Kinetically Controlled Sequential Growth of Surface‐Grafted Chiral Supramolecular Copolymers

Abstract

We report a facile strategy to grow supramolecular copolymers on Au surfaces by successively exposing a surface-anchored monomer to solutions of oppositely charged peptide comonomers. Charge regulation on the active chain end of the polymer sufficiently slows down the kinetics of the self-assembly process to produce kinetically trapped copolymers at near-neutral pH. We thereby achieve architectural control at three levels: The β-sheet sequences direct the polymerization away from the surface, the height of the supramolecular copolymer brushes is well-controlled by the stepwise nature of the alternating copolymer growth, and 2D spatial resolution is realized by using micropatterned initiating monomers. The programmable nature of the resulting architectures renders this concept attractive for the development of customized biomaterials or chiral interfaces for optoelectronics and sensor applications.

Tuning the pH‐Switch of Supramolecular Polymer Carriers for siRNA to Physiologically Relevant pH

“…The C 3 ‐symmetrical dendritic peptide comonomers 1 and 2 were synthesized using a previously reported convergent synthetic approach ( Figure 1 A) . We first employed standard Fmoc solid‐phase peptide synthesis to prepare a Fmoc‐NH‐Phe‐His‐Phe‐His‐Phe‐OH peptide 3 .…”

“…The C 3 symmetrical dendritic peptide comonomers 1 and 2 were synthesized using a previously reported convergent syn thetic approach (Figure 1A). [12,13,22] We first employed standard Fmoc solidphase peptide synthesis to prepare a FmocNHPhe HisPheHisPheOH peptide 3. Amidation of the Cterminus with a tetraethylene glycol or a primary amine functionalized Newkometype dendron [23] extended with a hexyl spacer, fol lowed by deprotection of the Nterminus led to the structures 6 and 8.…”

Controlling supramolecular polymerization through multicomponent self‐assembly

“…25). 339 Reminiscent to solid-phase synthesis approaches, the sequential addition of anionic and cationic monomers allowed for the step-wise growth of supramolecular strictly alternating copolymers, which were characterized using surface plasmon resonance (SPR), sum frequency generation (SFG) vibrational spectroscopy, and AFM in water. Charge regulation was suggested to passivate the growing chain end of the polymer and therefore to slow down the kinetics of the self-assembly process.…”

“…The combination of both allowed the formation of surface confined and kinetically trapped chiral supramolecular polymers, with a tuneable height in the range of 5-19 nm, a high degree of secondary order and precise lateral positioning in spatially resolved micropatterns. 339 George and coworkers reported the co-assembly of pconjugated amphiphilic building blocks. [340][341][342][343][344][345][346] Using the electron-rich coronene/electron-deficient methyl viologen pair, 340 or oligo(phenylenevinylene) (OPV1)/perylene diimide (PDI1) pair, 341 the formation of supramolecular alternating electron-donor/acceptor arrays were obtained.…”

Supramolecular Copolymerization as a Strategy to Control the Stability of Self‐Assembled Nanofibers

“…[1][2][3][4][5][6] Introducing such ac oncept in the area of supramolecular polymers will expand their potential in applications and demonstrate the advantage of am odular, non-covalent synthetic approach. [7][8][9][10] In the last two decades, these supramolecular polymers have been extensively studied to understand the mechanisms behind their polymerization process, [11] with the aim to develop new motifs that could result in polymers with superior properties.A lso,s ignificant progress has been made in the area of supramolecular copolymerizations to control the microstructure of the copolymers formed. [12][13][14][15] Am ajor challenge to be addressed in these supramolecular copolymers is the ability to control their stability and/or dynamic behavior in the equilibrium exchange dynamics between monomers and polymers.…”