Attività

Drug resistance – the problem

Drug resistance is among the greatest threats to worldwide health. If bacterial infections could be sensed early enough

to treat them before they take a hold on the patient, it would help avoid serious infections. And if the bacteria resist the

antibiotic, being able to detect this would be crucial in switching drugs to arrest the infection before it spreads.

At present, the methods of detecting antibiotic resistance are expensive, require professional expertise, and take too

much time. Moreover, using antibiotics for infections that are resistant to them promotes even more drug resistance.

Colorimetric methods to the rescue

The new study describes a way of doing just this, based on a color-changing material. Described as “a portable paper-

based band-aid (PBA)”, it is a colorimetric way of sensing and treating sensitive bacterial infections while signaling the

presence of drug-resistant bacteria as well.

Early detection of infection in this study exploits the microenvironment of bacterial growth, which includes an acidic

pH, various toxins and enzymes. Acidity is an easy way to track the presence of pathogenic bacteria because it is due to

their breakdown of glucose. Drug resistance, on the other hand, depends on the presence of the beta-lactamase and similar

enzymes. The presence of beta-lactamase is a widely used indicator of bacterial antibiotic resistance because it denotes

resistance to the extremely common beta-lactam antibiotics.

Once drug resistance has been identified, photodynamic therapy and other similar treatments have been adopted to increase

the level of reactive oxygen species (ROS). These molecules act on multiple cell targets associated with drug resistance,

including the bacterial cell wall, nucleic acids, and proteins. A careful use of this strategy is necessary since ROS attack

healthy cells and bacteria indiscriminately.

The innovation

The need of the hour is a portable, cheap and accurate device to detect and overcome antibiotic resistance. Paper-based

platforms, including biosensors and sterilization paper, have stolen the limelight in this regard because of multiple

advantages: low cost, sustainability, safety, and ease of adjustment. The current study focuses on a paper-based bandage device to detect and treat infection selectively

after sensing antibiotic resistance.