Biologic Sensor Captures Infections on Hospital Catheters

The device aims to prevent painful urinary infections in elderly hospital patients.

The genetically engineered sensing device is suspended in liquid that can be painted onto the end of a catheter outside the patient's body. This liquid contains a protein that attaches to a small molecule called acyl-homoserine lactone (AHL), which is secreted by bacteria and found in urinary catheter infections. When AHL is present and intercepted by these molecular devices, a second protein is activated, which glows green. This causes the liquid on the catheter to change color, fluorescing a green color, indicating the presence of an early-stage infection.

The device was developed by biochemistry and bioengineering students and their supervisors at Imperial College London (UK). Prof. Richard Kitney of Imperial's department of bioengineering, one of the project's supervisors, explained the significance of the invention, saying, "Normally, in hospitals, doctors and nurses only find out that patients have a urinary infection from their catheter when the patients' temperature rises and they become ill. By the time these symptoms are displayed, the infection has traveled up the catheter into the body, which is very serious if left untreated. Our device would mean that healthcare workers would get a clear early warning sign--in the form of a fluorescing green signal--that an infection was present on the catheter. This would allow them to perform basic disinfection, removing the bacteria from the catheter, before it could take hold in the patient.”

Prof. Paul Freemont from Imperial's department of life sciences, who is also supervising the iGEM team, explained why getting undergraduate students involved in projects like this is so important, "Synthetic biology is a brand new type of science where we manipulate DNA to create biological devices based on engineering principles. It's an exciting field with countless possible applications, and MIT's iGEM competition ensures that some of the world's brightest young students get hands-on experience devising some of these applications themselves.

The device received a gold medal at the 2007 International Genetically Engineered Machines (iGEM) competition, held at Massachusetts Institute of Technology (MIT; Cambridge, MA, USA) on November 3-4, 2007.


Related Links:
Imperial College London
Massachusetts Institute of Technology