Self-aggregates of oligoarginine-conjugated poly(amino acid) derivatives as a carrier for intracellular drug delivery

Abstract

Nx-2,2,4,6,7-Pentamethyldihydrobenzofuran-5-sulfonyl (Nx-Pbf)-protected oligoarginine was directly conjugated to poly(amino acid) derivatives modified with a long alkyl chain. The final concentration of conjugated peptides was easily controlled by the feed ratio of oligoarginine to polymer backbone and a final soluble polymeric system was obtained by the deprotection of Nx-Pbf groups. The polymeric conjugates formed stable self-aggregates of size range of 8–40 nm in aqueous solution and effectively internalized into HeLa cells by adsorptive endocytosis.