Portable biosensor

Researchers from the University of Cambridge and the Medical Research Council (MRC) are part of a team which has just been awarded a grant of nearly £1million from the Biotechnology and Biological Sciences Research Council (BBSRC) to create a biosensor device which would be able to detect diseases in humans quickly and cheaply.

The device would be small and portable and would be able to detect cancer, as well as infectious viruses such as avian flu. Similar to a mobile phone, it could be used at a patient's bedside as well as in the field.

The Cambridge branch of the project is being led by Dr. Paul Ko Ferrigno from the MRC Cancer Cell Unit and Professor Piero Migliorato from the University of Cambridge’s Department of Engineering. Others include Dr. Jason Davis from the Oxford University Chemistry Department and Dr. Ejaz Huq from the Central Microstructure Facility at the Rutherford Appleton Laboratory.

The device would work on the principle that  “peptide aptamers”, special types of proteins that can be coupled to Thin Film Transistors (TFTs), can be used to detect the presence of other proteins in a sample taken from a patient.  Once the strands of DNA from the two types of protein interact with one one another, they create a unique electrical signal that can be detected and analysed.

In the proposed device, a user would place a sample on a small disposable card containing the TFTs. The card would then be inserted into the phone-like device, where the samples would be comibed with the peptide aptamers and the electrical signals analysed. The process would then show whether a sample does or does not have tell-tale proteins which would suggest the patient has a disease.

 “Such a device would solve not one but two different problems. The first is that it would enable population-wide screening, at home or in a doctor's surgery, to allow early diagnosis of diseases such as cancer- where the earlier we pick up symptoms, the more effectively we can treat the patient. The second is that biologists will finally have a tool that will allow them to answer literally hundreds of thousands of questions simultaneously- all for the price of a new test tube! This is an unusual marriage of biology and cutting edge engineering that should really pay dividends in our own lifetimes,” said Dr. Ko Ferrigno.

It is hoped that the device will be completed in the next two to five years.