Inhibition of bacterial adhesion and biofilm formation on zwitterionic surfaces

Abstract

In this work, we report a study of long-chain zwitterionic poly(sulfobetaine methacrylate) (pSBMA) surfaces grafted via atom transfer radical polymerization (ATRP) for their resistance to bacterial adhesion and biofilm formation. Previously, we demonstrated that p(SBMA) is highly resistant to nonspecific protein adsorption. Poly(oligo(ethylene glycol) methyl ether methacrylate) (pOEGMA) grafted surfaces were also studied for comparison. Furthermore, we quantify how surface grafting methods will affect the long-term biological performance of the surface coatings. Thus, self-assembled monolayers (SAMs) of alkanethiols with shorter-chain oligo(ethylene glycol) (OEG) and mixed SO 3 − /N + (CH 3 ) 3 terminated groups were prepared on gold surfaces. The short-term adhesion (3 h) and the long-term accumulation (24 h or 48 h) of two bacterial species (Gram-positive Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa) on these surfaces were studied using a laminar flow chamber. Methyl (CH 3 ) SAM on gold and a bare glass were chosen as references. p(SBMA) reduced short-term adhesion of S. epidermidis and P. aeruginosa relative to glass by 92% and 96%, respectively. For long-term biofilm formation, qualitative images showed that p(SBMA) dramatically reduced biofilm formation of S. epidermidis and P. aeruginosa as compared to glass.

Combinatorial discovery of polymers resistant to bacterial attachment

“…Comparison with the performance of our hits to these literature reports is difficult as experimental methodologies vary widely. Attachment of P. aeruginosa (PA01) after 3 h incubation on a poly(sulfobetaine methacrylate)-grafted surface has been reported to be lower by 25-fold compared to that on glass 19 , and in an incubation time closer to ours, a poly(carboxybetaine methacrylate)-grafted surface had 11-fold lower attachment of P. aeruginosa after 96-h bacterial exposure compared to glass 18 .…”

“…There are several other different strategies that can be found in the literature to reduce bacterial attachment to surfaces that are not yet commercially available; for example, zwitterionic coatings function by preventing attachment 18,19 . Comparison with the performance of our hits to these literature reports is difficult as experimental methodologies vary widely.…”

“…These approaches aim to kill bacterial cells that attach to a material, but we believe that greater efficacy in preventing biofilm formation might be achieved by the development of new materials that are inherently resistant to biofilm formation 16 . Previous attempts to use an anti-attachment strategy include poly(ethylene glycol) brushes 17 and zwitterionic polymers 18,19 . An important problem that has restricted the development of materials resistant to bacterial attachment and growth is the poor understanding of the interactions that bacteria make with surfaces, which is required for ab initio materials design.…”

Surface Sensing and Settlement Strategies of Marine Biofouling Organisms

“…However, the degradation of the ethylene-glycol-containing chemistries makes them unsuitable for long-term antifouling applications [34,35]. Other promising approaches involve the use of amphiphilic [26,27,29,36] or zwitterionic chemistries [37][38][39][40]. Even though fouling inhibition is the most desirable way of avoiding biofouling, the development of such inert, non-toxic, and long-term stable coatings remains to be the most challenging of the three approaches.…”

The impact of material properties, nutrient load and shear stress on biofouling in food industries

“…was observed that for 80% of the successfully predicted cases, the impact of the tested variables at 0.5 h (initial adhesion) was further amplified during the biofilm maturation phase (after 6 h). Different studies have shown that lower initial cell adhesion leads to lower amount of biofilm (Cheng et al, 2007;Godoy-Gallardo et al, 2014) whereas others report that these initial events are not always important for biofilm maturation (Bernstein et al, 2014;Cerca et al, 2005).…”