Proteome Analysis Technology

Proteome analysis and DiaPat test - The technique

How does the DiaPat test actually work? We work with a capillary electrophoresis and a mass spectrometer. The urine sample is injected in a 90-centimetre glass capillary. An electrical voltage of 25,000 volts is applied there. In the voltage field, the proteins begin to migrate because they have a specific charge as molecules. The smaller they are, the faster they migrate because they have less resistance to the capillary. At the end of the capillary, where smallest droplets come out, another 3000 volts are applied. In this voltage the liquid literally explodes and we have the pure protein molecules. These are sucked into the mass spectrometer. Under voltage we can determine the masses of the proteins. This works by means of acceleration, so that the flight time of the particles in a high vacuum is measured. At the end of the mass spectrometer is a molecule detector, where the impacts of molecules are counted.

So far everything is physics. Then the statistics begin.

There are about 2000 proteins and peptides in urine. In tens of thousands of measurements during our years of research we have found different amounts of certain molecules in diseased and healthy people. Therefore, at the end of the test we have exact calculations according to certain statistics.

The trick here is a model of several significant molecules that assign the position in the test person according to certain parameters. The computer then calculates a diagnostic pattern out of these molecules. The detected proteins are compared in a database with defined marker lists that are typical for individual diseases. In this way, we researchers measure all 2000 proteins in the urine and then specifically query the corresponding proteins of the respective diseases. For example, for impending cardiac insufficiency these are 195 proteins, for a possible bladder carcinoma 85, and for chronic kidney diseases 273 proteins.