Redox-responsive hydrogels of thiolated pectin as vehicles for the smart release of acetaminophen

Redox-responsive hydrogels gained considerable attention as drug delivery systems since they allow releasing of encapsulated drugs under specific conditions. The potentialities of these smart materials can increase considerably with the use of biopolymers; however, this option is barely investigated. In this study, we report an original strategy for the synthesis of a polysaccharide-based hydrogel consisting only of thiolated pectin and exploited it as a potential drug delivery system with redox-responsive properties. Hydrogels of different compositions were synthesized by disulfide crosslinking using a simple one-pot process without additional chemical catalysts. Beyond the complete characterization, we demonstrate that the synthesized hydrogels were quickly degraded in the presence of physiological reducing agents (L-glutathione and L-cysteine), whereas exhibiting high stability in their absence. Acetaminophen (a model drug) was encapsulated into these hydrogels and further released in the absence and presence of reducing agents. These experiments confirmed the redox-responsiveness of the synthesized materials, which can be ranked as an advantage for smart drug release devices. • Pectin-based hydrogel chemically crosslinked through reversible disulfide bonds. • Disulfide bonds formation was induced by potassium persulfate. • The degradation of the formed hydrogel is redox-responsive. • The drug release rate can be tailored according to the hydrogel composition.