composites is that the semi‐IPN structure provides a nonlinear dependence of gel tension on gel deformation, which mimics the elasticity of natural tissues. This feature opens the possibility for the promising use of the proposed gels for musculoskeletal minibioimplants or scaffolds for tissue engineering. © 2018 Society of Chemical Industry