2012-03-08

Co.Exist

No More MRSA: Nanomedicine Will Destroy Antibiotic-Resistant Bacteria

Antibiotics might be one of the miracles of modern medicine, but they’re not actually so great. Now, instead of damaging cells, we’re just going to blow them up.

Humans have made the regrettable mistake of overusing both antibiotics and antimicrobial consumer products. Now we have antibiotic-resistant bacteria--like MRSA--popping up in our hospitals, and toxic antibacterial ingredients like triclosan seeping into our water supply. But MRSA may not be long for this world, and antimicrobials may soon be left out of our toothpaste and mouthwash.

Last spring, IBM and the Institute of Bioengineering and Nanotechnology discovered a new kind of polymer that can seek out and destroy antibiotic-resistant bacteria and diseases. I recently visited Jim Hedrick at IBM Research to learn more.

The biodegradable polymers--which are made out of nanomaterials--have a magnet-like attraction to infected cells. Once these cells are reached, the polymer goes inside, destabilizes them, and causes them to explode.

It’s a process that’s similar to what the body already does to fight infection. When we’re sick, antimicrobial peptides destabilize infected cell membranes and force the contents to leak out. "We’re working in the same way nature does. We’re not going in like antibiotics and trying to do a chemistry function. We’re just going in and destabilizing," explains Hedrick.

While traditional antibiotics develop resistance because the chemical reactions they trigger leave cell walls and membranes undamaged, IBM’s polymers completely destroy them, leaving bacteria defenseless. The polymers are also targeted enough that they leave surrounding healthy red blood cells unharmed, unlike antibiotics, which can do a number on your body.

The polymers aren’t restricted in use just to MRSA. "We’re able to go after some pretty broad spectrum targets, one of which is fungi. We now have data on E. Coli. We’ve been able to eradicate E. Coli quite efficiently," says Hedrick. "Even some of the microbes that have more robust cell walls, we’re starting to be able to knock down."

IBM and its colleagues have already shown that the polymers are non-toxic to animals (the Institute of Bioengineering and Nanotechnology does animal testing). The next step: thinking commercially. Theoretically, for instance, the researchers could create a non-toxic deodorant that only targets microbes which cause bad odor.

Hedrick’s research also extends into the use of nanomedicine to deliver therapeutics, like chemotherapy for cancer. A nanoparticle used to deliver drugs would have to be stealth (so it doesn’t get cleaned out by the body) and effectively send its contents directly to the tumor. "The idea is to have a nanoparticle small enough to circulate and get sucked down into the tumor," says Hedrick. A chemotherapeutic delivered by nanoparticles immediately kills tumor cells--without harming healthy surrounding cells (and in turn, without making humans unnecessarily sick).

Chances are, we’ll see nanoparticle deodorant long before we see MRSA and cancer applications. There are, of course, less stringent federal regulations for products like mouthwash, deodorant, and toothpaste than for disease-targeting polymers.

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2 Comments

  • nosybear

    Okay - system thinking in action.  We're already seeing the results of our microbial phobia in decreased microbe counts in streams from the nano-silver particles that get washed out of our antimicrobial socks.  So we start using this stuff and releasing it into the environment, what will that do to microbial populations in streams and lakes, the bases of the food chains for fish?  Before we start making antimicrobial deodorants out of nanomaterials which, even if they are biodegradable will last long enough to get into rivers and streams - exponential decay, you know - perhaps we should see what it does to that part of the world apart from human armpits and feet.