Highly Reactive Thiol-Norbornene Photo-Click Hydrogels: Toward Improved Processability.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Gelatin is a widely used biomaterial in tissue engineering due to its biocompatibility.
• Existing crosslinking methods for gelatin, such as methacrylamide modification, have limitations in processing and efficiency.
• Developing advanced gelatin-based materials is crucial for improving biofabrication techniques.

Purpose of the Study:

• To synthesize and characterize a novel norbornene-functionalized gelatin (Gel-NB) for enhanced thiol-ene photo-click crosslinking.
• To evaluate the processing capabilities of Gel-NB in two-photon polymerization compared to existing gelatin derivatives.
• To confirm the biocompatibility and cell interactivity of the modified gelatin material.

Main Methods:

• One-pot synthesis of gelatin type B with norbornene functionalities (Gel-NB).
• Characterization of Gel-NB for degree of functionalization.
• Benchmarking Gel-NB processing in two-photon polymerization against gelatin-methacrylamide (Gel-MOD) and gelatin-methacrylamide-aminoethylmethacrylate (Gel-MOD-AEMA).
• Assessment of biocompatibility and cell interactivity.

Main Results:

• Gel-NB was successfully synthesized with controlled norbornene functionalization.
• Gel-NB demonstrated significantly improved processing in two-photon polymerization, requiring lower laser power (20 mW vs. ≥60 mW) and supporting a wider concentration range (≥5 w/v% vs. ≥10 w/v%).
• The functionalization preserved the inherent biocompatibility and cell interactivity of gelatin, with potential for surface grafting.

Conclusions:

• Norbornene-functionalized gelatin (Gel-NB) is a highly promising biomaterial for advanced biofabrication.
• The improved processing characteristics of Gel-NB facilitate more efficient 3D bioprinting and tissue engineering applications.
• Gel-NB offers a versatile platform for incorporating active molecules via thiol-ene click chemistry for tailored biomaterial design.