Abstract:

In this paper, cationic amphipathic R peptide (RLARLLRRLARWLR) was chosen to construct peptide-lipid nanoparticle. Recombination and interaction of R peptide with lipid mixture were studied using lipid emulsion clearance assay and blue shift of tryptophan fluorescence assay. The diameter and surface characterization of cationic amphipathic R peptide-lipid nanoparticle (R-LNP) were obtained with transmission electron microscope (TEM), dynamic light scattering (DLS) and zeta potential measurements. MTT assay was used to investigate cytotoxicity of R-LNP. Stability of R-LNP and R peptide against chymotrypsin and trypsin was explored using ultra high performance liquid chromatography (UPLC). The results showed that R peptide caused reconstruction of lipid to form lipid nanoparticle with a diameter of (14.7$\pm $0.1) nm and zeta potential of 17.8 mV. Hydrophobic amino acids of R peptide inserted in the hydrophobic core of lipid nanoparticle. Cytotoxicity of R peptide was retained in R-LNP, of which half-inhibitory concentration for A549 and MCF-7 was (5.93$\pm $0.75) $\mu$mol/L and (4.36$\pm $0.40) $\mu$mol/L respectively. UPLC results showed that R-LNP increased stability of R peptide, facilitating its translational application in vivo.

Key words: cationic amphipathic peptide, lipid nanoparticle, construction, function