Engineers at Leeds University have developed a diagnostic device that is much smaller than current models and can work with smaller samples, but is just as accurate.
Diagnostic devices work by identifying certain proteins in blood or urine that are associated with certain diseases. The Leeds device is more than ten times smaller than existing models, and the researchers believe the technology could allow them to reduce the size further still, allowing it to be used with even smaller samples – especially important with newborn babies, for example.
The researchers used an array of electrodes as the base of their device rather than a conventional glass slide. The individual electrodes are created using the same technology used to produce microchips, allowing them to be spaced 10 micrometers or less apart.
Conventional techniques use antibodies as receptors, but these can prove unstable. The new device uses an artificial robust antibody called a ‘peptide aptamer’ that can be attached to the electrodes and still bind to a specific target protein.
The Leeds researchers then devised a technique to attach different peptide aptamers to individual electrodes with very high precision. The electrodes are individually wired, so when the proteins of interest from samples (such as blood) bind to their associated peptide aptamer, an electronic signal is generated.
Because the basic technology of the new device is similar to that used widely within the computer industry, the researchers believe that the number of sensors in their system could be scaled up for use commercially, with the device itself taken down to nanoscale size for use with very small samples.