Superb Silk Hydrogels with High Adaptability, Bioactivity, and Versatility Enabled by Photo-Cross-Linking

Area of Science:

• Biomaterials Science
• Biomedical Engineering
• Polymer Chemistry

Background:

• Hydrogels are crucial for biomedical devices due to their biocompatibility.
• Conventional synthetic hydrogels often lack sufficient mechanical strength and durability.
• There is a need for advanced hydrogel fabrication methods that combine mechanical robustness with biological efficacy.

Purpose of the Study:

• To develop a facile and rapid method for creating robust silk fibroin hydrogels.
• To investigate the mechanical properties and cell-supporting capabilities of the novel hydrogels.
• To explore the potential of these hydrogels in various biomedical applications.

Main Methods:

• Utilized photo-cross-linking technology inspired by photosynthesis, employing riboflavin and H2O2.
• Achieved hydrogel formation within 60 seconds through a cyclic cross-linking reaction.
• Incorporated adipose stem cells into the hydrogel matrix for biological assessment.

Main Results:

• Developed highly cross-linked silk fibroin hydrogels with superior elasticity and restorability after 1000 compression cycles.
• Demonstrated that encapsulated adipose stem cells maintained proliferation and stemness (evidenced by sustained OCT4 and SOX2 expression over 21 days).
• Showcased the versatility of the hydrogels for molding into various biomedical structures like microneedles, microcarriers, and bone screws.

Conclusions:

• The photo-cross-linking approach provides a rapid and effective route to synthesize mechanically superior silk fibroin hydrogels.
• These hydrogels effectively support stem cell viability, proliferation, and stemness, making them suitable for cell delivery.
• The developed silk hydrogels offer a promising platform for advanced, adaptable, and machinable biomedical devices.