Enzymatically Degassed Surface-Initiated Atom Transfer Radical Polymerization with Real-Time Monitoring

Abstract

Polymer brush coatings are frequently prepared by radical polymerization, a notoriously oxygen sensitive process. Glucose oxidase (GOx) can inexpensively enable radical polymerization in solution by enzymatically consuming oxygen as it oxidizes glucose. Here, we report the growth of polymeric brushes using GOx-assisted atom transfer radical polymerization (ATRP) from a surface while open to air. Specifically, we grew a set of biomedically relevant polymer brushes, including poly­(oligo­(ethylene glycol) methacrylate) (POEGMA), poly­(2-dimethylaminoethyl methacrylate) (PDMAEMA), poly­(sulfobetaine methacrylate) (PSBMA), and poly­(2-(methylsulfinyl)­ethyl acrylate (PMSEA). For each of these polymers, we monitored GOx-assisted and GOx-free ATRP reaction kinetics in real time using quartz crystal microbalance (QCM) and verified findings with localized surface plasmon resonance (LSPR). We modeled brush growth kinetics considering bimolecular termination. This model fit our data well (r 2 > 0.987 for all samples) and shows the addition of GOx increased effective kinetic chain lengths, propagation rates, and reproducibility. We tested the antifouling properties of the polymer brush coatings against human blood plasma and were surprised to find that coatings prepared with GOx repelled more plasma proteins in all cases than their GOx-free counterparts.

Surface‐initiated PET‐RAFT polymerization under metal‐free and ambient conditions using enzyme degassing

“…Several attractive features of this approach include low cost, efficient enzymatic activity in the presence of organic solvents, and exceedingly mild polymerization conditions. Extension of this system in combination with Cu‐mediated ATRP to SI‐CRP was recently reported by Zauscher and coworkers, while ATRP and RAFT systems based on select photocatalysts have been used to achieve oxygen tolerance for polymer brush synthesis . Inspired by these studies, we hypothesized that surface‐initiated PET‐RAFT in the presence of GOx would enable efficient polymer brush growth under open‐to‐air environments via a conventional PET‐RAFT mechanism.…”

Lactone monomers obtained by enzyme catalysis and their use in reversible thermoresponsive networks

“…Recently, biocatalysis for polymer applications has attracted increasing interest . Biocatalytic routes for production of monomers have been reported, as highlighted for cyclic lactones and their corresponding ketone precursors in Table .…”

Biocatalytic Hybrid Nanoparticles for Degassing and Stabilization of Single Electron Transfer-Living Radical Polymerization in Pickering emulsions

“…hydrazine), [10] [11] thus hampering the scale-up and transition from academia to industry of these controlled polymerization processes. To overcome this issue, notable works from the groups of Stevens [12][13][14] and Matyjaszweski, [15][16][17] among others [18][19][20][21] reported the use of oxidoreductase enzymes to deplete oxygen, thus giving rise to enzyme-degassed RDRP techniques.…”

“…[12] [13] So far, most of these systems have been applied in RAFT and ATRP of water-soluble monomers in aqueous media to retain the enzyme activity. [16][17][18][19][20] The polymerization of hydrophobic monomers remains scarcely explored, and is hitherto limited to ATRPmediated miniemulsion processes using soluble ionic surfactants such as dodecyl sulfate (SDS), [17] which could disrupt the activity of the enzyme at longer reactions times. [22] Indeed, some of these previous reported systems require the addition of sacri cial substrates (e.g.…”