Single-Walled Carbon Nanotubes As Fluorescent Probes for Supramolecular Self-Assembly Complexes

Semiconducting single-walled carbon nanotubes (SWCNTs) are distinguished by their fluorescence in the near-infrared range, which overlaps with the transparency window of biological samples, and they do not photobleach or blink. Utilizing their unique optical properties, SWCNTs can be rendered optical probes for the characterization and analysis of bio-inspired peptide-based hydrogels. Peptide hydrogels, formed through the supramolecular self-assembly of conjugated amino acids, provide versatile three-dimensional scaffolds for applications in cell culture, tissue engineering, and regenerative medicine. The inherent properties of these amino acids or peptides, notably their limited solubility in water, drive them to self-assemble into elongated fibrillary nanostructures, ultimately creating self-supporting hydrogel matrices. We integrate near-infrared fluorescent SWCNTs into these peptide hydrogels as dynamic fluorescent probes, offering real-time insights into the morphological and structural evolution of the hydrogels. This approach not only enhances our understanding of the self-assembly mechanisms at play but also opens new avenues in supramolecular science. The integration of SWCNTs into the supramolecular structures showcases their potential as a powerful tool for long-term, non-invasive monitoring, with immense promise for numerous biomedical applications.