Fabrication of Robust Superhydrophobic Coatings onto High-Density Polyethylene Food Contact Surfaces for Enhanced Microbiological Food Safety

Abstract

Lack of maintenance and poor sanitation of food-contact surfaces (FCSs) can result in foodborne microbial contamination and biofilm formation. With increasing industrial concerns over food safety and hygiene, it is important to keep FCSs bacteria-free to protect the consumers from various foodborne illnesses. In the current study, we report the fabrication of highly durable nanodiamond (ND) based coatings on high-density polyethylene (HDPE), combining the chemisorption of low surface energy ligands and rigid nanotexturing. The coated HDPE surfaces resulted in static, advancing, and receding water contact angles of 151.1 ± 0.3°, 155.0 ± 1.0°, and 151.0 ± 1.9°, respectively. This superhydrophobic coating demonstrated excellent mechanical durability, retaining its highly water-repellent nature after surface abrasion with spinach leaves and onion peels, as well as after 50 cycles of sand abrasion. In comparison to bare HDPE, the adhesion of Salmonella typhimurium LT2 and Listeria innocua bacteria onto the coated surfaces was reduced by 2.1 ± 0.43 (>99.34%) and 1.6 ± 0.55 (>97.75%) log-cycles, respectively. In addition, the coated substrates successfully reduced the cross-contamination of spinach leaves by S. typhimurium LT2 and L. innocua. Overall, this study demonstrates the proof-of-concept that durable superhydrophobic coatings involving nanodiamond on HDPE have the potential to reduce bacterial cross-contamination scenarios of FCSs in food processing environments.

Bioinspired Superhydrophobic Nanocoating Based on Polydopamine and Nanodiamonds to Mitigate Bacterial Attachment to Polyvinyl Chloride Surfaces in Food Industry Environments

“…This process greatly diminishes VdW attractions while promoting ES repulsion between negatively charged bacterial species and alkyl silane . Additionally, the preferential adhesion of planktonic cells to nutrient-rich lettuce leaves over abiotic superhydrophobic PVC could also significantly contribute to the reduction in adhesion of both Gram-positive and Gram-negative bacterial species …”

“…125 Additionally, the preferential adhesion of planktonic cells to nutrient-rich lettuce leaves over abiotic superhydrophobic PVC could also significantly contribute to the reduction in adhesion of both Gram-positive and Gram-negative bacterial species. 126…”

Edible nano-encapsulated cinnamon essential oil hybrid wax coatings for enhancing apple safety against food borne pathogens

“…The freeze-dried nanoparticle powder was characterized using SEM (Tescan LYRA-3 Model GMH) under high-resolution mode at 93.3 k × . Prior to image characterization, the nanoparticle powders were coated with Pt/Pd (5 nm thickness) using a sputter coater (Cressington 208HR, Cressington Scientific Instruments, Watford, UK) to enhance the conductivity of the samples and reduce charging ( Arcot et al, 2021 ; Liu et al, 2021 ).…”