Cell-Laden Supramolecular and Covalent Polymer Hydrogels for High-Shear Delivery: A Design of Experiments Approach

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Effective cell-delivery scaffolds are crucial for regenerative medicine, particularly for complex wound architectures.
• Systematic analysis of cell, polymer scaffold, and biomaterial properties in composite materials is often lacking.

Purpose of the Study:

• To systematically analyze a supramolecular hydrogel of peptide amphiphile (PA) nanofibers for high-shear cell delivery.
• To compare PA hydrogel performance against a covalent alginate hydrogel for cell delivery applications.

Main Methods:

• Utilized a full factorial design of experiments (DoE) to investigate polymer concentration and cell loading effects.
• Assessed mechanical properties, structural integrity, substrate adhesion, and sprayability of both hydrogel types.
• Evaluated cell viability and hydrogel recovery post-high-shear delivery.

Main Results:

• Supramolecular PA hydrogels exhibited shear-thinning and thixotropic properties, enabling effective spray deposition and preserving cell viability.
• PA hydrogels demonstrated remarkable mechanical resilience and recovery post-spray, even at high cell loadings (2 million cells/mL).
• Alginate hydrogels showed significant loss of gel integrity at equivalent cell loadings and were not suitable for spray delivery.

Conclusions:

• Established a robust structure-property relationship for cell-laden supramolecular PA hydrogels for high-shear delivery.
• Highlighted the potential of PA hydrogels as customizable platforms for regenerative medicine, advanced wound care, and 3D printing.
• Demonstrated the superiority of supramolecular PA hydrogels over alginate for demanding cell delivery applications.