Luminescent nanomaterials

• US 20050013999A1
• Filed: 11/01/2002
• Published: 01/20/2005
• Est. Priority Date: 11/01/2001
• Status: Abandoned Application

• Current Assignee: Oxonica Limited
• Original Assignee: Oxonica Limited
• Inventors: Green, Mark, Wakefield, Gareth
• Application Number:
  US10/494,128
• Publication Number:
  US 20050013999A1
• Time in Patent Office: Days
• US Class Current: 428/403
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: Y10T 428/2991 Coated

Abstract

A process is disclosed for preparing water soluble particles of a luminescent material which is a rare earth material, a doped compound semi-conductor or a doped inorganic compound which comprises coating particles of said luminescent material, either during production of the particles, or subsequently, with an organic acid or Lewis base such that the surface of the coating possesses one or more reactive groups.

Claims

1. A process for preparing water soluble particles of a luminescent material which is a rare earth material, a doped compound semi-conductor or a doped inorganic compound which comprises coating particles of said luminescent material, either during production of the particles, or subsequently, with an organic acid or Lewis base such that the surface of the coating possesses one or more reactive groups.

2. A process according to claim 1 wherein the reactive groups are —

SH, —

COOH, —

OH, amino or amido groups.

3. A process according to claim 1 or 2 wherein the rare earth material is a rare earth metal oxide or an inorganic compound which has been doped with a rare earth element.

4. A process according to any one of the preceding claims wherein the rare earth metal is europium, terbium, cerium, yttrium, scandium, lanthanum or gadolinium.

5. A process according to any one of the preceding claims wherein the doped material is a doped rare earth oxide of the formula Z₂O₃:

Z^x+ where Z is a rare earth metal and x is from 2 to 4.

6. A process according to any one of claims 1 to 4 wherein the inorganic compound is a rare earth metal oxide, a fluoride, oxyhalide, borate, aluminate, silicate, phosphate, vanadate, oxysulphide, tungstate, molybdate or uranyl compound.

7. A process according to claim 1 or 2 wherein the dopant of the doped compound semi-conductor or inorganic compound is a rare earth material or a first row transition metal or a Group IIA metal of the Periodic Table.

8. A process according to claim 7 wherein the dopant is a rare earth metal as defined in claim 4, manganese, copper, chromium, calcium or strontium.

9. A process according to claim 7 or 8 wherein the compound semi-conductor is a Group II/Group VI or Group III/Group V semi-conductor.

10. A process according to any one of the preceding claims wherein the coating is applied to a preformed rare earth material which possesses a surface coating of an organic acid or Lewis base and a coating of a water soluble organic acid or Lewis base to provide the reactive group on the surface of the particles is applied from aqueous solution.

11. A process according to any one of claims 1 to 9 wherein the coating is applied during the production of the particles.

12. A process according to claim 11 for the production of particles as claimed in claim 5 which comprises adding a metal surface active molecule which has a surface capping effect to a solution of a rare earth metal salt and adding alkali so as to cause a colloidal precipitate to form.

13. A process according to any one of the preceding claims wherein the coating is a ligand which is monodentate, bidentate or polydentate.

14. A process according to claim 13 wherein the ligand is a trialkylphosphine oxide, or a dialkyl sulphosuccinate, a polymer possessing phosphonic and carboxylic acid groups, or a nucleoside phosphate.

15. A process according to any one of the preceding claims wherein the particles have a size which does not exceed 10 microns.

16. A process according to claim 15 wherein the particles have a size from 10 nm to 1 micron.

17. A process according to claim 1 substantially as described in any one of the Examples.

18. Water soluble particles of a luminescent material whenever prepared by a process as claimed in any one of the preceding claims.

28. A biotag which comprises particles as claimed in any one of claims 18 to 27 attached to one member of a ligand binding pair.

29. A biotag according to claim 28 wherein the ligand binding pair is avidin and biotin or an antibody or an antigen.

30. A biotag according to claim 28 substantially as hereinbefore described.

31. A process for tagging a moiety which comprises attaching a biotag as claimed in any one of claims 28 to 30 either directly or after attaching to said moiety the other member of said ligand binding pair.

32. A process according to claim 31 wherein the biotag is produced with the aid of a cross linking agent.

33. A process according to claim 31 substantially as hereinbefore described.

19. Water soluble particles of a luminescent material which is a rare earth material, a doped semi-conductor or a doped inorganic compound, possessing a coating with one or more reactive groups on the surface of said coating.

20. Particles according to claim 19 wherein the reactive groups are —

SH, —

COOH, —

OH, amino or amido groups.

21. Particles according to claim 19 or 20 which are of a rare earth material.

22. Particles according to claim 21 which have one or more of the features of claims 3 to 5.

23. Particles according to claim 19 or 20 which are of a Group II/Group VI or Group III/Group V semi-conductor.

24. Particles according to claim 19 or 20 which are of a doped inorganic compound.

25. Particles according to claim 23 or 24 which have one or more of the features of claims 6 to 8.

26. Particles according to claim 19 of Tb₂O₃ or Eu₂O₃ coated with a copolymer of acrylic acid and vinyl phosphonic acid.

27. Particles according to claim 19 of europium tungstate coated with adenosine 5′

-triphosphate.