BiMedis has already featured a very interesting article about the clinical trials of the handheld autofluorescence imaging platform, PRODIGI. In recent times, several freshness indicators have been patented for food products which react to time and temperature, letting you know when something spoils. Now, researchers have developed a wound dressing that glows green when it detects the presence of pathogenic bacteria in the wound. Just like the PRODIGI, this smart dressing offers early detection of harmful bacteria and will have a profound effect on the prevention of complications and may reduce the use of antibiotics.

A dressing unlike any other

 As the famous writer, philosopher and politician, Benjamin Franklin (the guy on the $100 bill) once said, “An ounce of prevention is worth a pound of cure.” A team of British scientists took it upon themselves to develop a smart wound dressing that changes color when it comes into contact with certain bacteria. In a wound, bacteria from the surrounding skin and other sources quickly find their way in and start to multiply forming colonies. This is absolutely normal, but there are some cases where the bacterial load reaches a critical point, at which immune clearance is no longer effective. It’s at this point that medical intervention becomes a must, so Ben Franklin hit the nail right on the head.

The prototype of the ‘smart’ wound dressing: not infected (left), Infected with Staphylococcus aureus or Pseudomonas aeruginosa (right) © University of Bath

The scientists tested their prototype dressing using a pig skin model of burn wound infection, as it is very similar to human skin, and found that it was very effective for detecting infections caused by bacteria that encase themselves in a biofilm. Like any living thing, bacteria also have their own interests to uphold, and they protect them fiercely by enclosing themselves in a protective “bubble”, or the more technical term, an extracellular polymeric matrix.    

Prevention is key

Toby Jenkins, a Biophysical Chemist in charge of the project explains that, “Our medical dressing works by releasing fluorescent dye from nanocapsules triggered by the toxins secreted by disease-causing bacteria within the wound. The nanocapsules mimic skin cells in that they only break open when toxic bacteria are present; they aren’t affected by the harmless bacteria that normally live on healthy skin. Using this dressing will allow clinicians to quickly identify infections without removing it, meaning that patients can be diagnosed and treated faster. It could really help to save lives.”

The current method for identifying wound infections takes up to 48 hours, losing precious time and increasing the chance of complications. Also, as a result of this time-consuming task, patients are often prescribed antibiotics as a precaution. This of course adds to the growing problem of antibiotic resistant bacterial strains, not to mention the possible side-effects, such as diarrhea, abdominal pain, nausea/vomiting and rashes.

Looking to the future

This “smart” dressing could be a real breakthrough in wound care because it’s simple, effective and you see the results before your eyes. With this innovation, doctors can monitor the healing process at the patient’s bedside, without waiting for lab tests. BiMedis gives it two thumbs up!

Thet, N., Alves, D., Bean, J., Booth, S., Nzakizwanayo, J., Young, A., . . . Jenkins, A. (2015). Prototype Development of the Intelligent Hydrogel Wound Dressing and Its Efficacy in the Detection of Model Pathogenic Wound Biofilms. ACS Applied Materials & Interfaces. doi:10.1021/acsami.5b07372

By Dr. Yuriy Sarkisov, BiMedis staff writer