UCL: Laser-activated antimicrobial for treating infected wounds

Research lead

Researchers led by Michael Wilson at the Eastman Dental Institute in London, part of University College London, have shown that a dye, indocyanine green, generates antimicrobial compounds when activated by near infrared laser light.

Activated indocyanine green is capable of killing a wide range of bacteria including Staphylococcus aureus, Streptococcus pyogenes and Pseudomonas aeruginosa, and the dye is safe for humans.

A particular strength of this approach lies in the variety of ways in which the chemicals produced by the activated dye harm bacteria, meaning that they are unlikely to be able to develop resistance. “The mechanism of killing is non-specific, with reactive oxygen species causing damage to many bacterial components, so resistance is unlikely to develop – even from repeated use,” said Wilson.

The laser-activated treatment, described in a study published this week in BMC Microbiology, is expected to be useful in treating useful in treating infected wounds.

Although near-infrared light is known to be capable of producing heat, Wilson said, “Substantial killing of all of the bacteria tested was achieved without causing any temperature rise. The benefit of the laser described in this study is that it produces light that is more able to penetrate deep wounds, increasing the area cleansed.”