"We showed that 99% of the potentially dangerous Staphylococcus aureus bacteria in infected wounds can be killed using a green dye that gives off toxic molecules when it is activated by near-infrared light," said Dr Ghada Omar from University College London, UK.
Near-infrared light is commonly used in fibre-optics and telecommunications because it passes through glass easily. Researchers have now discovered that it can be used alongside a dye to kill bacteria that infect wounds and burns. The dye used, called indocyanine green, is harmless to humans and inactive in the dark. However, it gives off toxic molecules that rapidly kill the bacteria when it is triggered by the right light wavelengths.
"The chemicals produced when the dye is activated harm the bacteria in such a wide variety of ways that it is unlikely bacteria could ever develop resistance to the treatment," said Dr Omar. This makes it ideal - and possibly the only option - for treating infections with multiple drug resistant bacteria, including MRSA."
Infected wounds are a major problem for thousands of hospital patients every year, and up to 9% of hospital acquired infections occur during surgery, contributing to 77% of deaths from surgical operations. These infections increase the length of time patients must remain in hospital by an average of 10 days, increasing the cost to the NHS by up to two and a half times to as much as £2,400 per patient.
The new light-activated antimicrobial treatment is less effective when there are low oxygen levels in the infected tissues. This is a common problem in injuries where blood systems have been damaged, or where the injury is further away from the bodies' main vascular systems. The latest work from the University College London team shows that even with very low oxygen levels in the damaged tissues, most dangerous bacteria can still be killed using the light-activated dyes.
"Increasing oxygen levels in the infected tissues would maximise the killing effect", said Dr Omar. "But even with low oxygen levels a very wide range of bacteria were killed, including over 70% of Streptococcus pyogenes and Staphylococcus aureus, which has become one of the most drug resistant bacteria in hospitals." Dr Omar's co-authors on the study include Michael Wilson and Sean Nair of the Division of Microbial Diseases, UCL Eastman Dental Institute.
The research is part of a programme looking for a simple, rapid and cheap alternative treatment for infected wounds and ulcers that do not respond to conventional antibiotics.
Lucy Goodchild | alfa
Deep stimulation improves cognitive control by augmenting brain rhythms
04.04.2019 | Picower Institute at MIT
Black nanoparticles slow the growth of tumors
04.04.2019 | Technische Universität München
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.
Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...
The technology could revolutionize how information travels through data centers and artificial intelligence networks
Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...
Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.
Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...
Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna
A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
18.04.2019 | Life Sciences
18.04.2019 | Physics and Astronomy
18.04.2019 | Life Sciences