Researchers Develop New Antimicrobial Coating

Researchers Develop Novel Antimicrobial Coating A new coating has been developed to combat harmful and often antibiotic-resistant pathogens, designed to limit disease transmission and replace laborious cleaning processes on high-touch surfaces such as door handles and railings. Researchers from the University of Windsor (UWindsor) have developed and tested a composite material consisting of ionic (salt-based) liquids and copper nanoparticles that can coat surfaces and provide protection from microbes for much longer than traditional bleach-based cleaning. Dr. Abhinandan (Ronnie) Banerjee notes that this composite material is far superior to "someone trying to sterilize surfaces with bleach and a cloth." Banerjee and his colleagues in the Trant Team, a UWindsor research group focused on synthetic bioorganic materials, shifted their focus early in the COVID-19 pandemic to improve disinfection protocols, which typically involved frequent application of compounds such as bleach. The problem with conventional sanitization techniques is that this is not something done once. Keeping surfaces microbe-free requires either a dedicated worker or automation. Moreover, frequently wiping a surface can abrade the underlying material, creating even more opportunity for pathogen accumulation. The team developed a material that harnesses the natural antimicrobial properties of copper. They are now formulating a new material combination that will be easy to apply to surfaces and durable. Banerjee explained that copper nanoparticles are electrostatically attracted to pathogen cell walls and "weaken and break these walls, causing bacteria to die." The group's results were published in RSC Sustainability journal under the creative title "Lethal Weapon IL (Ionic Liquid)." A recently granted provisional patent gives Banerjee and the team time to find an industrial sponsor to help bring the microbial coating material to commercialization. Sima Dehghandokht, a UWindsor doctoral student who brought food microbiology expertise to the Trant group two years ago, said the material's potential applications extend beyond door handles, railings and elevator buttons to include hospitals, greenhouses, agricultural food production facilities and even "scientific laboratories where we constantly deal with pathogens and harmful bacteria. This could make life easier for scientists." The researcher also noted the importance of considering the harmful environmental effects, as antimicrobials like bleach require repeated application followed by product disposal. Both researchers acknowledge there are still questions to be answered about copper-based materials. Banerjee said determining exactly how long the coating remains effective is an important next step, as is investigating the antimicrobial effects of other nanoparticles such as zinc and iron, both of which are "literally very inexpensive." "We need to look at how modifying the properties of nanoparticles could impact the antimicrobial lifespan of the coating and also how we can kill more aggressive bacteria that cannot be easily killed by a simple wipe with bleach." Dehghandokht said, "We also need to test the toxicity of the compound to determine whether contact with the material will cause allergic reactions." Fortunately, the Trant Team has access to a 3D bioprinter capable of proliferating human skin cell arrays for further testing. Banerjee and Dehghandokht agree that access to CLS technology is critical to the development of antimicrobial coatings. Banerjee said, "We could not have done this work without the high-intensity light from CLS. We could see what happens to copper nanoparticles over time and how they release a charge that is toxic to bacteria. (CLS) became an integral part of this research."   Academic Reference: Abhinandan Banerjee et al, Lethal weapon IL: a nano-copper/tetraalkylphosphonium ionic liquid composite material with potent antibacterial activity, RSC Sustainability (2023). DOI: 10.1039/ D3SU00203A Source