Escherichia coli Adhesion and Biofilm Formation on Polydimethylsiloxane are Independent of Substrate Stiffness

Abstract

Bacterial adhesion and biofilm formation on the surface of biomedical devices is a detrimental process that compromises patient safety and material functionality. Several physicochemical factors are involved in biofilm growth, including the surface properties. Among those, material stiffness has recently been suggested to influence microbial adhesion and biofilm growth in a variety of polymers and hydrogels. However, no clear consensus exists about the role of material stiffness on biofilm initiation and whether very compliant substrates are deleterious to bacterial cell adhesion. Here, by systematically tuning substrate topography and stiffness while keeping the surface free energy of polydimethylsiloxane substrates constant, we show that topographical patterns at the micron and submicron scale impart unique properties to the surface that are independent of the material stiffness. The current work provides a better understanding of the role of material stiffness on bacterial physiology and may constitute a cost-effective and simple strategy to reduce bacterial attachment and biofilm growth even in very compliant and hydrophobic polymers.

Implication of Surface Properties, Bacterial Motility, and Hydrodynamic Conditions on Bacterial Surface Sensing and Their Initial Adhesion

“…The wrinkled topography on PDMS surfaces significantly reduced both E. coli adhesion and the overall biofilm biomass, regardless of material stiffness. This result suggests that topographical patterns of surfaces may render surface stiffness negligible regarding bacterial adhesion and biofilm accumulation (Arias et al, 2020). Another example of the interdependence of surface parameters that affect bacterial adhesion can be found in a recent study by Yuan et al (2017).…”

“…As discussed earlier, surface stiffness and topography are the factors interdependently affecting bacterial adhesion. Interestingly, Arias et al (2020) found that E. coli tend to adhere on PDMS surfaces with variable stiffness in a different pattern when surface topography was introduced to the surface. The wrinkled topography on PDMS surfaces significantly reduced both E. coli adhesion and the overall biofilm biomass, regardless of material stiffness.…”

Adaptive Coatings with Anticorrosion and Antibiofouling Properties

“…The inhibition of gram-negative bacterial adhesion to PH coating was relatively close to the inhibition of bacterial adhesion to others antifouling materials (≈48-58%). [111][112][113] Antifouling materials containing silver nanoparticles (3.5 wt%) [114] or amphiphilic coating with low surface energy (≈20 mJ m −2 ) [115] displayed a larger inhibition of bacterial adhesion (≈88-90%) but did not possessed an anticorrosion property.…”

Bacterial envelope damage inflicted by bioinspired nanospikes grown in a hydrogel

“…Formalinfixed E. coli seeded on wrinkled polydimethylsiloxane (PDMS) was imaged with a PNP-TR cantilever in contact mode in PBS using a force of 20 pN, and subsequently indented with a trigger force of 2 nN following a procedure as described previously. Wrinkled PDMS was obtained as described by Arias and coworkers 56 . Determination of the nanoprobes' radius was performed using a calibration grid (Silicon grating TGT01, NT-MDT Spectrum Instruments) ( Supplementary Figures S5 and S6).…”