Novel biodegradable pH-sensitive hydrogels: An efficient controlled release system to manage ulcerative colitis.

Area of Science:

• Polymer Chemistry
• Materials Science
• Pharmacology

Background:

• Ulcerative colitis (UC) requires targeted drug delivery to the colon to enhance efficacy and reduce side effects.
• Conventional drug delivery systems often fail to achieve sufficient drug concentration at the colonic site.
• Developing stimuli-responsive and biodegradable materials is crucial for effective colon-specific drug delivery.

Purpose of the Study:

• To develop and characterize a pH-sensitive, biodegradable interpenetrating polymeric network (IPN) hydrogel.
• To achieve colon-specific delivery of sulfasalazine for ulcerative colitis treatment.
• To optimize colon targeting efficiency and improve drug accumulation while minimizing off-target effects.

Main Methods:

• Pectin was grafted with polyethylene glycol (PEG) and methacrylic acid (MAA) via free radical polymerization to form pectin-g-(PEG-co-MAA) hydrogels.
• Characterization involved FTIR, TGA, DSC, EDX, and XRD to confirm hydrogel stability.
• In vitro swelling, drug release studies at different pH, in vitro degradation using pectinase, toxicological assessment, and in vivo studies using a DSS-induced rat model were performed.

Main Results:

• Characterization confirmed the formation of stable pectin-g-(PEG-co-MAA) hydrogels.
• Hydrogels exhibited pH-sensitive swelling and released sulfasalazine specifically at pH 7.4 (colonic pH).
• Toxicological studies confirmed the safety of the hydrogels, and in vitro degradation showed susceptibility to colonic microflora. In vivo studies demonstrated efficacy in managing UC.

Conclusions:

• The developed pectin-based IPN hydrogels are pH-sensitive, biodegradable, and safe for colon-specific drug delivery.
• These hydrogels show significant potential for targeted delivery of sulfasalazine in ulcerative colitis management.
• The study highlights the successful application of advanced polymer networks for improving therapeutic outcomes in inflammatory bowel disease.