Nanostructured Surfaces that Show Antimicrobial, Anticorrosive, and Antibiofilm Properties

Abstract

Provided in this article are the quantitative and qualitative morphological results describing the action of several nanostructured surfaces for bactericidal and bacteriostatic action. Results are also provided to illustrate microbial corrosion and its impact. Biofilm formation is correlated to colony formation. Nanostructured surfaces, i.e. surfaces with welded nanoparticles are noted to display biocidal activity with varying efficacies. Porous nanostructures, on stainless steel and copper substrates, made of high purity Ag, Ti, Al, Cu, MoSi2, and carbon nanotubes, are tested for their efficacy against bacterial colony formation for both gram-negative, and gram-positive bacteria. Silver and Molybdenum disilicide (MoSi2) nanostructures are found to be the most effective bactericidal agents with MoSi2 being particularly effective in both low and high humidity conditions. Bacteriostatic activity is also noted. The nanostructured surfaces are tested by controlled exposures to several microbial species including (Gram+ve) bacteria such as Bacillus Cereus and (Gram-ve) bacteria such as Enterobacter Aerogenes. The resistance to simultaneous exposure from diverse bacterial species including Arthrobacter Globiformis, Bacillus Megaterium, and Cupriavidus Necator is also studied. The nanostructured surfaces were found to eliminates or delay bacterial colony formation, even with short exposure times, and even after simulated surface abrasion. The virgin 316 stainless steel and copper substrates, i.e. without the nanostructure, always displayed rapid bacterial colony evolution indicating the lack of antimicrobial action. The efficacy of the nanostructured surface against colony formation (bacterial recovery) for E-Coli (two strains) and virus Phi 6 Bacteriophage with a host Pseudomonas Syringae was also studied. Preliminary results are presented that also show possible anti-fungal properties by the nanostructured MoSi2. When comparing antimicrobial efficacy of flat polished surfaces (no curvature or nanostructure) with nanostructure containing surfaces (high curvature) of the same chemistry, shows that bacterial action results from both the nanostructure size and chemistry.

Access to thermally robust and abrasion resistant antimicrobial plastics: synthesis of UV-curable phosphonium small molecule coatings and extrudable additives

“…19,22,23 While these immobilized cationic surface coatings have exceptional antimicrobial capacities, few possess this property in conjunction with substantial durability to abrasion and other stressors, highlighting a limitation of these coatings. [24][25][26][27] Harney and coworkers carried out exploratory studies using tuneable amphiphilic ammonium antimicrobials as solution blended additives in polyurethane. 28 This methodology can yield antimicrobial additives that are surface proximate or more evenly blended in the sample depending on the amphiphobic nature of the cation.…”

Surface modification strategies for hemodialysis catheters to prevent catheter‐related infections: A review

“…International standards, such as, ISO 22196/JIS (Japanese Industrial Standard) Z 2801 or ASTM E 2149, ASTM E 2180 are often used for testing the antimicrobial properties of materials and products. Although all these techniques are classified under quantitative antibacterial testing approaches and used for testing of antibacterial hemodialysis catheters, their working principles are different 47 . The principle of ASTM E2149—Test for Irregularly Shaped Antimicrobial Surfaces, is based on the immersion of the material into the suspension of bacteria with known initial concentration at different time points between 1 and 24 hr.…”

“…Antibiotic resistance may occur naturally as a result of structural and functional inheritance in microorganisms, and it may also be obtained from other bacteria by uptake of resistance gene via plasmids and transposons. 43 According to data from the National Institute of Health (NIH), 47 The principle of ASTM E2149-Test for Irregularly Shaped Antimicrobial Surfaces, is based on the immersion of the material into the suspension of bacteria with known initial concentration at different time points between 1 and 24 hr. The bacteria concentration in the solution at certain intervals is compared with the reference concentration and it is decided to be antibacterial if there is a significant decrease.…”

Hybrid Materials Based on Multi-walled Carbon Nanotubes with Antimicrobial Properties

“…The antimicrobial activity of silver ions is higher in case of Gram negative bacteria (e.g. E. coli) [22]. It is widely believed that the effectiveness of Ag + as an antibacterial is due to its ability to bind with thiol (-SH) groups on proteins and enzymes; Silver ions prevent DNA replication and affect the structure and permeability of the cell membrane and have also been shown to interact with DNA to enhance pyrimidine dimerization by the photodynamic reaction and possibly prevent DNA replication [23][24][25][26].…”