Bacterial infections are linked to around 8 million deaths per year worldwide, and this number is expected to rise, especially due to antimicrobial resistance. A major problem in treatment is that current diagnostic methods are slow. Standard clinical tests take 1–3 days, and even faster DNA-based methods such as PCR still require many hours.
In this project, Richards and colleagues will develop a virus-based biosensor for rapid detection of bacterial molecules linked to infections and sepsis. They use bacteriophages (viruses that specifically infect bacteria) together with a highly sensitive optical technique called interferometric scattering (iSCAT) microscopy, which can “weigh” tiny particles with light without the need for fluorescent labels. This allows for the detection of very small amounts of bacterial material quickly and specifically. The resulting platform will be an important step towards drastically reducing the time from suspected infection to effective treatment. In the longer term, the project aims to turn it into a cheap, user‑friendly sensor that can be used directly at the point-of-care.