Assay, scintillation proximity

Gobel, J., Saussy, D. L., and Goetiz, A. S. (1999). Development of scintillation-proximity assays for alpha adrenoceptors. J. Pharmacol. Toxicol. Meth. 42 237. 

Radioactive assays have fallen out of favor over the last decade, and few HTS assays are run using radioactive tracers. Safety, cost, and the need to dispose of large amounts of waste, along with the availability of nonradioactive formats have hastened their decrease. However, scintillation proximity assays (SPA) are still run in some HTS laboratories. 

Udenfriend, S., Gerber, L., and Nelson, N., Scintillation proximity assay a sensitive and continuous isotopic method for monitoring ligand/receptor and anti gen/anti body interactions, Anal. Biochem., 161, 494, 1987. 

Delle Fratte, S., Piubelli, C., and Domenici, E. (2002). Development of a high-throughput scintillation proximity assay for the identification of C-domain translational initiation factor 2 inhibitors. J. Biomol. Screen. 7, 541—546. 

HTS screening is often based on miniaturized cell assays that enable chemical libraries to be screened for molecules that present different biological activities and sometimes-different biological targets using fluorescence, scintillation proximity assays (SPA) and luminescence as detection techniques. 

SPA (scintillation proximity assay) Amersham Biosciences (GE Healthcare) Binding of radiolabeled moiety to beads containing scintillant produces luminescent signal... 

Picardo, M. and Hughes, K.T., Scintillation proximity assays, in High Throughput Screening, The Discovery of Bioactive Substances, Devlin, J.P, Ed., Marcel Dekker, New York, 1997, chap. 16. 

Cook, N.D., Scintillation proximity assay a versatile high-throughput screening technology, Drug Discov. Today, 1, 287,2004. 

Bosworth, N., Towers, P. Scintillation proximity assay. Nature 1989, 341, 167-168. 

Heterogeneous radioactive assay with an extraction step Heterogeneous radioactive assay with an extraction step Scintillation proximity assay with beads or plates... 

Nare, B., Allocco, J.J., Kuningas, R., Galuska, S., Myers, R.W., Bednarek, M.A. and Schmatz, D.M. (1999) Development of a scintillation proximity assay for histone deacetylase using a biotinylated peptide derived from histone-H4. Analytical Biochemistry, 267, 390-396. 

Scintillation proximity assay (SPA) is a variety, or part, of RIA. This method is based on the measurement of the scintillation of radioactive molecules. On the basis of the power of the scintillation, it is possible to determine the amount of radioactivity. Then, it is possible to count the alkaloid content. This method was used recently in the biosynthesis of communesin alkaloids . ... 

The key to these assays is to find a suitable method by which the bound labeled ligand can be measured, separate from the unbound fraction. Three separate methods have been used to measure hERG binding filtration through glass fiber filters [36, 37], scintillation proximity assay (SPA) technology [38] and fluorescence... 

Values represent means s.e. mean of the number of experiments indicated in parentheses.3 Radioligand binding assay with 3H-DPCPX.b Radioligand binding assay with 3H-ZM 241385.° Reporter gene assay.d Scintillation proximity assay with 123I-AB-MECA (Press et al. 2005). 

The availability of MIP microparticles through this synthetic method has also stimulated the development of analytical techniques that make use of them as sensing elements. Apart from competitive radioassays [30] and immunoassays [32], which were already performed with ground bulk polymers, the small, regular size of the beads prepared by dispersion/precipitation polymerisation enables their use in CEC [45, 46], scintillation proximity assays [35], fluorescent polarisation assays [47], and chemiluminescence imaging [48]. 

Fig. 9 Schematic representation of the scintillation proximity assay of (S)-propanolol using imprinted microspheres. The light green area represents the aromatic antenna element, (a) The bound, tritium-labeled (S)-propranolol triggers the scintillator to generate a fluorescent light, (b) When the tritium-labeled (S)-propranolol is displaced by the unlabeled (S)-propranolol, it is too far away from the scintillator antenna to transfer efficiently the radiation energy therefore, no fluorescence can be generated (as described in [62])...

Lemer, C. G. and Saiki, A. Y. (1996) Scintillation proximity assay for human DNA topoisomerase I using recombinant biotinyl-fusion protein produced in baculo-virus-infected insect cells. Anal. Biochem. 240, 185-196. 

Method C. Most researchers have carried out CETP assay using a Scintillation Proximity Assay (SPA) kit [79]. The reaction mixtures containing a test sample, [3H]CE-HDL, and biotin-LDL, are thoroughly mixed. The reaction is initiated by the addition of CETP. After a 4-hr incubation at 37°C, the reaction is terminated by the addition of streptavidin SPA beads, and allowed to stand for 1 hr at room temperature. Finally, the transfer of [3H]CE from [3H]CE-HDL to LDL is measured by scintillation counter. 

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