Self-assembled peptide-based nanoblocks for drug delivery

Abstract

The exploitation of available self-assembled systems for the effective uptake and release of hydrophobic antitumor or antiviral drugs in cells remains a great challenge. Oligopeptides are highly promising candidates among the multitudinous self-assembled biomaterial systems, owing to their unique properties of sequence adjustability, self-assembly, good biocompatibility, etc. Here, an amphiphilic peptide (Pep1) was designed and synthesized, and can self-assemble into nanoblocks with a size of 100–150 nm and a height of 34 nm upon crosslinking with PO₄³⁻. The assembly mechanism of the nanoblocks was elucidated, and the assembly was found to be driven by synergistic interactions, including the hydrophobic effect, electrostatic interactions, directional H-bonds and polar zippers derived from hydrophilic residues. Moreover, the Pep1/PO₄³⁻ nanoblocks can not only encase drug molecules with a favourable loading rate and rapid release in the presence of trypsin, but also show good biocompatibility. This work may promote the development of self-assembled systems based on peptides for prominent future biomedical applications.