Metal chelate containing compositions for use in chemiluminescent assays
Compositions are disclosed comprising (a) a metal chelate wherein the metal is selected from the group consisting of europium, terbium, dysprosium, samarium osmium and ruthenium in at least a hexacoordinated state and (b) a compound having a double bond substituted with two aryl groups, an oxygen atom and an atom selected from the group consisting of oxygen, sulfur and nitrogen wherein one of the aryl groups is electron donating with respect to the other. Such composition is preferably incorporated in a latex particulate material. Methods and kits are also disclosed for determining an analyte in a medium suspected of containing the analyte. The methods and kits employ as one component a composition as described above.
1. A method for determining the presence or amount of an analyte in a sample suspected of containing said analyte, said method comprising;
a) providing a combination comprising
1) said sample suspected of containing said analyte,
2) a photosensitizer capable in its excited state of activating oxygen to a singlet state, said photosensitizer being associated with a specific binding pair member that is capable of binding directly or indirectly to the analyte or competing with the analyte for a specific binding pair member, and
3) a composition comprising
i) a metal chelate comprising europium, terbium, dysprosium, samarium, osmium, or ruthenium, in at least a hexacoordinated state, and
ii) a compound having a structural portion that is a carbon-carbon double bond,
wherein one carbon of the carbon-carbon double bond is substituted with an aryl group and oxygen, wherein the other carbon of the carbon-carbon double bond is substituted with an aryl group and an oxygen, sulfur, or nitrogen,
wherein one of the aryl groups is electron donating with respect to the other,
said compound being associated with a specific binding pair member that is capable of binding directly or indirectly to the analyte or competing with the analyte for the specific binding pair member;
b) treating said combination with light or a reactive compound to excite said photosensitizer and cause it to form a singlet state of oxygen; and
c) detecting the amount of luminescence emitted from said combination, the presence or amount of said luminescence being related to the presence or amount of said analyte in said sample;
wherein the amount of luminescence is related to the amount of analyte in the medium.
2. The method of claim 1 , wherein said composition further comprises a particulate material.
3. The method of claim 2 , wherein the particulate material is a latex.
4. The method of claim 3 , wherein at least one of the components of said composition are associated with said latex particulate material.
5. The method of claim 3 , wherein all of the components of said composition are associated with said latex particulate material.
6. The method of claim 1 , wherein said photosensitizer is associated with a particulate material and at least one of said metal chelate and said compound is associated with a particulate material.
7. The method of claim 6 , wherein both of said metal chelate and said compound are associated with the same particulate material.
8. The method of claim 6 , wherein said particulate material is a latex.
9. The method of claim 6 , wherein each of said specific binding pair members is independently selected for each of said particulate materials.
10. The method of claim 1 , wherein each of said specific binding pair members is independently selected for each of said photosensitizer and said compound.
11. The method of claim 1 , wherein said compound reacts with said singlet state of oxygen, causing said compound to luminesce.
12. The method of claim 11 , wherein said metal chelate absorbs the luminescence emitted from said compound, and luminesces at a wavelength that is different than the wavelength of the luminescence emitted from said compound.
13. The method of claim 1 , wherein the compound has a structure represented by the following formula:
wherein X is O, S, or NR′, wherein R′ is alkyl or aryl, n is 1-4, and Ar and Ar′ are independently aryl, wherein one of Ar or Ar′ is electron donating with respect to the other and Y is hydrogen or an organic radical comprising C, O, N, S, or P, and m is 0-2.
14. The method of claim 13 , wherein said composition further comprises a particulate material.
15. The method of claim 14 , wherein the particulate material is a latex.
16. The method of claim 15 , wherein at least one of the components of said composition is associated with said latex particulate material.
17. The method of claim 15 , wherein all of the components of said composition are associated with said latex particulate material.
18. The method of claim 13 , wherein said photosensitizer is associated with a particulate material and at least one of said metal chelate and said compound are associated with at least one particulate material.
19. The method of claim 18 , wherein both of said metal chelate and said compound are associated with the same particulate material.
20. The method of claim 18 , wherein said particulate material is a latex.
21. The method of claim 18 , wherein each of said specific binding pair members is independently selected for each of said particulate materials.
22. The method of claim 13 , wherein each of said specific binding pair members is independently selected for each of said photosensitizer and said compound.
23. The method of claim 13 , wherein said compound reacts with said singlet state of oxygen, causing said compound to luminesce.
24. The method of claim 13 , wherein said metal chelate absorbs the luminescence emitted from said compound, and luminesces at a wavelength that is different than the wavelength of the luminescence emitted from said compound.
25. The method of claim 1 , wherein the compound has a structure represented by the following formula:
wherein X′ is O, S, or N, and the valency of N is completed with hydrogen or an organic radical comprising C, O, N, S, and P, and
wherein Ar and Ar′ are independently aryl, and one of Ar or Ar′ is electron donating with respect to the other, and
wherein the wavy lines are hydrogen or an organic radical, or wherein the wavy lines are taken together to form a ring,
said compound being capable of undergoing a chemical reaction with singlet oxygen to form a metastable intermediate that can decompose with the emission of light within the wavelength range of 250 to 1200 nm.
26. The method of claim 25 , wherein said composition further comprises a particulate material.
27. The method of claim 26 , wherein the particulate material is a latex.
28. The method of claim 27 , wherein at least one of the components of said composition is associated with said latex particulate material.
29. The method of claim 27 , wherein all of the components of said composition are associated with said latex particulate material.
30. The method of claim 25 , wherein said photosensitizer is associated with a particulate material and at least one of said metal chelate and said compound is associated with a particulate material.
31. The method of claim 30 , wherein both of said metal chelate and said compound are associated with the same particulate material.
32. The method of claim 30 , wherein said particulate material is a latex.
33. The method of claim 30 , wherein each of said specific binding pair members is independently selected for each of said particulate materials.
34. The method of claim 25 , wherein each of said specific binding pair members is independently selected for each of said photosensitizer and said compound.
35. The method of claim 25 , wherein said compound reacts with said singlet state of oxygen, causing said compound to luminesce.
36. The method of claim 35 , wherein said metal chelate absorbs the luminescence emitted from said compound, and luminesces at a wavelength that is different than the wavelength of the luminescence emitted from said compound.
37. The method of claim 1 , wherein the compound has a structure represented by the following formula:
wherein X″ is S or NR′, wherein R′ is alkyl or aryl, and D and D′ are independently selected from alkyl and alkyl radical groups.
38. The method of claim 37 , wherein said composition further comprises a particulate material.
39. The method of claim 38 , wherein the particulate material is a latex.
40. The method of claim 39 , wherein at least one of the components of said composition is associated with said latex particulate material.
41. The method of claim 39 , wherein all of the components of said composition are associated with said latex particulate material.
42. The method of claim 37 , wherein said photosensitizer is associated with a particulate material and at least one of said metal chelate and said compound is associated with a particulate material.
43. The method of claim 42 , wherein both of said metal chelate and said compound are associated with the same particulate material.
44. The method of claim 42 , wherein said particulate material is a latex.
45. The method of claim 42 , wherein each of said specific binding pair members is independently selected for each of said particulate materials.
46. The method of claim 37 , wherein each of said specific binding pair members is independently selected for each of said photosensitizer and said compound.
47. The method of claim 37 , wherein said compound reacts with said singlet state of oxygen, causing said compound to luminesce.
48. The method of claim 47 , wherein said metal chelate absorbs the luminescence emitted from said compound, and luminesces at a wavelength that is different than the wavelength of the luminescence emitted from said compound.