IBM scientists developing nanoparticle to fight drug resistance

Scientists at IBM are developing a new type of nanoparticle that can kill drug-resistant bacteria by poking holes in them.

The IBM researchers hope that the new drug could be used to combat the emerging problem of antibiotic-resistant bacteria because microbes would be less likely to develop defenses against it, according to

Drug-resistant bacteria have become a major problem throughout the world. In 2005, according to the Centers for Disease Control and Prevention, 95,000 Americans developed a life-threatening staph infection that was resistant to multiple kinds of antibiotics.

Microbes can develop a resistance to traditional antibiotics within two decades, in part because they typically target a particular metabolic pathway in the cell. Drugs that target the entire cell membrane of a microbe are believed to be less likely, or at least to be slower, to evoke resistance.

"We're trying to generate polymers that interact with microbes in a very different way than traditional antibiotics," James Hedrick, a materials scientist at IBM's Almaden Lab in San Jose, California, said, according to

In order to develop a nanoparticle that would both attack the cell membrane of invading bacteria and dissolve harmlessly in the body, the IBM team used three types of polymer building blocks. The center of the polymer sequence is made of an element that is water soluble and tailored to react with bacterial membranes. At each end of the polymer backbone is a hydrophobic sequence.

When a small amount of these chains are added to water, the polymers self-assemble into spheres with shells made entirely of the part that interacts with bacterial membranes, reports.

In tests conducted in collaboration with the Singapore Institute of Bioengineering and Nanotechnology, the nanoparticles were found to be capable of bursting open and killing gram-positive bacteria similar to drug-resistant staph and some types of fungi.

Different bacteria would not be vulnerable to these nanoparticles, but IBM is working on other kinds as well.

"Through molecular tailoring we can do all sorts of things." Robert Allen, senior manager of materials chemistry at IBM Almaden, said, according to

More testing will be needed in order to determine whether the nanoparticles will be safe and effective in humans. Other drugs that have utilized membrane piercing have proven to be toxic to animal cells or not capable of working within the complex environment of the human body.

Initial tests of the IBM nanoparticles with human blood cells and in live mice has been promising. Regardless, Allen says IBM will most likely stay out of the pharmaceutical business, but the company plans to partner with a healthcare company to license the polymer drugs.