Scintillation proximity

Ye L, Mosbach K (2001) Polymers recognizing biomolecules based on a combination of molecular imprinting and proximity scintillation A new sensor concept. J Am Chem Soc 123 2901... 

In an approach with an external modifier that increases the fluorescence of the polymer, an external H-labeled template was used to generate the fluorescent signal through proximity scintillation [51]. The difference in this case is that the binding of H-labeled template gives a fluorescent complex, and its displacement by the analyte results in a decrease in fluorescence. Therefore, a scintillation monomer, 4-hydroxymethyl-2,5-diphenyloxazole acrylate (Fig. 9, 40), was incorporated into the imprinted polymer. Since (3 particles travel only a short distance, the 3 emission of... 

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

The membrane (or cell) preparation is added to the tubes to begin the binding reaction. The reagents are equilibrated for 30 to 90 minutes (time required for equilibration must be determined experimentally) and then the amount of bound ligand is quantified (either by separation or reading of scintillation proximity beads). The nsb and total binding are obtained from this experiment as shown (in bound pM). 

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. 

SPA is based on bringing a radioactive species in close proximity to a bead of solid scintillant. The technique relies on the specific capture of the substrate or product onto the bead so that the radioactivity can be measured without the need for separation. 

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... 

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