Thiol-Functionalized Succinoglycan via Cysteine Grafting: Enhanced Rheological Properties and Antioxidant Activity

Area of Science:

• Biopolymer Chemistry
• Materials Science

Background:

• Succinimide (SG) is a natural polysaccharide with potential applications.
• Modifying SG can improve its functional properties for advanced uses.

Purpose of the Study:

• To synthesize cysteine-modified succinoglycan (SG-Cys).
• To evaluate the impact of cysteine grafting on SG's physicochemical, rheological, and antioxidant properties.
• To assess the cytotoxicity of SG-Cys for potential biomedical applications.

Main Methods:

• Synthesis of SG-Cys via EDC/NHS-mediated amidation.
• Characterization using 1H NMR, FTIR, and Ellman's assay.
• Rheological analysis under varying environmental conditions.
• Antioxidant activity assessed via DPPH and ABTS assays.
• Cytotoxicity testing on HEK-293 cells.

Main Results:

• Successful grafting of cysteine onto succinoglycan confirmed.
• SG-Cys exhibited up to a 1.8-fold increase in viscosity compared to native SG.
• Enhanced viscoelastic properties and responsiveness to environmental stimuli observed.
• Up to a 2.5-fold increase in antioxidant capacity demonstrated.
• SG-Cys showed no significant cytotoxicity.

Conclusions:

• Thiol functionalization of succinoglycan via cysteine grafting significantly enhances its rheological performance and antioxidant activity.
• SG-Cys is a promising multifunctional bioactive polymer.
• Potential applications in biomaterials, drug delivery, and bioengineering systems are suggested.