Reduced bacterial colonisation on surfaces coated with silicone nanostructures

Abstract

Bacterial adhesion on silicone nano-and microstructures is investigated in stagnant and flow experiments. Static adhesion tests are performed in 0.9% NaCl solution. These experiments reveal that the number of Staphylococcus epidermidis (S. epidermidis) and Escherichia coli (E. coli) adhering to glass surfaces can significantly be reduced if silicone nanofilament and rod coatings are present. Further, flow experiments are conducted in a parallel-plate flow chamber using 0.9% NaCl solution and artificial urine as medium. Silicone nanofilament coated surfaces are compared to uncoated glass surfaces. E. coli colonisation on filament coated surfaces is reduced for at least 24 h in 0.9% NaCl solution, while in artificial urine no reduction is observed after 24 h. S. epidermidis shows converse adhesion behaviour. Here, initial adhesion on nanofilaments is promoted but the number of adherent S. epidermidis seems to decrease after extended contact time. The obtained results demonstrate that superhydrophobic silicone surfaces significantly reduce bacterial colonisation under stagnant and dynamic conditions. However, the bacterial adhesion behaviour depends on the architecture of the silicone nano-and microstructures and the bacterial species investigated.

Bactericidal efficiency of micro- and nanostructured surfaces: a critical perspective

“…For the viability experiment, a common step is to rinse the substrates to remove non-adhered or weakly-adhered bacteria from the surface before conducting quantication test such as live dead analysis or colony counting. 31,33,37,38,40,45,47,51,53,55,56,59,63,[66][67][68][69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84][85] Commonly used rinsing methods are summarised in Table 1. Strikingly, the volumes or owrates used in the rinsing step of these studies are unspeci-ed, and the effect of stresses exerted on the loosely attached bacterial cells have not been accounted for.…”

Tunable Superhydrophobic Aluminum Surfaces with Anti-Biofouling and Antibacterial Properties

“…Bacterial cell density was determined by measuring the optical density (OD) at 625 nm wavelength. Static bacterial adhesion experiments were conducted following a prescribed protocol elsewhere [17]. Briefly, two 250 mL sterile beakers were filled with 99 mL 10 mM phosphate buffer solution (PBS) (pH 7.5 +/− 0.3 at 25 • C.) and 1 mL bacterial culture.…”

Micro‐ and Nanotexturization of Liquid Silicone Rubber Surfaces by Injection Molding Using Hybrid Polymer Inlays

“…This material is of great interest to the medical industry due to its biocompatibility. [10,11] These medical applications have interesting synergies with surface texturing, since pieces with antibacterial properties, [12] cell alignment, [13,14] and high wettability [15] can be obtained. Therefore, it is interesting to investigate methods that allow the mass production of the pieces with surface textures.…”