Zinc
https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/#h2
Copper
https://ods.od.nih.gov/factsheets/Copper-HealthProfessional/
"Zinc and copper need to be supplemented in combination with each other (ratio 10: 1)."
https://thehealthfactory.com/w/en/nano-minerals/
"Brass is an alloy of copper and zinc"
https://en.wikipedia.org/wiki/Brass
"Colloidal nanoparticles are being intensely pursued in current nanoscience research."
https://pubs.acs.org/doi/10.1021/acs.chemrev.5b00703
"The role of nanotechnology is highly relevant to counter this “virus” nano enemy."
https://pubs.acs.org/doi/10.1021/acsnano.0c04006
"Zinc promotes immune functions and helps people resist infectious diseases"
https://www.cdc.gov/nutrition/micronutrient-malnutrition/micronutrients/index.html
"Zinc (Zn), an essential micronutrient for key cellular activity such as cell growth, differentiation, and survival.
Commonly recognized as an NMDA-antagonist for mental health and testosterone booster, zinc deficiency suppresses our adaptive and innate immune response.
Zinc interferes with the replication of the SARS-CoV-2 virus replication."
https://medium.com/optimizebetter/blocking-viruses-with-zinc-and-zinc-ionophores-hydroxychloroquine-and-zinc-40693abed472
"But how does copper inactivate viruses? Copper destroys the replication and propagation abilities of viruses, such as SARS-CoV-2, influenza, and other respiratory viruses."
https://www.news-medical.net/news/20210105/Copper-surfaces-can-inactivate-SARS-CoV-2-in-as-little-as-one-minute-study-finds.aspx
"Copper can eliminate pathogenic organisms such as coronavirus bacterial strains, influenza virus, HIV, and fungi after a short period of exposure."
https://pubmed.ncbi.nlm.nih.gov/33069048/
"The U.S. Environmental Protection Agency (EPA) announced recently that certain copper alloys provide effective long-term protection against viruses, including SARS-CoV-2, which causes COVID-19."
https://www.prnewswire.com/news-releases/copper-surfaces-provide-continuous-protection-against-sars-cov-2-301228334.html
"Nanomaterials are used in a variety of FDA-regulated products because of their unique properties, imparting potential advantages to products considered for development. Such materials, due to their nanoscale size, can have chemical, physical, and biological properties that differ from those of their larger counterparts."
https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-safety-nanomaterials-cosmetic-products
"Nanotechnology is an emerging technology that has the potential for use in a broad array of FDA-regulated products, including medical products, foods and cosmetics. Nanomaterials, developed using nanotechnology, are measured in nanometers — equal to about one-billionth of a meter — so small that they cannot be seen with a regular microscope. These nanomaterials can have different chemical, physical, or biological properties than their conventionally-scaled counterpart materials used in many products regulated by FDA."
https://www.fda.gov/science-research/nanotechnology-programs-fda/nanotechnology-fact-sheet
"FDA’s nanotechnology regulatory science research portfolio focuses on understanding interactions of nanomaterials with biological systems; and on the adequacy of testing approaches for assessing safety, effectiveness, and quality of products containing nanomaterials."
https://www.fda.gov/science-research/nanotechnology-programs-fda/nanotechnology-fact-sheet
Alternative Antimicrobial Approach: Nano-Antimicrobial Materials
https://www.hindawi.com/journals/ecam/2015/246012/