Colour-changing bandages can release antibiotics and prevent resistant microbes

Researchers have created a colour-changing and antibiotic-releasing bandage which indicates the presence of drug-resistant and drug-sensitive bacteria in wounds, so react accordingly to treat injuries. The researchers hope this could help both patient recovery and curtail the spread antibiotic-resistant microbes.

The study, published in ACS Central Science, shows how scientists developed a bandage that changes colour from green to yellow in response to the acidic environment of a bacterial infection. The material of the dressing reacts to this environment be releasing an antibiotic to destroy drug-sensitive bacteria.

A bandage changed colour from green to yellow, and from green to red, in the presence of increasing concentrations of drug-sensitive (DS) and drug-resistant (DR) E.coli, respectively (Credit: Adapted from ACS Central Science 2020, DOI: 10.1021/acscentsci.9b01104).

However, in the presence of drug-resistant bacteria, the bandage is changed to red by an enzyme produced by the microbes. Researchers shone a light on the bandage in response to this change, causing the dressing to release reactive oxygen species to kill or weaken the bacteria. According to the scientists, this made the bacteria more susceptible to the antibiotic which was also released from the bandage.

The team showed that the bandage could speed the healing of wounds in mice that were infected with drug-sensitive or drug-resistant bacteria and hope this could help what the World Health Organization (WHO) categorised as one of the biggest threats to global health.