TECHNOLOGICAL ADVANCES IN HIGH-THROUGHPUT SCREENING

A variety of assay technologies continue to be developed for high-thro ughput screening. These include cell-based assays, surrogate systems u sing microbial cells such as yeast and bacterial two-hybrid and three- hybrid systems, and systems to measure nucleic acid-protein and recept or-ligand interactions. Modifications have been developed for cell-fre e, homogeneous assay systems, such as time-resolved fluorescence, fluo rescence polarization and the scintillation proximity assay. Innovatio ns in engineering and chemistry have led to delivery systems for nanol iter volumes and sensitive biosensors for ultrahigh-throughout screeni ng conducted in nanoliter and picoliter volumes. Spectroscopic methods have been extended to read single molecule fluorescence. Technologies are being developed to identify new targets from genomic information in order to design the next generation of screens.