Sustained Delivery of Molecules Using Peptide Surfactants and Uses Thereof

A drug delivery composition comprising a self-assembled nanostructure and a biologically active molecule, wherein the nanostructure comprises a plurality of surfactant peptides and wherein the surfactant peptides have a formula selected from the group consisting of:

• a. (Φ)m(+)n (Formula (1)),
• b. (+)n(Φ)m (Formula (2)),
• c. (Φ)m(−)n (Formula (3)),
• d. (−)n(Φ)m (Formula (4)),
• e. (−)n(Φ)m(−)n (Formula (5)),
• f. (+)n(Φ)m(+)n (Formula (6)),
• g. (Φ)m(−)n(Φ)m (Formula (7)),
• h. (Φ)m(+)n(Φ)m (Formula (8)),
• i. (+)n(Φ)m(−)n (Formula (9)), and
• j. (−)n(Φ)m(+) (Formula (10)),
• wherein:
• (Φ) represents independently for each occurrence, a natural or non-natural amino acid comprising a hydrophobic side-chain;
• (+) represents independently for each occurrence a natural or non-natural amino acid comprising a side-chain that is cationic at physiological pH;
• (−) represents independently for each occurrence a natural or non-natural amino acid comprising a side-chain that is anionic at physiological pH;
• wherein the terminal amino acids are optionally substituted;
• m for each occurrence represents an integer greater than or equal to 5;
• and
• n for each occurrence represents an integer greater than or equal to 1;
• and further wherein the biologically active agent is encapsulated within the nanostructure.