pH‐Controlled Reversible Folding of Copolymers via Formation of β‐sheet Secondary Structures

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(10)

Published: Jan. 11, 2024

Protein functions are enabled by their perfectly arranged 3D structure, which is the result of a hierarchical intramolecular folding process. Sequence-defined polypeptide chains form locally ordered secondary structures (i.e., α-helix and β-sheet) through hydrogen bonding between backbone amides, shaping overall tertiary structure. To generate similarly complex macromolecular architectures based on synthetic materials, plethora strategies have been developed to induce control polymers. However, degree complexity structure-driving ensemble interactions demonstrated natural polymers unreached, as synthesizing long sequence-defined with functional backbones remains challenge. Herein, we report synthesis hybrid peptide-N,N-Dimethylacrylamide copolymers via radical Ring-Opening Polymerization (rROP) peptide containing macrocycles. The resulting contain regions β-sheet encoding amino acid sequences. Exploiting pH responsiveness embedded sequences, protonation or deprotonation in water induces self-assembly strands at an intramacromolecular level, driving polymer chain formation structures. We demonstrate that behavior sequence dependent reversible.

Language: Английский

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Visible light-induced photo-radical ring-opening copolymerization of thionolactone and acrylates

Polymer, Journal Year: 2024, Volume and Issue: 302, P. 127032 - 127032

Published: April 8, 2024

Radical ring-opening (co)polymerization (RROP) provides an accessible method for synthesizing main chain degradable vinyl polymers. Although the applications of reversible deactivation radical polymerization (RDRP) into RROP have been reported, use photo-mediated RDRP methods has received less attention than thermal process. Here, photo-RROP thionolactone dibenzo[c,e]-oxepine-5(7H)-thione (DOT) and methyl acrylate (MA) was studied using photo-iniferter (PI) addition-fragmentation(chain) transfer (RAFT) at ambient temperature without external initiators or photocatalysts. Despite occurrence some side reactions including desulfurization-oxygenation O-S isomerization DOT promoted by photoexcited thiocarbonyl groups, polymers with thioester linkages in backbone were prepared, which degraded presence amines bleach.

Language: Английский

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Addition–Fragmentation Ring‐Opening Polymerization of Bio‐Based Thiocarbonyl l‐Lactide for Dual Degradable Vinyl Copolymers

Macromolecular Rapid Communications, Journal Year: 2022, Volume and Issue: 44(2)

Published: Sept. 2, 2022

This study is designed to synthesize novel degradable polymers by radical addition-fragmentation ring-opening copolymerization of bio-based thiocarbonyl compounds with various vinyl monomers. Thiocarbonyl l-lactide capable acrylates and styrene via addition the carbon-sulfur double bonds followed as well controlled in conjunction reversible chain transfer (RAFT) process. The obtained possess ring-opened thioester ring-retained thioacetal functionalities backbone, both which could be cleaved under appropriate conditions different chemical stimuli.

Language: Английский

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Programming Photodegradability into Vinylic Polymers via Radical Ring‐Opening Polymerization

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(6)

Published: Dec. 20, 2022

Incorporation of photolabile moieties into the polymer backbone holds promise to remotely-control degradation. However, suitable synthetic avenues are limited, especially for radical polymerizations. Here we report a strategy program photodegradability vinylic polymers by exploiting wavelength selectivity photocycloadditions ring-opening polymerization (rROP). Irradiation coumarin terminated allylic sulfides with UVA light initiated intramolecular [2+2] photocycloaddition producing cyclic macromonomers. Subsequent RAFT-mediated rROP methyl acrylate yielded copolymers that inherited photoreactivity parent monomer. UVB efficient photocycloreversion dimers, causing degradation within minutes under or days sunlight exposure. Our may pave way insert linkages polymers, tuning specific wavelengths.

Language: Английский

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RAFT-Mediated 3D Printing of “Living” Materials with Tailored Hierarchical Porosity

ACS Applied Polymer Materials, Journal Year: 2022, Volume and Issue: 4(7), P. 4940 - 4948

Published: June 28, 2022

Applications of reversible addition–fragmentation chain-transfer (RAFT) polymerization in three-dimensional (3D) printing have recently expanded the scope light-based 3D technologies through manufacturing "living" materials. In this study, we report RAFT-mediated, computer-controlled layer-by-layer scaffolds with tailored hierarchical porosities and highly resolved micro- macroscale features. Our system offers precise control over internal external architectures porous materials, including pore size, which is not attainable using conventional techniques where achievable complexity fabricated limited. RAFT-mediated supports a variety structural designs enables open-porous materials controlled variation porosity (e.g., ranging from 23 to 70% porosity). The RAFT-based formulation also allowed original computer-aided design (CAD) models, were designed MATLAB and/or SolidWorks, showing well-defined features throughout continuous architecture. As an application example, triply periodic minimal surface (TPMS) structures 3D-printed digital light processing (DLP) printer. An additional advantage these that they show character so can be modified patterned post-manufacturing step reactivation dormant network-bound RAFT functionalities. This research further broadens RAFT-driven may implications molecular separation, catalysis, energy storage, tissue engineering, drug delivery.

Language: Английский

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