Amino acid-nucleotide-lipids: effect of amino acid on the self-assembly properties

Hybrid amphiphiles composed of a lipid covalently linked to biomolecules are attracting considerable attention, owing to their unique physicochemical and biological properties. Herein, we have synthesized novel amino acid-nucleotide-lipids (ANLs), presenting phenylalanine and thymidine residues and saturated or unsaturated diacyl glycerol lipid moieties to investigate the effect of the specific aminoacid moieties on both aggregation properties and interactions of ANLs with single strand polyA RNA. Physicochemical studies (DLS, cryo-TEM, and small angle X-ray scattering) indicate that phenylanaline amino acids inserted at the 5' position of the nucleotide-lipids stabilize multilamellar systems, whereas unilamellar vesicles are formed preferentially in the case of nucleotide-lipids (NLs). Both NLs and ANLs exhibit weak interactions with complementary polyA RNA as revealed by isothermal titration calorimetry investigations. The multilamellar vesicles obtained with ANLs could be used as a versatile carrier, suitable for both hydrophobic and hydrophilic therapeutic molecules.