pH‐Sensitive Vesicles Containing a Lipidic β‐Amino Acid with Two Hydrophobic Chains

Abstract

The lipidic beta-amino acid 2-(aminomethyl)-2-pentadecylheptadecanoic acid (1) was synthesized via the alkylation of the C(alpha)-atom of fully protected beta-alanine. Mixed large unilamellar vesicles with a diameter between 100 and 200 nm containing POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) and 1 at a molar ratio of 9 : 1 were prepared and found to have a surface charge which is dependent on pH. At slightly acidic pH, the vesicles were positively charged, and at alkaline pH negatively charged. Dynamic light scattering, zeta potential, and cryo-transmission electron-microscopy measurements indicated that the mixed vesicles fused at pH 4-5 with negatively charged mixed vesicles composed of POPC and POPG (9.8 : 1, molar ratio), POPG being 1-palmitoyl-2-oleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)].

Versatile Phospholipid Assemblies for Functional Synthetic Cells and Artificial Tissues

“…The abovementioned methods are the main ways to produce GUVs. Beside these, many other methods have been developed, including microfluidic jetting method, [ 96–99 ] modified emulsion transfer method, [ 100,101 ] hydrogel‐assisted hydration method, [ 102 ] and the fusion of small vesicles [ 103–109 ] in the presence of divalent cations, fusogenic peptides, or PEG.…”

Novel Materials From the Supramolecular Self-Assembly of Short Helical β3-Peptide Foldamers

“…Given that self-assembly of β 3 -peptides is unperturbed by the steric bulk of the side chain while the presence of a hydrophobic sequence further inhibits the lateral assembly resulting in uniform fiber morphology, β 3 -peptide amphiphiles in which a lipid chain moiety is incorporated into a β 3 -peptide template have been synthesized and shown to undergo self-assembly. The first study reporting a β 3 -peptide-based amphiphile described the synthesis of a β 3 -amino acid containing two acyl chains which, when mixed with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, self-assembled to give lipid-like vesicles (Capone et al, 2008). More recently, an N-acetylated β 3 -peptide containing a lipid chain was synthesized, which self-assembled to form a hydrogel which was both a mechanically stable and biocompatible hydrogel (Motamed et al, 2016), illustrated in Figure 8B–d1.…”

Application of Nickel(II) Complexes to the Efficient Synthesis of ?- or ?-Amino Acids

“…[19][20][21][22][23] However, despite the substantial interest in these amino acids and their applications in drug design, there are few synthetic approaches for preparing these compounds, with most of them being rather impractical. [24][25][26][27][28] We have successfully synthesized dialkylated products of nickel(ii) complexes of β-alanine Schiff base and developed a practical and highly efficient route to synthesize sterically constrained symmetrically α,αdisubstituted β-amino acids (Scheme 4). [29] In the course of our studies to prepare α,αdisubstituted β-alanines in this study, we unexpectedly obtained α,α-disubstituted aldehydes.…”