Bird flu. Salmonella. Staph infections. You can't turn on the TV or open a newspaper without seeing evidence of concern over infection and illness. The germ battle rages in pharmaceuticals and wound care. In fact, there's a surge in the wound care market that experts attribute to an aging and sicker patient population that's more prone to skin breakdown and infection. Nanotechnology is playing a high-profile role here as an enhancement to bandages, dressings and other health care products. Their key ingredient is silver nanoparticles or nanocrystals which kill bacteria, viruses and germs. We'll talk about the science of how they work in a minute, but first let's look more at the growing demand.
Consider this: there are more germs on the average office desktop than in a toilet. Ten million germs are located on the desktop, phone handset, mouse and keyboard. Scary, yes? That's why concerns over germs have also made the move into mainstream consumer products like silver-infused adhesive bandages, not to mention hand sanitizers and a myriad of disinfectant sprays and wipes.
It's no wonder that manufacturers of all kinds are using nanotechnology to add germ-fighting capability to their products. You may have seen some of them. Several appliance manufacturers have added nanotech-enabled antibacterial coatings to refrigerator walls, shelves and icemakers. Surface treatments are included in the metal of HVAC systems to kill microbes growing in those moist environments. You can now buy pillows, cutting boards, food storage containers and clothing that combat "bugs."
How do silver nanoparticles fight germs? Silver has long been known to be a safe, naturally anti-bacterial and anti-viral. In fact, Ancient Egyptians and Phoenicians used silver particles to control germs in the food and water supply. (Fun fact: the water tanks in spacecraft have long been coated with silver.)
Today, there are several mechanisms for utilizing silver as an anti-bacterial. One method breaks down silver into nanoparticles that are much smaller than naturally occurring particles. This creates greater solubility and an improved ability for the silver atoms to migrate through a germ's cell walls to disrupt functioning, killing the organism. This nanoscale material is added to fibers, plastics and coatings. Another method coats surfaces with embedded nano-silver "mounds" which kills germs and also helps prevent them from settling on the surfaces where they grow.
This antibacterial property is a much-appreciated product enhancement you could be adding right now. Think big! Since most germs are passed by hand-to-hand contact, wouldn't it be smart to have a coating like this on the company's copier? What about cell phones and other electronics? Doorknobs? Car dashboards? Childrens' toys and car seats? You get the idea.
Of course, in the end, nano-silver may not turn out to be the gold standard of germ control. In health care, there's always a "next." What are the issues? For one, in most cases - and especially for surface treatments - the regular use of traditional germicidals is recommended. The silver surface treatment alone can be overwhelmed by bacterial growth. There is also some question of the durability of some applications. Will the nano-crystals wash out of fabric? Abrade off surfaces? Can it be reapplied?
There are also some cost issues. Silver isn't inexpensive, and the price trends aren't downward.
In addition, there are some indications that certain microbes may be becoming resistant to the silver. Lab research confirms it, as does a colony of silver-resistant bacteria that lives in a river near Rochester, New York.
The fact is, a germ's ability to mutate and become resistant to any treatment is a constant concern in health care. And it's worth worrying about. Example? In 1941, when penicillin was the new wonder drug, 40,000 units a day would cure pneumonia in four days. Today, a dose of 24 million units a day might not be enough.
So while we capitalize on the awesome possibilities of nanoscale silver, the hunt is on to replace this first-generation technology with an advanced-generation solution. It could be new types of nanomaterials that kill germs more effectively. There's also the development of surface structures that prevent germs from adhering, creating a "self-cleaning" shell on a table or scalpel. I've even seen some early-stage research that approaches the problem in surprising new ways. And you'll be seeing them all in the not-to-distant future.
Next time you get a skinned knee, reach for an apple from the fridge, or touch your desktop, let it remind you that the germ-fighting revolution has begun. It's time to use nanotechnology-based solutions to attack the enemy.
Scott E. Rickert is chief executive of Nanofilm, Ltd., located in Valley View, Ohio. His e-mail address is [email protected].