Biomolecular screening is an essential part in the early phase of the drug discovery process.

Large numbers of organic molecules are being tested in well defined biological assay systems, with the purpose of identifying the few molecules which interact specifically with the protein target and could serve as starting points for chemical lead optimization.

Molecules which show a significant biological activity are further tested and validated in a panel of functional enzymatic or cellular assays.

The predominant assay readout systems are Ca flux and membrane potential measurement assays for receptor and ion channel targets and kinetic assays, based on time-resolved fluorescence, fluorescent energy transfer, luminescence or absorption readings.

Protein-protein interactions are central to many signaling pathways and are studied with conventional ELISA technology or with a novel detection system based on electrochemiluminescence.

Analysis of intracellular protein aggregation events, being the cause of many neurodegenerative diseases, is now possible using high content screening technology.