Benchtop Preparation of Polymer Brushes by SI-PET-RAFT: The Effect of the Polymer Composition and Structure on Inhibition of a Pseudomonas Biofilm

Abstract

We report a high-throughput method for producing surface-tethered polymeric brushes on glass substrates via surface-initiated photoinduced electron transfer-reversible addition-fragmentation chain transfer polymerization (SI-PET-RAFT). Due to its excellent oxygen tolerance, SI-PET-RAFT allows brush growth using low reagent volumes (30 μL) without prior degassing. An initial 28 homopolymer brush library was successfully prepared and screened with respect to their antifouling performance. The high-throughput approach was further exploited to expand the library to encompass statistical, gradient, and block architectures to investigate the effect of monomer composition and distribution using two monomers of disparate performance. In this manner, the degree of attachment from Gram-negative Pseudomonas aeruginosa (PA) bacterial biofilms could be tuned between the bounds set by the homopolymer brushes.

Precision synthesis for well-defined linear and/or architecturally controlled thermoresponsive poly(N-substituted acrylamide)s

“…This progress has been made possible by improvements in synthetic methodologies. 51 In acrylamide polymerizations, polymerization systems using light-induced initiations 52 have been developed, which have further progressed when combined with the surface-initiated method 53 or heterogeneous polymerization techniques. 54,55 Covering the vast evolution of polymerization is impossible in a single review; instead, we summarize the precision polymerizations of specific kinds of N-alkylacrylamides (AMs) and N,N-dialkylacrylamides (DAs) and their outcomes, focusing on the reversible-deactivation radical polymerizations (RDRPs) 51 of AMs and DAs and the organocatalytic group transfer polymerization (GTP) 56,57 of DAs.…”

Surface-Immobilized Photoinitiators for Light Induced Polymerization and Coupling Reactions

“…First, a very low amount of PC is needed (ppm range) and the polymerization can be carried out in the presence of molecular oxygen, which provides the possibility to translate polymerization processes from controlled environments such as gloveboxes to the benchtop. Commonly used PCs which have been reported in the literature are transition-metal complex photocatalysts (for example, fac-Ir(ppy) 3 , Ru(bpy) 3 Cl 2 , ZnTPP), eosin Y, porphyrines and metal oxides [ 12 , 156 , 159 ]. Since the pioneering work referred to PET-RAFT in 2014, the interaction between an excited state PC and the RAFT agent remains uncertain and challenging.…”

“…Because of the lower experimental effort, which results from the oxygen tolerance of SI-PET-RAFT (absence of inert gas, vacuum, etc. ), the authors pointed out that this benchtop methodology provides a high throughput approach for the identification and evaluation of polymer brush structure-property-performance relationships [ 12 ]. One year later the same group prepared a polymer brush with antifouling and visible light triggered bactericidal properties, on circular glass substrate using the same bifunctional RAFT agent ( Figure 14 A) [ 161 ].…”

“…The large number of achievements in light mediated polymerization techniques also demonstrates their relevance for practical applications. For example, oxygen tolerance allows for a reduction of experimental effort since the process can be translated from inert-atmosphere to ambient conditions, thereby reducing cost and allowing for the implementation in high-throughput screenings [ 12 ]. Density functional theory (DFT) is a powerful tool to unveil detailed mechanisms, as it has been used exemplarily for the decarboxylation mechanism of a thioxanthone chromophore upon light irradiation [ 13 ].…”

Design of biointerfaces composed of soft materials using controlled radical polymerizations

“…6(j)). 144,146 These characteristics allow for high-throughput investigations of material properties. Nagao and co-workers reported a facile and fast screening of a synthetic glycopolymer library using PET RAFT polymerization.…”