Rheology-directed design of multifunctional human-like skin materials for extrusion-based 3D bioprinting combining...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Severe skin injuries necessitate advanced wound dressings with bioadhesive properties, infection control, and tissue regeneration capabilities.
• Current printable biomaterials often lack the necessary combination of mechanical stability, printability, and biological activity for effective wound management.

Purpose of the Study:

• To develop a printable, bioadhesive hydrogel precursor using a rheology-directed design strategy for extrusion-based 3D printing.
• To evaluate the rheological properties, printability, and preliminary biological functions of the developed hydrogel for potential wound dressing applications.

Main Methods:

• A gelatin/tannic acid/hyaluronic acid/elastin hydrogel precursor was formulated and characterized for rheological properties, including shear-thinning behavior and yield stress.
• The hydrogel precursor was optimized for extrusion-based 3D printing at ambient temperature (25 °C).
• Secondary crosslinking with EDC/NHS was employed to enhance structural stability, and preliminary assessments of tissue adhesion, antimicrobial activity, and wound closure were performed.

Main Results:

• The hydrogel precursor exhibited controllable shear-thinning and thixotropic recovery, suitable for 3D printing.
• The optimized formulation demonstrated good tissue adhesion and in vitro bacteriostatic activity against E. coli and S. aureus.
• Preliminary results in a mouse wound model indicated potential for wound closure, though further evaluation of post-crosslinked stability and cell viability is needed.

Conclusions:

• Rheology-directed formulation is a viable strategy for developing printable bioadhesive hydrogel dressings.
• The developed hydrogel shows promise for treating severe skin injuries, offering adhesion, infection control, and wound repair potential.
• Further research is required to optimize mechanical stability at physiological temperatures and validate efficacy in infected wound models and assess cell viability.