Biodegradable High-Strength Hydrogels with Injectable Performance Based on Poly(l-Glutamic Acid) and Gellan Gum

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Biodegradable hydrogels are crucial for tissue engineering, particularly for load-bearing tissue reconstruction.
• Clinical applications require hydrogels with high mechanical strength and minimally invasive delivery methods.

Purpose of the Study:

• To develop a biodegradable, high-strength, and injectable hydrogel for tissue engineering applications.
• To evaluate the mechanical properties, injectability, cytocompatibility, and degradation behavior of the novel hydrogel.

Main Methods:

• Synthesized PLGA-APEG and GG-MA biomacromolecules.
• Developed PLGA/GG hydrogels via one-step photo-cross-linking.
• Assessed mechanical properties (compression stress, fracture energy, storage modulus).
• Evaluated injectability and in situ cross-linking in mice with adipose-derived stem cells (ASCs).
• Determined ASC viability and hydrogel degradation over time.

Main Results:

• PLGA/GG hydrogels demonstrated high mechanical strength (0.53 MPa compression stress, 7.7 ± 0.2 kJ m^-2 fracture energy).
• The hydrogel precursor exhibited excellent injectability and in situ gelation for subcutaneous cell delivery.
• High ASC viability (84.0 ± 1.7%) and cytocompatibility were observed over 21 days.
• The hydrogels showed ideal degradation profiles (60 ± 5% degradation in PBS after 11 weeks) and supported tissue infiltration without inflammation.

Conclusions:

• The developed PLGA/GG hydrogels possess high strength, injectability, biocompatibility, and biodegradability.
• These hydrogels show significant potential for load-bearing tissue regeneration and other tissue engineering applications.