A solar-powered nano filter capable of filtering antibiotics and dangerous carcinogens from large bodies of water has been developed by researchers at the University of Cincinnati. The new technology is significantly more effective than the currently used filtering technologies composed of activated carbon.
The filter is composed of two bacterial proteins that are able to absorb roughly 64% of the antibiotics present in surface waters, versus the 40% that is absorbed by current technology. Many of the world’s waterways are now heavily polluted with antibiotics, pharmaceuticals, and other forms of pollution. Effective means of addressing this problem would certainly be welcome.
As an aside, the technology also possesses the interesting capability of reusing the antibiotics that have been trapped.
When significant levels of antibiotics are present in surface waters (as they now are throughout much of the world), they kill many microorganisms that are important to the health of the local ecosystem. And they also lead to the emergence of new strains and increased numbers of antibiotic resistant bacteria.
So, as a result, “the newly developed nano filters, each much smaller in diameter than a human hair, could potentially have a big impact on both human health and on the health of the aquatic environment (since the presence of antibiotics in surface waters can also affect the endocrine systems of fish, birds and other wildlife),” a University of Cincinnati press release states.
Interestingly, the new filter actually makes use of “one of the very elements that enable drug-resistant bacteria to be so harmful, a protein pump called AcrB.” David Wendell, an assistant professor of environmental engineering at the University of Cincinnati, stated: “These pumps are an amazing product of evolution. They are essentially selective garbage disposals for the bacteria. Our innovation was turning the disposal system around. So, instead of pumping out, we pump the compounds into the proteovesicles.”
In order to power the pumping mechanism, the researchers made use of “a light-driven bacterial protein called Delta-rhodopsin which supplies AcrB with the pumping power to move the antibiotics.”
All that needs to be present for the technology to work is sunlight.
Wendell continued: “So far, our innovation promises to be an environmentally friendly means for extracting antibiotics from the surface waters that we all rely on. It also has potential to provide for cost-effective antibiotic recovery and reuse. Next, we want to test our system for selectively filtering out hormones and heavy metals from surface waters.”
Heavy metal pollution is a significant and growing problem in many parts of the world. A simple and economical means of filtering these materials from the world’s waterways would have significant utility in many poorer regions of the world. Common DIY water filtering and purification technologies/techniques (such as SODIS) typically don’t help much with regards to heavy metal pollution.
The new research was recently published in the journal Nano Letters.