POSS as a versatile platform for developing multifunctional water-soluble photoinitiators

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Conventional photoinitiators lack control over hydrogel network topology post-initiation.
• Developing photoinitiators that actively influence network structure is crucial for advanced material design.

Purpose of the Study:

• To design and synthesize novel multifunctional photoinitiators for active modulation of hydrogel crosslinking.
• To investigate the impact of these nanophotoinitiators on hydrogel properties and 3D printing performance.

Main Methods:

• Synthesis of polyhedral oligomeric silsesquioxane-based nanophotoinitiators (POSS-PIs) by functionalizing POSS with polyethylene glycol (PEG) chains and coupling with I2959.
• Incorporation of POSS-PIs into hydrogel formulations (GelMA/HEMA).
• Characterization of photopolymerization efficiency, crosslinking density, mechanical properties, swelling behavior, and biocompatibility of the resulting hydrogels and 3D printed scaffolds.

Main Results:

• POSS-PIs act as multifunctional junctions, enhancing photopolymerization efficiency and crosslinking density.
• Hydrogels with POSS-PIs showed an 8.30-fold increase in toughness, maintained high stretchability, and exhibited controlled swelling.
• 3D printed GelMA/HEMA-POSS scaffolds demonstrated excellent biocompatibility, supporting cell adhesion, proliferation, and network formation over 10 days.

Conclusions:

• POSS-PIs serve as multifunctional photoinitiators that precisely tailor hydrogel properties.
• This dual functionality offers significant advantages over conventional photoinitiators for hydrogel network formation.
• POSS-PIs show great potential for applications in 3D bioprinting and advanced biomedical engineering.