Development of a Plate-Based Optical Biosensor Fragment Screening Methodology to Identify Phosphodiesterase 10A Inhibitors

We describe the development of a novel fragment screening methodology employing a plate-based optical biosensor system that can operate in a 384-well format. The method is based on the "inhibition in solution assay" (ISA) approach using an immobilized target definition compound (TDC) that has been specifically designed for this purpose by making use of available structural information. We demonstrate that this method is robust and is sufficiently sensitive to detect fragment hits as weak as KD 500 mu M when confirmed in a conventional surface plasmon resonance approach. The application of the plate-based screen, the identification of fragment inhibitors of PDE10A, and their structural characterization are all discussed in a forthcoming paper.