Self-Assembled Peptide-Carbon Nitride Hydrogel as a Light-Responsive Scaffold Material

Area of Science:

• Bioorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Peptide self-assembly offers a versatile method for creating complex bioorganic hybrid materials.
• Graphitic carbon nitride (g-C3N4) shows promise for photocatalysis but requires structural optimization.

Purpose of the Study:

• To synthesize and characterize Fmoc-diphenylalanine (Fmoc-FF)/g-C3N4 hydrogels for light harvesting and biomimetic photosynthesis.
• To investigate the noncovalent interactions driving the self-assembly and their impact on material properties.

Main Methods:

• Synthesis of Fmoc-FF/g-C3N4 hydrogels via noncovalent interactions.
• Characterization of hydrogel nanostructures and photocurrent density.
• Assessment of NAD+ reduction rates and light-responsive redox biocatalysis.
• Evaluation of the encapsulation and functional retention of photosynthetic components.

Main Results:

• The Fmoc-FF/g-C3N4 hydrogel exhibited a 1.8-fold increase in photocurrent density (0.82 μA cm-1) compared to pristine g-C3N4.
• Effective exfoliation of g-C3N4 nanosheets within the hydrogel network facilitated photoinduced electron transfer.
• The hydrogel achieved a high NAD+ reduction rate of 0.130 mol g-1 h-1 and supported light-responsive redox biocatalysis.
• The scaffold efficiently encapsulated photosynthetic components, maintaining their biological functions.

Conclusions:

• The Fmoc-FF/g-C3N4 hydrogel demonstrates significant potential for advanced biomimetic photosynthesis applications.
• The synergistic integration of peptide nanofibers and g-C3N4 nanosheets enhances light-harvesting and electron-transfer processes.
• The developed hydrogel provides a stable and functional scaffold for integrating biological machinery for artificial photosynthesis.