Polysaccharide and poly(methacrylic acid) based biodegradable elastomeric biocompatible semi-IPN hydrogel for controlled drug delivery.

Nanoparticles embedded semi-interpenetrating (semi-IPNs) polymeric hydrogels with enhanced mechanical toughness and biocompatibility could have splendid biomedical acceptance. Here we propose poly(methacrylic acid) grafted polysaccharide based semi-IPNs filled with nanoclay via in situ Michael type reaction associated with covalent crosslinking with N,N-methylenebisacrylamide (MBA). The effect of nanoclay in the semi-IPN hydrogel has been investigated which showed significant improvement of mechanical robustness. Meanwhile, the hydrogels showed reversible ductility up to 70% in response to cyclic loading-unloading cycle which is an obvious phenomenon of rubber-like elasticity. The synthesized semi-IPN hydrogel show biodegradability and non-cytotoxic nature against human cells. The live-dead assay showed that the prepared hydrogel is a viable platform for cell growth without causing severe cell death. The in vitro drug release study in psychological pH (pH = 7.4) reveals that the controlled drug release phenomena can be tuned by simulating the environment pH. Such features in a single hydrogel assembly can propose this as high performance; biodegradable and non-cytotoxic 3D scaffold based promising biomaterial for tissue engineering.

Design of psyllium-g-poly(acrylic acid-co-sodium acrylate)/cloisite 10A semi-IPN nanocomposite hydrogel and its mechanical, rheological and controlled drug release behaviour.

Soft biomaterials derived from polysaccharides are generally suffers from lack of mechanical robustness and instability. The naturally occurring highly abundance low cost polysaccharide has immense aspect as biomaterial after functionalization which can be designed as stretchable and rubber-like elastic with reversible ductility. A highly swellable, stretchable, low creep, non-cytotoxic nanocomposite hydrogel has been fabricated by simple one-pot Michael type covalent grafting of acrylic acid based copolymer onto psyllium biomacromolecular chian by free radical gelation technique. The fabricated hydrogel was rheologically tested which implies its viscoelastic and thixotropic like features. The porous morphology of the hydrogel was confirmed by scanning electron micrograph. The cryo-transmission electron micrograph shows the random dispersion of the nanoclay (cloisite 10A) tactoids in exfoliated as well intercalated forms. These random distributions of clay nanosheets also enhance the mechanical toughness and reversible ductility of the hydrogels which was also supported by the mechanical and loading-unloading cycle measurement. Nonetheless, the nanocomposite hydrogel was non-cytotoxic against human cell-line (human osteosarcoma) and shows good cell attachment of live cells in a 5-day 'live-dead' assay with almost negligible quantity of cell death. These attributes can promote this material as a soft biomaterial for controlled release device with mechanical robustness and rubber-like elasticity.