Enzymatic Cascade Catalysis for the Synthesis of Multiblock and Ultrahigh‐Molecular‐Weight Polymers with Oxygen Tolerance

Abstract

Synthesis of well-defined multiblock and ultrahigh-molecular-weight (UHMW) polymers has been a perceived challenge for reversible-deactivation radical polymerization (RDRP). An even more formidable task is to synthesize these extreme polymers in the presence of oxygen. A novel methodology involving enzymatic cascade catalysis is developed for the unprecedented synthesis of multiblock polymers in open vessels with direct exposure to air and UHMW polymers in closed vessels without prior degassing. The success of this methodology relies on the extraordinary deoxygenation capability of pyranose oxidase (P2Ox) and the mild yet efficient radical generation by horseradish peroxidase (HRP). The facile and green synthesis of multiblock and UHMW polymers using biorenewable enzymes under environmentally benign and scalable conditions provides a new pathway for developing advanced polymer materials.

A Breathing Atom‐Transfer Radical Polymerization: Fully Oxygen‐Tolerant Polymerization Inspired by Aerobic Respiration of Cells

“…[13,14] Thus,o xygen is the undesired radical scavenger in radical polymerizations.T oo vercome this,d eoxygenation with inert gasses,u se of ag love box or other techniques such as the freeze-pump-thaw method are used for effective removal of oxygen. [20,21] However,the generated hydrogen peroxide (from the glucose oxidase-catalyzed step between oxygen and d-glucose), [22][23][24] was not removed and its fate has not been addressed. [20,21] However,the generated hydrogen peroxide (from the glucose oxidase-catalyzed step between oxygen and d-glucose), [22][23][24] was not removed and its fate has not been addressed.…”

An Oxygen‐Tolerant PET‐RAFT Polymerization for Screening Structure–Activity Relationships

“…Many studies have shown that the multivalent presentation of ligands to soluble proteins and cell receptors is highly dependent on ligand density,spacing, and orientation. [6][7][8][9][10][11][12] There has therefore been growing interest in methods that will enable the high throughput synthesis and screening of well-defined polymers.Early works showed the possibility of using automatic synthesisers to conduct conventional controlled radical polymerisations (CRPs) in inert atmospheres, [13][14][15][16][17] but the recent development of various oxygen tolerant CRP mechanisms including singlet oxygen trapping, [18][19][20][21][22][23] enzyme degassing, [24][25][26][27][28][29] among others, [14,[30][31][32][33] have now been applied to the synthesis of polymer libraries in low volumes and open to the atmosphere. [34][35][36][37][38][39] These techniques have been used to prepare polymers with complex architectures such as arm first stars, [36,37] and block copolymers, [39] and have been applied to the investigation of polymerisationinduced self-assembly (PISA) systems.…”

Extending Designed Linear Biocatalytic Cascades for Organic Synthesis

“…Examples for the latter case are given here. For instance, a peroxidase catalyzed the formation of radicals which polymerized leading to well‐defined multiblock polymers in open vessels and Ultrahigh Molecular Weight Polymers (UMWP) in closed vessels (Scheme ) . The required hydrogen peroxide for the peroxidase was produced in a parallel reaction via oxidation of glucose by the oxidase P2Ox prior addition of the horseradish peroxidase (HRP).…”