Ultra-low volume oxygen tolerant photoinduced Cu-RDRP

Abstract

We introduce the first oxygen tolerant ultra-low volume (as low as 5 μL) photoinduced Cu-RDRP of a range of hydrophobic, hydrophilic and semi-fluorinated monomers.

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

“…In the absence of either catalyst (copper/ligand) or BSA-Br macroinitiator no polymerization was detected by SEC or PAGE and the lack of polymerization was also evident in the dark ( Supplementary Fig. 14 mediate the reduction of the copper complex 47 , addition of the complex caused a slight pH increase, though the final pH (7.66) did not affect protein stability. In agreement with our initial hypothesis, when a stoichiometric amount of ligand was used (1/1 Cu II /L), the polymerization did not start verifying the necessity to utilize excess of the ligand ( Supplementary Table 1, Entry 17, Supplementary Fig.…”

“…Upon judiciously optimizing the polymerization conditions, a ratio of M n /I o /Cu II /L = 5000/1/1.5/12 was selected and all reagents were carefully loaded in a plastic syringe, which was subsequently exposed to UV irradiation (broad band~365 nm, 36 Watt). The excess of the ligand Tris[2-(dimethylamino)ethyl]amine (Me 6 T-REN) with respect to copper is essential for the in situ reduction of CuBr 2 to CuBr as previously reported 47,56 . Initially, a minor amount of organic solvent (DMSO,~5%) was added to the buffer solution as this would allow efficient emulsification for cases where the monomer is solid rather than liquid (total organic content (OC) = 18%).…”

“…Nonetheless, the use of conventional CRP (Controlled Radical Polymerization, also referred to as RDRP, Reversible Deactivation Radical Polymerization) systems necessitates deoxygenation that is typically achieved via high-cost, time-demanding processes such as freeze-pump-thaw and/or inert gas sparging, which require sophisticated equipment and can potentially cause protein denaturation or loss of enzymatic activity 6,[36][37][38] . Recently, seminal work by the groups of Boyer 39,40 , Matyjaszewski [41][42][43] and others [44][45][46][47] led to elegant approaches in which no external deoxygenation is required for the synthesis of well-defined polymers. Such systems typically employ enzymes (e.g., glucose oxidase) [48][49][50] , sacrificial substrates 43 , and/or increased concentrations of photocatalysts or reducing agents [51][52][53] to in situ consume oxygen prior to polymerization.…”

“…1). Inspired by recent oxygen tolerant copper-mediated polymerization strategies 46,47 , we present a photoinduced polymerization process, which eliminates the need for deoxygenation and provides a universal approach for the synthesis of protein-polymer bioconjugates from protein macroinitiators. Our methodology avoids damage to the secondary structure of the protein, is compatible with various proteins (e.g., BSA, HSA, GOx, beta-galactosidase) and monomer classes including acrylates, methacrylates, styrene derivatives, and acrylamides.…”

Tuning Dispersity by Photoinduced Atom Transfer Radical Polymerisation: Monomodal Distributions with ppm Copper Concentration

“…Next, given the recent interest in oxygen-tolerant polymerisations, [39][40][41] we also wanted to perform an identical polymerisation in the absence of any external deoxygenation procedures while also using ppm levels of catalyst. Pleasingly, by decreasing the catalyst loading, broad and monomodal molecular weight distributions were obtained which further highlights the robustness of our approach ( Figure S11).…”