Silver bullet targets antibiotics to deep infections

A tiny metal and ceramic "bullet" could get antibiotics deep inside the body to target hard-to-treat infections with lower levels of antibiotics. The particle, developed at the Louisiana State University Agricultural Center's Department of Biological and Agricultural Engineering, has an iron core wrapped in ceramic and silver and then coated with molecules that target the bacteria, and inert forms of drugs (prodrugs) that are activated at the site of infection.

Because the delivery system has an iron core, doctors can use MRI to locate the nanoparticles once they have traveled through the tissues and arrived at the infected area. The prodrugs are activated at the infection site, either laser-guided by the imaging or by the bacterial infection itself.

The initial studies have used a steroid-based molecule that targets MRSA (methicillin-resistant Staphylococcus aureus), but different targeting molecules could be used for different types of infection.

"We use targeting molecules that have been identified to be attracted to particular bacteria," says Dan Hayes of LSU's AgCenter. "It's a particle delivery system--when it hits the right bacteria, it sticks."

Some deep-seated infections are hard to treat, especially those in areas with low blood flow, or associated with implants or joint replacements. By reducing the amounts of antibiotics needed to treat these deep-tissue infections, targeted delivery systems could cut the risk of antibiotic resistance, as well as reduce the need for repeat surgery and improve outcomes and quality of life for patients who are already vulnerable.

- read the press release