‘Pregnancy test’ disease analyser developed
Chemists at Johannes Gutenberg University Mainz (JGU), Germany, have developed a quick, cost effective method of detecting the presence of viruses. The new method for ‘parallel protein analysis’ is capable of identifying hundreds of different proteins in tiny samples.
Commenting on their discovery, part funded by the European Research Council, Professor Carsten Sönnichsen said: “We see possible applications of this technique in medicine, where it could be used, for example, for the rapid diagnosis of a wide range of diseases. It would be almost as easy to use as a pregnancy test strip.”
The test involves placing a tiny drop of blood, saliva, or other bodily fluid on a small test strip, which is then placed in a device developed at the JGU Institute of Physical Chemistry. This device is able to identify the specific proteins in the fluid and thus allows to quickly and reliably differentiate between harmless micro-organisms and dangerous pathogens.
In order to detect the many different substances present in a small sample, the sensors are required to be as tiny as possible, preferably the size of nanoparticles. The team of scientists have designed a sensor the size of a pin capable of performing a hundred different individual tests on a surface that is only of one-tenth of a square millimetre in area. The ‘test strips’ consist of glass capillary tubes that have gold nanoparticles as sensor elements on their internal surfaces.
When a protein docks with a short DNA strands, called aptamers, the corresponding nanoparticle changes its colour. The colour changes can be detected with the aid of a spectrometer. For this purpose, the capillary tubes are placed under a microscope designed, constructed, and provided with the necessary software by the Mainz-based team of chemists.
The article is published in journal Nano Letters.
