Cyclic peptide-inorganic nanoparticles as co-assembled hydrogels for drug delivery

Nanocomposite hydrogels are gaining attention for their versatile applications. These materials can be fabricated from the co-assembly between peptides and inorganic nanoparticles resulting in hydrogels with enhanced mechanical and functional properties. A recent study has shown the co-assembly between laponite and linear peptide amphiphiles, resulting in hydrogels for potential applications in neovascularization and hierarchical mineralization.¹ The latter provides the basis for further exploration of nanosilicate-peptide interactions, paving the way for developing hydrogels tailored for various biomedical applications.

This study introduces a nanocomposite hydrogel formed by co-assembling cyclic octapeptide nanomaterials and nanosilicates (nSi). Cyclic peptide CP1 (cyclo-(D-Leu-Lys-D-Leu-Tyr)₂) self-assembled into elongated nanostructures under a pH-triggered mechanism and high peptide concentrations (1 - 2 %wt). Field emission SEM confirmed the formation of CP1 nanostructures, while FTIR validated the integration of CP1 and nSi within the hydrogel. CD spectroscopy indicated that the ß-sheet structure of CP1 was preserved upon nSi incorporation. Rheological analysis demonstrated enhanced elasticity compared to a nonpeptide control. Drug release studies showed a 40% release of vancomycin over 24 hours, sufficient to eradicate E. coli DH5-α. This novel organic-inorganic nanocomposite hydrogel has the potential to be used for diverse biomedical applications.

References:

1. Okesola et al. ACS Nano (2021). https://doi.org/10.1021/acsnano.0c09814