Chitosan hydrogels chemically crosslinked with L-glutamic acid and their potential use in drug delivery

Controlled drug release systems have the characteristics of eliminating or reducing side effects and producing a therapeutic concentration of the drug that is stable in the body. The synthesis of hydrogels from natural polymers allows innovation in new materials that promote more effective, selective and safe therapies, in comparison with hydrogel systems based on synthetic polymers where their main limitation may be their biocompatibility and degradation. For this reason, in this work the synthesis of hydrogels of chitosan crosslinked with glutamic acid is proposed as the basis of new trends in smart materials for their potential use in the controlled release of drugs, the hydrogels were prepared from an amidation reaction between the amino groups of chitosan and the carboxyl groups of L-glutamic acid, using N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC) as activator of the carboxyl groups. The hydrogels obtained were characterized by SEM, FTIR, TGA techniques, swelling kinetics and antimicrobial activity. They exhibited excellent swelling capacity and good performance when exposed to different pH and temperature conditions. The bacterial inhibition percentages demonstrated the antimicrobial activity of chitosan hydrogels and the results obtained potentially favored their use as reservoirs for controlled drug release.