June ended with the news of Asia’s richest man, Gautam Adani, raising $775 million to build India’s largest copper refinery in Kutch, Gujarat. Adani sure knows the potential of copper, the pinkish-orange metal that has been the doctor’s favourite in the Periodic Table. Copper has always been hailed for its anti-bacterial and anti-viral properties. Now, Japanese researcher Jae Joon Kim from the University of Tokyo has masterminded a copper nanomesh, replicating a soft wearable fabric, which kills bacteria and viruses almost in an instant.
Jae’s research was published last month in the Proceedings of the National Academy of Sciences. He reported that copper kills microbes quickly, annihilating 99.99 per cent of bacteria within one minute and 99.99 per cent of viruses within 10 minutes. The wearable antimicrobial copper nanomesh that Jae has conceived sticks to human skin with just a touch of water. The material is so soft and stretchy that at three microns thick, the mesh is 20 times thinner than the diameter of the average human hair. Three microns is as thick as a spider web. Because it’s so thin, the nanomesh preserves the skin’s natural sense of touch, temperature and humidity. “Wear it, forget it,” he says. So soft on the skin that you wouldn't remember you are wearing it.
Ancient Ayurvedic treatise Charaka Samhita hails the antimicrobial element of copper. It was used for ear piercing, preferred over gold because it can heal skin sepsis. The ancient tome recommends consuming water stored overnight in a copper bottle to enhance our antimicrobial abilities. The Edwin Smith Papyrus, an Egyptian book that’s considered a health authority, mentions ancient Egyptians treating wounds with copper water. The Hippocratic Collection also advises physicians to use it as a wound dressing for leg ulcers. De Medicina, a first-century medical treatise by Aulus Cornelius Celsus, a Roman encyclopaedia used to treat venereal disease. Copper was used in treating dysentery in World War II soldiers. During Covid-19, even allopathic doctors went about town recommending we drink water stored in copper bottles overnight to boost our immunity.
Copper releases copper ions to kill microbes or electrically charged particles. When these ions contact microbes, they puncture the cell membrane and damage the DNA and RNA. The metal’s assault on microbial DNA makes it useful for preventing antibiotic-resistant superbugs, like MRSA, from posthumously passing their genes to other microbes.
Not only does copper work in the lab, but it also works in the clinic. In a 2015 study, researchers found that adding copper to bed rails, call buttons, chair arms, tray tables, computers and IV poles
inpatient rooms reduced infections by 58 per cent.
Dr Rini Thomas, a consultant dermatologist with CureWell Hospitals in Chennai, says she is not surprised at the potential of copper. “Wounded soldiers in the Mughal era used to place copper filings on their wounds to reduce infection. I remember reading an article in 2017 about copper being used as a film on hand railings and safety gates in an amusement park in Chile. Five years later, nanomeshes most definitely look like something we could cover ourselves with, instead of draping the surfaces. The former would be a lot more effective as it retains touch directly with the humans,” she surmises.
Researcher Jae also writes about Korea using copper films covering touch screens, elevator buttons and hand railings in public places. The nanomesh, which one can stick onto touch screens and displays without sacrificing image quality, could therefore have vast potential in the Covid-ravaged world. The nanomesh was tested in its current form on a finger. The team hopes to do more work before they claim other advantages of copper in its new avatar.
Dr Mallika N, consultant microbiologist, Kamineni Hospitals LB Nagar, Hyderabad, describes copper as a ‘superstar’ among the elements. “Copper annihilates the respiratory chain of E.coli cells and is associated with impaired cellular metabolism. Polio virus is inactivated within 10 minutes of exposure to copper with ascorbic acid. Thus copper has the power to control a wide range of molds, fungi, viruses and harmful microbes. In India, we haven’t cashed on its properties in a big way, but nanomesh technology sounds like a game-changer to me,”she says hopefully.
How Jae created the mesh
The mesh is formed by spinning copper into random orientations and flattening it. The fibrous structure gives the mesh a high surface area to release copper ions. He compares it to a cotton candy machine.