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[Display omitted] • Durable superhydrophobic nanodiamond based coating for stainless-steel. • Water contact angle of 156.3 ± 1.9° with 2.3 ± 0.5° contact angle hysteresis. • Surfaces characterized with SEM, AFM, and ATR-FTIR. • 2.3 ± 0.6 log 10 & 2.0 ± 0.9 log 10 reductions in E. coli & L. innocua , respectively. • Resisted fouling from contaminated Romaine lettuce leaves. Increasing concerns revolve around bacterial cross-contamination of leafy green vegetables via food-contact surfaces. Given that stainless-steel is among the commonly used food-contact surfaces, this study reports a coating strategy enhancing its hygiene and microbiological safety through an antifouling approach via superhydrophobicity. The developed method involves growing a nickel-nanodiamond nanocomposite film on 304 stainless-steel via electroplating and sequential functionalization of the outer surface layer with nonpolar organosilane molecules via polydopamine moieties. The resultant superhydrophobic stainless-steel surfaces had a static water contact angle of 156.3 ± 1.9° with only 2.3 ± 0.5° contact angle hysteresis. Application of the coating to stainless-steel was demonstrated to yield 2.3 ± 0.6 log 10 and 2.0 ± 0.9 log 10 reductions in the number of adherent gram-negative Escherichia coli O157:H7 and gram-positive Listeria innocua cells, respectively. These population reductions were shown to be statistically significant (α = 0.05). Coated stainless-steel also resisted fouling when contacted with contaminated romaine lettuce leaves and maintained significant non-wetting character when abraded with sand or contacted with high concentration surfactant solutions. The incorporation of superhydrophobic stainless-steel surfaces into food processing equipment used for washing and packaging leafy green vegetables has the potential to mitigate the transmission of pathogenic bacteria within food production facilities. [ABSTRACT FROM AUTHOR]

Foodborne illness outbreaks caused by bacterial pathogens may take place on a large scale and result in millions of hospitalizations and thousands of deaths every year throughout the world. One key strategy for dealing with this global issue is the design of smart surfaces and coatings which inhibit and reduce bacterial attachment. This can mitigate contamination and cross-contamination during farm-to-table food processing, promoting food safety, and hygiene. Herein, we reported a durable superhydrophobic coating on aluminum surfaces fabricated by sequential deposition of ultrahard nanodiamond, self-assembly of l-3,4-dihydroxyphenylalanine (l -dopamine), and chemical modification with an organoflurosilane. This coating achieved static, advancing, and receding water contact angles of 159.0 ± 2.5°,154.0 ± 2.4°; and 153.7 ± 1.7°, respectively, representing water super-repellency with a low overall root mean square (rms) roughness of 173.5 ± 69.6 nm. In comparison to the bare, unmodified aluminum, the coated aluminum surfaces prevented the attachment of 99.5% of applied Escherichia coli O157:H7 (E.coli O157:H7) and 99.0% of Staphylococcus aureus (S. aureus) cells. In addition, due to the presence of nanodiamond building blocks, the coated surfaces demonstrated a high mechanical resistance against scratching and endured at least 10,000 shearing/rubbing cycles with a nylon surface. Overall, we anticipate that implementation of this coating could improve safety and hygiene of food-contact surfaces that require harsher mechanical operational conditions. • Development of biocompatible nanodiamond-based superhydrophobic coating on aluminum surfaces. • Attachment of Escherichia coli O157:H7 and Staphylococcus aureus was reduced by >99.0%. • Superhydrophobic aluminum surfaces exhibited excellent mechanical resistance against polymer scratching. • Bacterial antiadhesion properties are based on the minimized contact area and weak intermolecular interactions. • The proposed superhydrophobic coating can be applied on metal food-contact surfaces. [ABSTRACT FROM AUTHOR]

The demand for hip arthroplasties and other joint replacement orthopedic surgeries is on the rise. Combined with the emergence of antibiotic drug resistant strains of pathogenic bacteria, there is an increasing need for the development of bacterial antifouling surface treatment technologies which can be applied to titanium alloy medical devices. Herein is reported the development of a durable, fluorine-free superhydrophobic surface treatment for Ti6Al4V, fabricated through facile means without the use of HF or fluoropolymers, utilizing safe reagents under mild reaction conditions. Nanoscale texturing was created with an alkaline hydrothermal process. An alkyl surface chemistry was imparted via the deposition of an alkyl self-assembled monolayer to achieve superhydrophobic, non-wetting behavior. This superhydrophobic surface is capable of imposing 1.55 ± 0.13 and 1.72 ± 0.23 log 10 reductions in the adherent populations of Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Pseudomonas aeruginosa (P. aeruginosa) bacteria, respectively. This represents a safe route to a significant potential mitigation in the costs and dangers arising from medical device associated infections. [Display omitted] • Titanium alloy implant devices are prone to perioperative bacterial infection. • Superhydrophobic titanium surfaces are readily prepared without dangerous fluorine. • Modified, durable surfaces resist attachment of pathogenic bacterial species. [ABSTRACT FROM AUTHOR]