Protein-polymer bioconjugates via a versatile oxygen tolerant photoinduced controlled radical polymerization approach

Abstract

The immense application potential of amphiphilic protein-polymer conjugates remains largely unexplored, as established "grafting from" synthetic protocols involve time-consuming, harsh and disruptive deoxygenation methods, while "grafting to" approaches result in low yields. Here we report an oxygen tolerant, photoinduced CRP approach which readily affords quantitative yields of protein-polymer conjugates within 2 h, avoiding damage to the secondary structure of the protein and providing easily accessible means to produce biomacromolecular assemblies. Importantly, our methodology is compatible with multiple proteins (e.g. BSA, HSA, GOx, beta-galactosidase) and monomer classes including acrylates, methacrylates, styrenics and acrylamides. The polymerizations are conveniently conducted in plastic syringes and in the absence of any additives or external deoxygenation procedures using low-organic content media and ppm levels of copper. The robustness of the protocol is further exemplified by its implementation under UV, blue light or even sunlight irradiation as well as in buffer, nanopure, tap or even sea water.

Fully oxygen-tolerant atom transfer radical polymerization triggered by sodium pyruvate

“…Photoirradiation of a copper catalyst in the presence of an electron donor in excess enables removal of dissolved oxygen. [42][43][44][45][46][47][48][49][50][51][52][53][54] Despite these great developments, the vast majority of reported methods are successful only when polymerization is performed in sealed vessels with a limited amount of oxygen in the reaction mixture. So far, only a few ATRP systems, mainly based on enzymatic degassing, can be carried out in a completely open reaction vessel, where oxygen continuously diffuses into the system from the atmosphere.…”

Mapping protein–polymer conformations in bioconjugates with atomic precision

“…However, a recent publication showed that proteins such as glucose-oxidase can be modified with polystyrene to the point of becoming globular nanoparticles, with improved or retained activity. 11 Recent work on surface-immobilization of enzymes has shown that lipase catalytic performance can be dramatically improved by attachment to hydrophilic surface-grafted polymers. 12 In a subsequent publication, by the same group, it was found that there is a trade-off in this system – more protein–polymer attachments resulted in higher stability but lower activity due to decreased motion in the folded state of the protein.…”

Aqueous copper-mediated reversible deactivation radical polymerization (RDRP) utilizing polyetheramine derived initiators

“…This is due to the fact that Cu-RDRP has been considered as one of the most robust strategies due to successful implementation under various conditions (e.g. in the presence of oxygen/air, [13][14][15] in various reaction media [16][17][18] ) and also due to the wide of range of materials that can be synthesized (i.e. polyacrylates, polymethacrylates, polystyrene, polyacrylamides) with excellent control over their (macro)molecular characteristics.…”

“…One of the main advantages of Cu-RDRP is its successful implementation in aqueous media, with excellent control over the macromolecular characteristics of the synthesized polymers. 15,18,19,21,30,31 In the presence of multidentate aliphatic amine ligands (e.g. tris [2-(dimethylamino)ethyl]amine, Me 6 TREN) and in aqueous media, Cu(I) is highly unstable towards rapid disproportionation, leading to Cu(II) and nascent, highly active Cu(0).…”