Experts Want To Weaponize Oxygen To Attack Bacteria

Scientists show how light-activated oxygen can be a powerful killer in a method that may lead to ground-breaking treatment options.

Antibiotic-resistant bacteria are a pain to many patients as well as medical professionals.

MRSA, which is a methicillin-resistant staph infection, can be life-threatening and is notoriously fast to spread. CNN says that many MRSA infections take place in hospital or other health care settings, since individuals with weaker immune systems are prone to it.

A New Weapon Against Antibiotic-Resistant Infections

To address these types of diseases, a group of researchers devised a new antibiotic-free technique that has the potential to treat various microbial infections and even cancer.

"Instead of resorting to antibiotics, which no longer work against some bacteria like MRSA, we use photosensitizers, mostly dye molecules, that become excited when illuminated with light," Peng Zhang, Ph.D., explains in a statement. "Then, the photosensitizers convert oxygen into reactive oxygen species that attack the bacteria."

When the photosensitizers react to the light, they turn the oxygen into weapons that can destroy the infection-causing bacteria.

The team presented their findings at the 256th National Meeting & Exposition of the American Chemical Society.

Zhang says that the photosensitizers can be introduced to the market as a spray or gel product. Medical professionals can simply spray or apply it on any surface, then expose it to blue or red light to eliminate the bacteria present.

It also reportedly shows potential in direct wound applications for eradicating infection and helping it heal. Experiments conducted on human skin samples have shown that the photosensitizers don't kill skin cells.

Even more impressively, Zhang says the nanoparticles are ideal for killing skin cancer cells due to its effectivity with red light, which penetrates deep in the skin.

How The Researchers Succeeded

It's not the first time that the method has been explored, but previous attempts weren't able to kill enough microorganisms to make a significant impact on the infection.

Previous researchers found it difficult to do damage, since photosensitizer molecules are difficult to corral. Photosensitizers also tend to be hydrophobic, which is problematic since microorganisms typically thrive in aquatic environments.

For a more effective attempt, Zhang and the rest of the team designed a water-dispersible hybrid photosensitizer that has noble metal nanoparticles with amphiphilic polymers to entrap the molecular photosensitizers.

The authors say that the metal particles provide a plasmonic enhancement effect, which produces a more reactive oxygen species. Their new version also concentrated the photosensitizers in one spot, so the hit is more localized on the bacterial cells.