Stretchable, anti-bacterial hydrogel activated by large mechanical deformation

Area of Science:

• Materials Science
• Biomedical Engineering
• Polymer Chemistry

Background:

• Hydrogels are widely used for delivering molecular cargos triggered by mechanical force.
• The brittleness of traditional hydrogels limits strain application and controllable molecular release rates.
• Uncontrolled diffusion, especially for small molecules, diminishes the impact of mechanical stimuli on release kinetics.

Purpose of the Study:

• To address limitations of conventional hydrogels by developing a stretchable system combined with cyclodextrin for enhanced molecular delivery.
• To investigate the effect of incorporating cyclodextrin acrylate into polyacrylamide gels on molecular release rates under mechanical stretching.
• To evaluate the potential of these novel hydrogels for controlled drug delivery applications.

Main Methods:

• Synthesis of cyclodextrin acrylate and its incorporation into a polyacrylamide hydrogel matrix.
• Fabrication of stretchable hydrogels capable of up to 100% strain.
• Characterization of molecular release rates from hydrogels with varying cyclodextrin acrylate content and degrees of stretching.
• Inhibition of E. coli growth using quinine-loaded hydrogels under mechanical stimulation.

Main Results:

• Hydrogels with cyclodextrin acrylate (DS_A = 2.3) exhibited lower release rates without stretching compared to controls.
• A significant increase in molecular release rate was observed with increasing mechanical stretching, particularly for gels with DS_A = 2.3.
• Stretched hydrogels loaded with quinine effectively inhibited E. coli growth, demonstrating controlled molecular delivery.

Conclusions:

• Combining stretchable hydrogels with cyclodextrin effectively overcomes limitations of brittleness and uncontrolled diffusion.
• The developed polyacrylamide-cyclodextrin hydrogel system offers tunable molecular release rates controlled by mechanical strain.
• This technology holds promise for improving controlled molecular delivery systems and enhancing the efficacy of therapeutic cargos.