There’s a new weapon in the battle against bacteria and viruses—a polymer that kills pathogens on contact. The material could be used for biomedical applications, smart textiles, and food packaging. A team led by North Carolina State University’s Richard J. Spontak and Reza A. Ghiladi studied the pathogen-fighting abilities of the material—a commercially available copolymer in which two hydrophobic regions (shown in blue) bookend a hydrophilic region loaded with sulfonic acid groups (shown in red). The sulfonic acid groups decrease the pH at the polymer surface, and microbes coming in contact with the material experience a sudden drop in pH. This kills the microbes within just five minutes by destroying their membranes, damaging their enzymes, and denaturing their proteins. In tests, the polymer was effective against six types of bacteria, including a “superbug,” methicillin-resistant Staphylococcus aureus, which is a dangerous bacterium found on surfaces and equipment in hospitals and other medical facilities. The material also eradicated vesicular stomatitis virus, human adenovirus-5, and influenza A virus (Mater. Horiz. 2019, DOI: 10.1039/c9mh00726a). Although the polymer loses its potency over time, it can be revived by simply spraying it with an acidic solution like vinegar.