Scintillation proximity test

Abstract

The invention concerns scintillation proximity assays performed in multiwell plates where a charge coupled device is used to image the wells. Conventional phosphors emit blue light (350-450 nm) which is absorbed by yellow or brown assay components. This problem is addressed by the use of phosphors that emit radiation of longer wavelength (480-900 nm).

1 - 10 . (canceled)  
   
   
       11 . In a scintillation proximity method which uses a phosphor for detection, which method comprises the steps of: 
 contacting a surface carrying said phosphor with a body of fluid containing a radioisotope to provide a reaction mixture;    incubating said reaction mixture under conditions to allow binding of the radioisotope to the surface; and    detecting radiation emitted by the phosphor;    the improvement comprising using a phosphor that has an emission maximum of 530 nm-640 nm and a cooled charge coupled device for detecting radiation emitted by the phosphor as part of the detection system.    
   
   
       12 . The method of  claim 11 , wherein the phosphor has an emission maximum of 540 nm-630 nm.  
   
   
       13 . The method of  claim 11 , wherein the phosphor has an emission maximum of 550 nm-620 nm.  
   
   
       14 . The method of  claim 11 , wherein the scintillation proximity test is performed in wells of a multiwell plate.  
   
   
       15 . The method of  claim 14 , wherein the charge coupled device is used to simultaneously image all the wells of the multiwell plate.  
   
   
       16 . The method of  claim 11 , wherein the phosphor is an inorganic host material doped with an activator which is a lanthanide or actinide moiety.  
   
   
       17 . The method of  claim 11 , wherein the phosphor is an organic chelate of a lanthanide or actinide moiety.  
   
   
       18 . The method of  claim 16 , wherein the lanthanide or actinide moiety is selected from the group consisting of terbium, europium, erbium, thulium, holmium, dysprosium, samarium, ytterbium, lutecium, gadolinium, uranium and uranyl UO 2   3+ .  
   
   
       19 . The method of  claim 16 , wherein the lanthanide moiety is terbium or europium.  
   
   
       20 . The method of  claim 16 , wherein the lanthanide moiety is Europium and the phosphor has an emission maximum of 535 nm-565 nm.  
   
   
       21 . The method of  claim 16 , wherein the lanthanide moiety is Terbium and the phosphor has an emission maximum of 605 nm-625 nm.  
   
   
       22 . The method of  claim 17 , wherein the phosphor is an organic chelate of Europium or Terbium.  
   
   
       23 . The method of  claim 22 , wherein the phosphor is an organic chelate of Europium and has an emission maximum of 535 nm-565 nm.  
   
   
       24 . The method of  claim 22 , wherein the phosphor is an organic chelate of Terbium and has an emission maximum of 605 nm-625 nm.  
   
   
       25 . A method of performing a scintillation proximity test comprising: 
 providing a solid surface comprising a phosphor in a fluid medium,    causing a radiolabelled reagent to become divided into two fractions one bound to the solid surface and the other in the fluid medium, and    detecting the fraction of the radiolabelled reagent bound to the solid surface,    characterised by using a phosphor that has an emission maximum of 530 nm-640 nm and a cooled charge coupled device for detecting radiation emitted by the phosphor.    
   
   
       26 . The method of  claim 25 , wherein the phosphor has an emission maximum of 540 nm-630 nm.  
   
   
       27 . The method of  claim 25 , wherein the phosphor has an emission maximum of 550 nm-620 nm.  
   
   
       28 . The method of  claim 25 , wherein the scintillation proximity test is performed in wells of a multiwell plate.  
   
   
       29 . The method of  claim 28 , wherein the charge coupled device is used to image simultaneously all the wells of the multiwell plate.  
   
   
       30 . The method of  claim 25 , wherein the phosphor is an inorganic host material doped with an activator which is a lanthanide or actinide moiety.  
   
   
       31 . The method of  claim 25 , wherein the phosphor is an organic chelate of a lanthanide or actinide moiety.  
   
   
       32 . The method of  claim 30 , wherein the lanthanide or actinide moiety is selected from the group consisting of terbium, europium, erbium, thulium, holmium, dysprosium, samarium, ytterbium, lutecium, gadolinium, uranium and uranyl UO  2   3+ .  
   
   
       33 . The method of  claim 30 , wherein the lanthanide moiety is terbium or europium.  
   
   
       34 . The method of  claim 30 , wherein the lanthanide moiety is Europium and the phosphor has an emission maximum of 535 nm-565 nm.  
   
   
       35 . The method of  claim 30 , wherein the lanthanide moiety is Terbium and the phosphor has an emission maximum of 605 nm-625 nm.  
   
   
       36 . The method of  claim 25 , wherein the phosphor is an organic chelate of Europium or Terbium.  
   
   
       37 . The method of  claim 36 , wherein the phosphor is an organic chelate of Europium and has an emission maximum of 535 nm-565 nm.  
   
   
       38 . The method of  claim 36 , wherein the phosphor is an organic chelate of Terbium and has an emission maximum of 605 nm-625 nm.