A Reconfigurable Proangiogenic Hydrogel Patch Enabling Minimally Invasive Drug Delivery

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Drug Delivery Systems

Background:

• Hydrogels are crucial for sustained bioactive molecule delivery but require large incisions for implantation, risking complications.
• Current minimally invasive methods for hydrogel delivery, like manual catheter insertion, are skill-dependent and can damage implants.

Purpose of the Study:

• To develop a reconfigurable hydrogel patch capable of self-folding into a tube for catheter delivery and spontaneous unfolding post-implantation.
• To investigate the controlled swelling, degradation, and drug release dynamics of the novel hydrogel system.

Main Methods:

• Assembled a bilayer hydrogel patch using poly(ethylene glycol) diacrylate (PEGDA) and polyethylenimine (PEI) hydrogels.
• Utilized a mathematical model to correlate hydrogel layer properties (expansion ratio, elastic modulus) with self-folding/unfolding dynamics.
• Evaluated sustained protein cargo release and neovascularization enhancement in vivo.

Main Results:

• The hydrogel patch successfully self-folded into a tube and spontaneously unfolded after catheter delivery.
• Mathematical modeling accurately predicted the self-folding and unfolding behavior based on material properties.
• The gel biopatch loaded with angiopoietin 1 significantly promoted neovascularization, nearly doubling vascular density compared to controls.

Conclusions:

• The reconfigurable hydrogel patch offers a viable solution for minimally invasive delivery of therapeutic molecules.
• This technology has broad potential for enhancing therapeutic outcomes in tissue repair and regeneration.
• The controlled self-folding and unfolding mechanism ensures implant integrity and facilitates sustained drug release.