Liquid Crystalline Period Variations in Self‐Assembled Block Copolypeptides–Surfactant Ionic Complexes

Abstract

We investigate the complexation of ampholytic poly(N‐isopropylacylamide)‐block‐poly‐ (L‐glutamic acid)‐block‐poly(L‐lysine) (PNiPAM‐b‐PLG‐b‐PLLys) triblock copolymers and PNiPAM‐block‐(PLG‐co‐PLLys) diblock copolymers with counter charged anionic and cationic surfactants. Both triblock and diblock copolymers are able to selectively form complexes through either L‐glutamic acid–cationic surfactant or L‐lysine–anionic surfactant ionic pairs, depending on the protonated or deprotonated states of the ampholytic peptide units. The complexes show ordering at multiple length scales: i) the block copolymer length scale (101 nm), ii) the liquid crystalline length scale (100 nm), and, iii) the peptidic secondary structures length scale (100 nm). We show that the liquid crystalline period can be tuned by varying the random/block copolypeptide architectures and the composition of the ampholytic amino acid species.magnified image

Self-assembly of polypeptide-based copolymers into diverse aggregates

“…In practice, self-assembled hierarchical structures can be prepared from both pure multiblock copolymers 19,[121][122][123][124][125][126] and block copolymer-based mixture systems. [127][128][129][130][131][132][133][134][135] For the latter case, small molecules, metaligand, block copolymers and homopolymers are usually used as a second component.…”

Synthesis and Characterization of pH‐Responsive Copolypeptides Vesicles for siRNA and Chemotherapeutic Drug Co‐Delivery

“…[16][17][18][19][20][21] Double-hydrophilic block copolypeptides used in the formation of polymersomes have become an interesting class of block copolymers because of their full water solubility, ''smart'' self-assembly behaviors, ability to interact with substrates, and potential as environment friendly and biocompatible substitutes for aggregates formed from organic solvents. [22] RodriguezHernandez and Lecommandoux have used a zwitterionic block copolypeptide (poly(L-glutamic acid)-b-poly(L-lysine)) to form a pH-sensitive schizophrenic polymersome that can be reversibly produced as a function of pH. [17] Over the past few decades, researchers have shed greater light on multifunctional carriers that jointly deliver a chemotherapeutic drug and genetic material, such as pDNA or siRNA.…”

“…Recently, copolypeptides have received much attention due to their tunable chemical structures and suprastructure formation as well as attractive applications in various areas . Double‐hydrophilic block copolypeptides used in the formation of polymersomes have become an interesting class of block copolymers because of their full water solubility, “smart” self‐assembly behaviors, ability to interact with substrates, and potential as environment friendly and biocompatible substitutes for aggregates formed from organic solvents . Rodriguez‐Hernandez and Lecommandoux have used a zwitterionic block copolypeptide (poly( l ‐glutamic acid) ‐b‐ poly( l ‐lysine)) to form a pH‐sensitive schizophrenic polymersome that can be reversibly produced as a function of pH …”

Three‐dimensional crystalline supramolecular nanostructures from self‐assembly of rod–coil molecules incorporating lateral carboxyl group in the middle of the rod segment

“…A considerable amount of research has been undertaken to control the shapes and sizes of supramolecular nanostructures with potential applications in fields such as materials science, molecular electronics and biomimetic chemistry . Rod–coil molecules have a strong tendency to self‐assemble into diverse supramolecular nanoscale structures . Self‐assembly of rod–coil block molecules provides various supramolecular nanostructures in the bulk, e.g.…”