Naphthofluorescein-based metal sensors, and methods of making and using the same

1. A naphthofluorescein-based ligand, of the following structure:

wherein, independently for each occurrence:

A is a chemical moiety selected from the group consisting of —CH 2 —, —C(═O)—, —C(═S)—, and —C(H)═;

Q is O;

Y is O;

K is hydrogen; and

E is hydrogen.

2. The naphthofluorescein-based ligand of claim 1 , wherein A is —CH 2 —.

3. The naphthofluorescein-based ligand of claim 1 , wherein said ligand forms a tridentate or tetradentate chelating agent upon said complexation.

4. The naphthofluorescein-based ligand of claim 1 , wherein said ligand has the following structure:

wherein, independently for each occurrence:

K is hydrogen; and

E is hydrogen.

5. The naphthofluorescein-based ligand of claim 1 , wherein said ligand has the following structure:

wherein, independently for each occurrence:

K is hydrogen; and

E is hydrogen.

6. The naphthofluorescein-based ligand of claim 1 , wherein said ligand has the following structure:

wherein, independently for each occurrence:

K is hydrogen; and

E is hydrogen.

7. A coordination complex, comprising a metal ion coordinated to the naphthofluorescein-based ligands of any one of claims 2 , 3 , 4 , 5 , and 6 .

8. The coordination complex of claim 7 , wherein the metal ion is Zn 2+ .

9. The coordination complex of claim 7 , wherein the metal ion is Hg 2+ .

10. A naphthofluorescein-based scaffold, comprising a scaffold having the following structure:

wherein, independently for each occurrence:

Q is O;

Y is O;

W comprises one of the following: —CH 2 X, —C(O)H, —C(O)OR 2 , or —C(O)OH, wherein X is halogen, hydroxyl, amine, or thiol, and R 2 is alkyl;

K is hydrogen; and

E is hydrogen.

11. The naphthofluorescein-based scaffold of claim 10 , wherein said scaffold has one of the following structures:

wherein X is halogen, hydroxyl, amine, or thiol.