Provided herein are compositions of functionalized, fluorescent nanocrystals comprising fluorescent nanocrystals coated with an imidazole-containing compound; compositions of functionalized, fluorescent nanocrystals comprising fluorescent nanocrystals coated with an imidazole-containing compound and cross-linked with a phosphine cross-linking compound; compositions of functionalized fluorescent nanocrystals operably bound to molecular probe; a process of making functionalized, fluorescent nanocrystals; and a process of using functionalized, fluorescent nanocrystals in a detection system.
1. A functionalized fluorescent nanocrystal comprised of:
a fluorescent nanocrystal; and
an imidazole-containing capping layer wherein the capping layer further comprises a phosphine cross-linking compound.
2. The functionalized fluorescent nanocrystal of claim 1 , wherein the fluorescent nanocrystal comprises a core semiconductor nanocrystal, a core/shell semiconductor nanocrystal, a doped metal oxide nanocrystal, or a mixture thereof.
3. The functionalized fluorescent nanocrystal of claim 2 , wherein the fluorescent nanocrystal is a core nanocrystal co-precipitated with a metal salt shell.
4. The functionalized fluorescent nanocrystal of claim 3 , wherein the metal salt shell comprises a semiconductor material with a higher band gap energy than the core nanocrystal.
5. The functionalized fluorescent nanocrystal of claim 3 , wherein the core nanocrystal comprises a Group II-VI semiconductor and the metal salt shell comprises a Group II-VI semiconductor.
6. The functionalized fluorescent nanocrystal of claim 3 , wherein the core nanocrystal comprises a Group II-VI semiconductor and the metal salt shell comprises a compound comprising sulfur and a metal selected from the group consisting of zinc, copper, iron, nickel, cadmium, cobalt, and mixtures thereof.
7. The functionalized fluorescent nanocrystal of claim 3 , wherein the core nanocrystal comprises cadmium selenide and the metal salt shell comprises zinc sulfide.
8. The functionalized fluorescent nanocrystal of claim 3 , wherein the imidazole-containing capping layer comprises a functional group comprising an ion operably bound to the metal salt shell.
9. The functionalized fluorescent nanocrystal of claim 3 , wherein the imidazole-containing capping layer comprises a nitrogen operably bound to the metal salt shell.
10. The functionalized fluorescent nanocrystal of claim 3 , wherein the capping layer is uniformly deposited over an outer surface of the fluorescent nanocrystal.
11. The functionalized fluorescent nanocrystal of claim 3 , wherein the imidazole-containing capping layer passivates the fluorescent nanocrystal.
12. The functionalized fluorescent nanocrystal of claim 3 , wherein the fluorescence intensity of the functionalized fluorescent nanocrystal is greater than the fluorescence intensity of a non-functionalized fluorescent nanocrystal.
13. The functionalized fluorescent nanocrystal of claim 3 , wherein the fluorescence intensity of the functionalized fluorescent nanocrystal is enhanced up to about 1100 fold when compared to a non-functionalized fluorescent nanocrystal.
14. The functionalized fluorescent nanocrystal of claim 3 , wherein the fluorescence intensity of the functionalized fluorescent nanocrystal is enhanced about 30 to about 300 fold when compared to a non-functionalized fluorescent nanocrystal.
15. The functionalized fluorescent nanocrystal of claim 3 , wherein the fluorescence intensity of the functionalized fluorescent nanocrystal is enhanced about 10 to about 100 fold when compared to a non-functionalized fluorescent nanocrystal.
16. The functionalized fluorescent nanocrystal of claim 3 , wherein the imidazole-containing capping layer is cross-linked.
17. The functionalized fluorescent nanocrystal of claim 3 , wherein the functionalized fluorescent nanocrystal is soluble in aqueous solutions.
18. The functionalized fluorescent nanocrystal of claim 3 , wherein the functionalized fluorescent nanocrystal is stable in aqueous solutions at about pH 6 to about pH 10.5.
19. The functionalized fluorescent nanocrystal of claim 3 , wherein the functionalized fluorescent nanocrystal is stable in aqueous solutions at about pH 7 to about pH 9.
20. The functionalized fluorescent nanocrystal of claim 3 , wherein the functionalized fluorescent nanocrystal is stable in aqueous solutions at about pH 8 to about pH 10.
21. The functionalized fluorescent nanocrystal of claim 3 , wherein the functionalized fluorescent nanocrystal is operably bound to a molecular probe.
22. A method for detecting a target molecule, the method comprising:
forming a complex by operably bonding a functionalized fluorescent nanocrystal to a target molecule, wherein the functionalized fluorescent nanocrystal comprises an imidazole-containing capping layer wherein the capping layer further comprises a phosphine cross-linking compound;
exciting the complex; and
detecting light emitted from the complex.