Protein analysis, identification and characterization directly from complex mixtures such as crude biological samples can be quicker and more accurate with the ProteinChip system. Researchers routinely can achieve results in less than one day. The system can analyze molecules with a molecular weight of less than a few hundred daltons to more than 250kDa, extending the mass range accessible by 2-D gel techniques, which is typically 10kDa to 150kDa. This is of particular interest in the lower mass range, where the detection of bioactive peptides and second messenger molecules by 2-D gel techniques has been problematic.
The system uses surface-enhanced laser desorption/ionization (SELDI) mass spectroscopy and ProteinChip arrays. Activated arrays capture proteins directly from biological samples. Adding one of many different molecules tailors the activity of the arrays; chemically activated arrays give overall protein expression profiles similar to 2-D gels, and biologically activated arrays produce Western-blot style results revealing interactions between proteins.
Interpretation of protein expression can be simplified through the systems software. Data can be viewed in a number of formats, making direct comparison to 2-D gels or Western blots possible. Differential expression patterns of proteins can be quickly generated from samples treated in different ways, highlighting proteins of potential interest. As a result, accelerated discovery and validation of biomarkers as indicators of disease phenotypes is possible using this system. Ciphergen Biosystems Ltd.