Assay technologies

Modern assay technologies in drug design make feasible the screening of upward of 1 million compounds. The throughput of such assays enables the rapid identi-... 

The first step in the process involves the development of a suitable HTS assay format. A more detailed discussion of the formats available for HTS by target class are outlined later in this chapter. This section will focus on some of the practical considerations to determine the proper assay technology for an HTS campaign. 

The truth most likely lies somewhere in between. Bender [67] published the most quantitative study to date on the success of HTS at Novartis. Several conclusions could be drawn. Particular target types and assay technologies have a great impact on screening success, and this was not always correlated to the number of identifying hits in the HTS runs. For assay formats used a minimum of five times, LC/MS readouts succeed 83% of the time, followed by FP assays, which succeed in 72% of the cases. TR-FRET showed a success rate of 70%, with FLIPR assays (61%), fluorescence intensity readouts (59%), and AlphaScreen (60%) performing... 

If SPA has shortcomings, and every assay technology does, they include its requirement for pipetting beads, which can be challenging for liquid handlers, and its use of radioisotopes. 

Sills, M.A., Weiss, D., Pham, Q., Schweitzer, R., Wu, X., and Wu, J.J., Comparison of assay technologies for a tyrosine kinase assay generates different results in high throughput screening, /. Biomol. Screen., 7,191, 2002. 

Comley, J., Continued miniaturisation of assay technologies drives market for nanolitre dispensing, Drug Discov. Today, 5, 43, 2004. 

Sittampalam SS, Kahl SD, Janzen WP. High-throughput screening advances in assay technologies, Current Opinion in Chemical Biology 1 384-391 (1997). 

Advanced assay technology Structure-based design Ligand-based design QSAR... 

P. J., Kelly, M. A., Schriemer, D. C. Frontal affinity chromatography-mass spectrometry assay technology for multiple stages of drug discovery applications of a chromatographic... 

Silvennan L, Campbell R, Broach JR. (1998) New assay technologies for high-throughput screening. Curr Opin Chem Biol 2 397 03. 

A complementary approach is to conduct the assays under high-throughput automated conditions. This can be either through the miniaturization of assays, that is, 96-384 plates and if possible 1536, or through the use of alternative assay technologies (e.g., microfluidics). Both scenarios require studies of equivalency testing and backwards compatibility with previous methods and results. 

Nondinical assessment of cardiac safety must be performed for a compound to qualify to be submitted to the health authorities to begin studies in man. For this purpose the regulatory bodies require that the cardiosafety assays should follow the principles of GLP wherever possible. The following assays/technologies are frequently used to predict potential clinical QT liability. 

The workload is increasing in both volume and scope in all branches of laboratory medicine. In mainstream clinical chemistry, the past 25 years have seen astonishing developments in assay technology and instrumentation assays that were performed manually with a few dozen assays a day can now be accomplished automatically by the thousands. In biochemical genetics (molecular genetics aside), automation has had a less dramatic impact. 

G Zhao, TI Meier, WK Yeh. Penicillin-binding proteins as antimicrobial targets expression, purification, and assay technologies. In HA Kirst, WK Yeh, MJZmijew-ski, Jr., eds. Enzyme Technologies for Pharmaceutical and Biotechnological Applications. New York Marcel Dekker, 2001, pp. 263-287. 

Penicillin-Binding Proteins as Antimicrobial Targets Expression, Purification, and Assay Technologies... 

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