Sequential addition synthesis of guar gum based ternary hydrogels with kinetic asymmetry in drug release.

Currently, biomedical engineering is placing significant emphasis on hydrogels due to their exceptional capabilities in drug delivery, tissue regeneration, tissue adhesion, blood clot prevention, contrast imaging, safeguarding tissues or organs during radiotherapy, and enhancing the biocompatibility of medical implants. This study explores a temperature-controlled sequential addition method to synthesize pH responsive guar gum-sodium alginate hydrogels with PVA as third component. Obtained hydrogels have been observed with kinetic asymmetry in drug release at specific pH. The sequential addition method has augmented thermal stability of products by allowing for distinct crosslinking patterns in the hydrogels produced. Kinetic assymetry of in-vitro drug release has been observed, specifically depending upon drug hydrogel interaction as hydrogen bonding. The blends that were prepared with higher sodium alginate (NaA) contents demonstrated 1st order drug release kinetics due to highest swelling and fast ionic dissociation leads to fast drug release, whereas samples with higher guargum (GG) ratio in compositions presented zero order kinetics due to compact structure and sustained swelling. The maximum drug release achieved within 12 h was 92% in intestine at 7.4 (colon pH), which was subsequently characterized by non-Fickian diffusion due to polymer relaxation.