Exploring Self-Assembled Cationic Nanostructures of Amphiphilic β-Peptides for Amplifying Drug Delivery Efficiency

Abstract

In this study, a set of short sequences of amphiphilic peptides composed of synthetic amino acids β-alanine and ornithine were designed. The synthesis of these peptides was carried out in a solution phase and then self-assembled into cationic nanostructures. The formation of cationic nanostructures was confirmed using dynamic light scattering (DLS) and the morphology of the nanostructures was studied using transmission electron microscopy (TEM), which revealed that the nanostructure adopted a spherical shape. To gain insight into the conformation of both solid samples and peptide solutions, the Fourier transform infrared (FTIR) and circular dichroism (CD) spectroscopic analysis were performed. Furthermore, the ability of these nanostructures to encapsulate hydrophobic drugs were also investigated. Three different drugs were tested as model drugs: L-dopa, an anti-Parkinson’s drug; curcumin, anti-cancerous drug and tetrabenazine, anti-Huntington’s drug. The nanostructures exhibited the capacity to encapsulate these drugs in varying ratios.