l-Alanine induced thermally stable self-healing guar gum hydrogel as potential drug vehicle for sustained release of hydrophilic drug.

A simple approach for preparing self-healable guar gum-graft-acrylic acid (GG-PAA) hydrogel using l-alanine as a cross-linking agent was introduced for the first time. It drastically modifies the mechanical strength of the hydrogel to G' = 90,570 Pa. Thus, a series of guar gum (GG) based hydrogel was synthesized by varying the concentration of l-alanine from 0.4 to 1% w/v. The hydrogel was characterized by different analytical techniques such as FTIR, HRSEM etc. The mechanical strength of the hydrogel was investigated by rheology analysis and it was observed in terms of storage and loss modulus i.e. G' & G'', respectively. Maximum G' & G'' (90,560 Pa & 60,820 Pa) were observed when 1 wt% of l-alanine was used as a cross-linking agent. This GG based hydrogel have shown excellent swelling i.e. up to 3350%, which indicates its porous network. The synthesized hydrogel has been identified as a controlled drug delivery gel, which releases 98% of the highly water-soluble loaded drug in 140 h.