Mechanochemical functionalization of disulfide linked hydrogels

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Cell Biology

Background:

• Poly(ethylene glycol) hydrogels are widely used in biomedical applications.
• Functionalizing hydrogels often requires complex chemical modifications.
• Disulfide bonds offer a potential mechanism for dynamic material response.

Purpose of the Study:

• To develop a force-induced functionalization method for poly(ethylene glycol) hydrogels.
• To investigate the use of mechanical stress to trigger chemical reactions within hydrogels.
• To demonstrate the application of this technique for patterning cell adhesion.

Main Methods:

• Utilizing poly(ethylene glycol) hydrogels crosslinked with disulfide linkages.
• Applying mechanical force (compression or tension) to induce disulfide bond rupture.
• Facilitating Michael-type addition reactions between ruptured disulfide bonds and acceptor molecules.
• Employing lithographically structured stamps for controlled compression and patterning.
• Assessing cell adhesion to patterned hydrogel surfaces.

Main Results:

• Applied force successfully induced rupture of disulfide linkages in the hydrogel.
• Ruptured disulfide linkages reacted with acceptor molecules, leading to hydrogel functionalization.
• Compression of the hydrogel using a patterned stamp resulted in localized functionalization.
• Cells predominantly adhered to the regions of the hydrogel that experienced compression and subsequent functionalization.

Conclusions:

• Force-induced functionalization of disulfide-linked poly(ethylene glycol) hydrogels is feasible.
• This method provides a novel way to pattern biomolecules and control cell adhesion.
• The technique offers a versatile platform for creating cell-interactive materials with spatial control.