New Antibacterial Clothing: Secret Ingredient Revealed

One consequence of the media hunger for page views is a blurring of the line between news reporting and other forms of content.
This un-bylined story that has appeared under the BBC News banner since Wednesday probably looks to many readers, as it initially did to me, like a BBC News report:
A new anti-microbial treatment that can make clothing – including smelly socks – permanently germ-free has been developed by US scientists.
The spray-on solution can be applied to existing garments, according to the team from the University of Georgia. It is designed to offer low cost protection for healthcare facilities, such as hospitals.
via BBC News – New solution can help 'permanently get rid of germs'.
But it's just a rewrite of a University of Georgia press release penned by a UG public affairs specialist, Terry Marie Hastings:
A University of Georgia researcher has invented a new technology that can inexpensively render medical linens and clothing, face masks, paper towels—and yes, even diapers, intimate apparel and athletic wear, including smelly socks—permanently germ-free.
There's nothing inherently wrong with writing stories from press releases. Reporters do it all the time. But it's a rare press release that doesn't need verification or supplementation, and there's a major hole in the BBC story—and in the UG press release—that a reporter would have filled:
What is the new treatment?
When it comes to the question words, what is fairly important. The answer is not in the press release, but in the study that prompted it, in the American Chemical Society's Journal of Applied Materials and Interfaces.
There, the scientists themselves report that the anti-microbial agent has been known and used for years—a cationic polymer, like quaternary polyetheleneimine, which kills bacteria by tinkering with the molecular integrity of cell membranes.
The method used to attach the polyethylenimines to materials is also well known—the bonding agent benzophenone has already been used to attach the anti-microbial agent to glass, polymer, paper, and metal.
The achievement of the University of Georgia scientist, Jason Locklin, and his team, was figuring out how to attach ultra-thin layers of this combination of chemicals to textiles (and just about any other material).
Locklin and his colleagues sprayed the substance onto materials and exposed them to ultraviolet light, which causes a covalent bond with the host material.
Importantly, the anti-microbial surface remained even when the host material was washed or otherwise agitated. While the scientists want to kill bacteria on clothing and medical masks, they don't want their antimicrobial agent to discharge easily into the environment, where bacteria play an essential role in the chain of life.
They tested their treated materials with Staphylococcus aureus and Escherichia coli, the gram-positive and gram-negative bacteria that are always giving humans a bad day. They reported:
When the thickness of the polymer layer was greater than 50 nm, essentially almost all the bacteria were killed. This one step photochemical attachment process of an ultrathin antimicrobial coating is both simple and scalable for industrial applications.
In addition to Locklin, the scientists included Vikram P Dhende, Satyabrata Samanta, David M Jones, and Ian R. Hardin of the Department of Chemistry and Faculty of Engineering, University of Georgia in Athens, Georgia.