skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • A Breathing Atom‐Transfer Radical Polymerization: Fully Oxygen‐Tolerant Polymerization Inspired by Aerobic Respiration of Cells
Title: A Breathing Atom‐Transfer Radical Polymerization: Fully Oxygen‐Tolerant Polymerization Inspired by Aerobic Respiration of Cells
Abstract The first well‐controlled aqueous atom‐transfer radical polymerization (ATRP) conducted in the open air is reported. This air‐tolerant ATRP was enabled by the continuous conversion of oxygen to carbon dioxide catalyzed by glucose oxidase (GOx), in the presence of glucose and sodium pyruvate as sequential sacrificial substrates. Controlled polymerization using initiators for continuous activator regeneration (ICAR) ATRP of oligo(ethylene oxide) methyl ether methacrylate (OEOMA,Mn=500) yielded polymers with low dispersity (1.09≤Đ≤1.29) and molecular weights (MWs) close to theoretical values in the presence of pyruvate. Without added pyruvates, lower MWs were observed due to generation of new chains by H2O2formed by reaction of O2with GOx. Successful chain extension of POEOMA500macroinitiator with OEOMA300(Đ≤1.3) and Bovine Serum Albumin bioconjugates (Đ≤1.22) confirmed a well‐controlled polymerization. The reactions in the open air in larger scale (25 mL) were also successful.  more » « less
Award ID(s):
1707490
PAR ID:
10048955
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
57
Issue:
4
ISSN:
1433-7851
Page Range / eLocation ID:
p. 933-936
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; (, Angewandte Chemie International Edition)
    Abstract Atom transfer radical polymerization (ATRP) can be carried out in a flask completely open to air using a biocatalytic system composed of glucose oxidase (GOx) and horseradish peroxidase (HRP) with an active copper catalyst complex. Nanomolar concentrations of the enzymes and ppm amounts of Cu provided excellent control over the polymerization of oligo(ethylene oxide) methyl ether methacrylate (OEOMA500), generating polymers with high molecular weight (Mn>70 000) and low dispersities (1.13≤Đ≤1.27) in less than an hour. The continuous oxygen supply was necessary for the generation of radicals and polymer chain growth as demonstrated by temporal control and by inducing hypoxic conditions. In addition, the enzymatic cascade polymerization triggered by oxygen was used for a protein and DNA functionalized with initiators to form protein‐b‐POEOMA and DNA‐b‐POEOMA bioconjugates, respectively. 
    more » « less
  2. ; ; ; ; (, Journal of Polymer Science)
    Abstract Photoinduced initiators for continuous activator regeneration atom transfer radical polymerization (PICAR ATRP) using sodium pyruvate and blue light (λmax = 456 nm) is reported. Water‐soluble oligo(ethylene oxide) methyl ether methacrylate (OEOMA500) was polymerized under biologically relevant conditions. Polymerizations were conducted with 1000 ppm (with respect to the monomer) concentrations of CuBr2, tris(2‐pyridylmethyl)amine, and 1000 ppm or less FeCl3as a cocatalyst in water. Well‐defined polymers with up to 90% monomer conversion, high molecular weights (Mn > 190,000), and low dispersity (1.14 < Ð < 1.19) were synthesized in less than 60 min. The polymerization rate and dispersity were tuned by varying the concentration of sodium pyruvate (SP), iron, and supporting halide, as well as light intensity. The Cu/Fe dual catalysis provided oxygen tolerance enabling rapid, well‐controlled, aqueous PICAR ATRP of OEOMA500without deoxygenation. 
    more » « less
  3. ; ; ; ; (, Chemical Science)
    null (Ed.)
    ATRP (atom transfer radical polymerization) is one of the most robust reversible deactivation radical polymerization (RDRP) systems. However, the limited oxygen tolerance of conventional ATRP impedes its practical use in an ambient atmosphere. In this work, we developed a fully oxygen-tolerant PICAR (photoinduced initiators for continuous activator regeneration) ATRP process occurring in both water and organic solvents in an open reaction vessel. Continuous regeneration of the oxidized form of the copper catalyst with sodium pyruvate through UV excitation allowed the chemical removal of oxygen from the reaction mixture while maintaining a well-controlled polymerization of N -isopropylacrylamide (NIPAM) or methyl acrylate (MA) monomers. The polymerizations of NIPAM were conducted with 250 ppm (with respect to the monomer) or lower concentrations of CuBr 2 and a tris[2-(dimethylamino)ethyl]amine ligand. The polymers were synthesized to nearly quantitative monomer conversions (>99%), high molecular weights ( M n > 270 000), and low dispersities (1.16 < Đ < 1.44) in less than 30 min under biologically relevant conditions. The reported method provided a well-controlled ATRP ( Đ = 1.16) of MA in dimethyl sulfoxide despite oxygen diffusion from the atmosphere into the reaction system. 
    more » « less
  4. ; ; ; ; ; ; ; (, Angewandte Chemie International Edition)
    Abstract Hyperbranched polymethacrylates were synthesized by green‐light‐induced atom transfer radical polymerization (ATRP) under biologically relevant conditions in the open air. Sodium 2‐bromoacrylate (SBA) was prepared in situ from commercially available 2‐bromoacrylic acid and used as a water‐soluble inibramer to induce branching during the copolymerization of methacrylate monomers. As a result, well‐defined branched polymethacrylates were obtained in less than 30 min with predetermined molecular weights (36 000<Mn<170 000), tunable degree of branching, and low dispersity values (1.14≤Đ≤1.33). Moreover, the use of SBA inibramer enabled the synthesis of bioconjugates with a well‐controlled branched architecture. 
    more » « less
  5. ; ; ; ; ; (, Macromolecular Chemistry and Physics)
    Abstract The photoATRP of methyl acrylate (MA) is investigated using riboflavin (RF) and CuBr2/Me6TREN as a dual catalyst system under green LED irradiation (λ ≈ 525 nm). Both RF and CuBr2/Me6TREN enhanced oxygen tolerance, enabling effective ATRP in the presence of residual oxygen. High molar mass polymers (up toMn ≈ 129 000 g·mol−1) with low dispersity (Đ≤ 1.16) are prepared, and chain‐end fidelity is confirmed through successful chain extension. The molecular masses of the obtained polymer increased linearly with conversion and showed high initiation efficiency. Mechanistic studies by laser flash photolysis reveal that the predominant activator generation mechanism is reductive quenching of RF by Me6TREN (83%, under [CuBr2]/[Me6TREN] = 1/3 condition), supported by polymerization kinetics and thermodynamic calculations. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email