In a new strategy against the potentially deadly infections that often develop around devices such as catheters, artificial heart valves, and replacement joints, scientists are devising materials that actively prevent bacteria from clinging. James D. Bryers, codirector of the Center for Biofilm Engineering at Montana State University in Bozeman, described his group's work on such materials at a recent meeting in San Francisco of the American Chemical Society.
Doctors commonly try to thwart infections with high doses of antibiotics.
The treatment works well against free-floating bacteria but is often useless against the thick films of bacteria on implants, Bryers says. Moreover, he has some evidence that the bacteria change genetically when they hit a surface, swapping genes for antibiotic resistance. The treated PEU releases a potent concentration of ciprofloxacin at its surface, killing bacteria that come in contact with it but not providing a high dose to the rest of the body. The problem is that dead cells pile up on the material. A better strategy, Bryers says, would be to prevent the bacteria from sticking to PEU in the first place.