Fluorescent metal sensors, and methods of making and using the same

• US 20030008405A1
• Filed: 04/17/2002
• Published: 01/09/2003
• Est. Priority Date: 04/17/2001
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Lippard, Stephen J., Burdette, Shawn
• Granted Patent: US 7,018,840 B2
• Time in Patent Office: Days
• US Class Current: 436/73
• CPC Class Codes: G01N 31/22 using chemical indicators G01N31/02 takes precedence
• CPC Class Codes: G01N 33/84 involving inorganic compounds or pH

Abstract

The present invention is directed, in part, to fluorescent metal sensors for detecting metal ions, and methods of making and using the same.

Claims

1. A ligand for metal ions, comprising the following moiety:

2. The ligand for metal ions of claim 1, wherein Q is OA, wherein A is hydrogen, alkyl, cycloalkyl, aryl, aryl, heterocycle, heterocycle or a hydroxyl protecting-group and Z forms a tautomer different from the tautomer formed when Q is O.

3. The ligand for metal ions of claim 1, wherein m is 2 and the two V'"'"'s form a ring structure with X.

4. The ligand for metal ions of claim 3, wherein said ligand for metal ion is sterically capable of forming four or more coordinate bonds to a single metal ion.

5. The ligand for metal ions of claim 1, wherein m is 2 and each of the V'"'"'s are capable of coordinating to a single metal ion through at least one nitrogen atom.

6. The ligand for metal ions of claim 1, wherein m is 2 and at least one of the V'"'"'s is capable of coordinating to a single metal ion through only one nitrogen atom.

7. A coordination complex, comprising a metal ion coordinated to a ligand for metal ions of claim 1.

8. A coordination complex, comprising a metal ion coordinated to a ligand for metal ions of claim 3.

9. The coordination complex of claim 7, wherein said metal ion is Zn²⁺.

10. The coordination complex of claim 8, wherein said metal ion is Zn²⁺.

11. A method of detecting, and optionally quantifying the concentration of, a metal ion in a sample, comprising:

a. measuring the fluorescence of one of the ligands for metal ions of claim 1 or claim 2 in the uncoordinated form;

b. measuring the fluorescence of said ligand in the presence of a metal ion; and

c. providing said ligand with instructions on how to determine whether said metal ion is present in a sample, and optionally said concentration of said metal ion in said sample, by comparing said measurements to a fluorescence measurement to be taken of said sample using said ligand.

12. A method of detecting, and optionally quantifying the concentration of, a metal ion in a sample, comprising:

a. adding to a sample one of the ligands for metal ions claimed in claim 1 or claim 2;

b. measuring the fluorescence of said ligand in said sample; and

c. determining whether said metal ion is present, and optionally said concentration of said metal ion, in said sample.

13. The method of claim 11, wherein said sample is a cell.

14. The method of claim 12, wherein said sample is a cell.

15. The method of claim 11, wherein said sample is in vitro.

16. The method of claim 12, wherein said sample is in vitro.

17. The method of claim 11, further comprising measuring the fluorescence of said ligand in the uncoordinated form at a different concentration of said ligand from said first measurement.

18. The method of claim 12, further comprising measuring the fluorescence of said ligand in said sample at a different concentration of said ligand.

19. The method of claim 11, wherein said metal ion is Zn²⁺.

20. The method of claim 12, wherein said metal ion is Zn²⁺.

21. The method of claim 11, wherein said sample contains a metal ion that is toxic to mammals.

22. The method of claim 12, wherein said sample contains a metal ion that is toxic to mammals.