a technique that measures the mass-to-charge ratio (m/z) of ions in the gas phase has assumed a key role in most of the proteomic workflows. In particular, the surface-enhanced laser desorption ionization – time of flight (SELDI-TOF) technology represents a very novel and promising approach combining chromatography and mass spectrometry. The combined use of a proteinchip technology allows the selective capture of proteins of interest (autoantibodies) directly from the original source material and without sample preparation. This, in turn, makes this technique very simple and suitable for clinical applications. In addition, the throughput is very high, and the technique requires far less biological material than conventional methods.