Embedding Well-Defined Responsive Hydrogels with Nanocontainers: Tunable Materials from Telechelic Polymers and...

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Drug Delivery Systems

Background:

• Thermoresponsive hydrogels offer tunable properties for controlled release applications.
• Cyclodextrins (CDs) can be incorporated into hydrogel networks to enhance drug loading and release modulation.
• Thiol-ene click chemistry provides an efficient method for hydrogel network formation.

Purpose of the Study:

• To design and synthesize novel thermoresponsive hydrogels incorporating cyclodextrin (CD) crosslinkers.
• To investigate the fabrication of these hydrogels using thiol-reactive telechelic polymers and thiol-ene conjugation.
• To evaluate the physicochemical properties, cytocompatibility, and drug release behavior of the synthesized CD-containing hydrogels.

Main Methods:

• Synthesis of hydrophilic telechelic polymers with thiol-reactive end groups.
• Fabrication of hydrogels via thiol-ene click reaction with multivalent thiol-containing CDs.
• Characterization of hydrogel properties: morphology, water uptake, rheology, and residual thiol content.
• Assessment of cytocompatibility using fibroblast cell viability assays.
• Evaluation of puerarin loading and controlled release kinetics at different temperatures.

Main Results:

• Clear, transparent hydrogels were formed with good conversion rates (79-89%) using thiol-ene click reactions.
• Hydrogels exhibited moderately well-defined network structures and tunable physical properties.
• The hydrogels demonstrated excellent cytocompatibility with low toxicity to fibroblast cells.
• Drug release studies showed a slower, sustained release of puerarin at physiological temperatures compared to ambient conditions.
• Rheological analysis confirmed network structure collapse near physiological temperatures, influencing drug release.

Conclusions:

• A versatile strategy for fabricating thermoresponsive, CD-containing hydrogels with controlled network structures was developed.
• The hydrogels exhibit promising potential for controlled drug delivery, particularly for antiglaucoma medications like puerarin.
• Temperature serves as an effective stimulus to modulate drug release kinetics by altering hydrogel network compactness.