1. The European Patent application 0 154 734 describes an immediate ligand detection assay that is marketed by Amersham Pharmacia Biotech as the SPA. See also: Udenfriend, S.; Gerber, L. D.; Brink, L.; Spector, S. Proc. Natl. Acad. Sci. USA 1985, 82, 8672–8676; Udenfriend, S.; Gerber, L. D.; Nelson, N. Analytical Biochem. 1987, 161, 494–500; Hoffman, R.; Cameron, L. Analytical Biochem. 1992, 203, 70–75.
2. Dyer, A. An Introduction to Liquid Scintillation Counting; Heyden: London, 1974; p. 12.
3. Amersham Life Science Catalogue, 1996; pp. 252–266.
4. Bosworth, N.; Towers, P. Nature 1989, 341, 167–168.
5. Sutherland, A. J.; Clapham, B., UK Patent application No. 9821662.5.