Designed peptides as model self-assembling nanosystems: characterization and potential biomedical applications.

Synthesis of nanomaterials via 'molecular self-assembly' allows one to define the properties of the nanomaterial by rational design of the individual constituents. Use of peptides for self-assembly offers the ease of design and synthesis, and provides higher biofunctionality and biocompatibility to nanomaterials. Our work focused on the synthesis, characterization and potential biomedical applications of small self-assembled peptide-based nanosystems. We demonstrated that dipeptides containing the conformational restricting residue alpha,beta-dehydrophenylalanine, self-assembled into nanovesicular and nanotubular structures. The nanosystems could encapsulate and release anticancer drugs, showed enhanced stability to proteinase K degradation, a property crucial for them to have a high in vivo half-life, and exhibited no cytotoxicity towards cultured mammalian cells. The dipeptide nanostructures were easily taken up by cells and could evade uptake by reticuloendothelial systems when injected into healthy laboratory animals. Thus, small self-assembling peptides may offer novel scaffolds for the future design of nanostructures with potential applications in the field of drug delivery.