AGGREGATES OF PLURAL TRANSITION METAL NANOPARTICLES AND PLURAL CYANINE DYE MOLECULES

• US 20080316480A1
• Filed: 12/20/2007
• Published: 12/25/2008
• Est. Priority Date: 01/03/2007
• Status: Active Grant

• Current Assignee: The Research Foundation for The State University of New York (State University of New York)
• Original Assignee: The Research Foundation for The State University of New York (State University of New York)
• Inventors: ZHONG, Chuan-Jian, LIM, Stephanie I-Im
• Granted Patent: US 7,869,030 B2
• Time in Patent Office: Days
• US Class Current: 356/301
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 2021/6432 Quenching
• CPC Class Codes: G01N 21/6428 Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" in vivo A61B5/00; immunoassay G01N33/53
• CPC Class Codes: G01N 21/658 enhancement Raman, e.g. surface plasmons

Abstract

The present invention is directed to an aggregate composed of a plurality of nanoparticles of a transition metal and a plurality of cyanine dye molecules that are interacting non-covalently. The nanoparticles are capped with a capping molecule, while the cyanine dye molecule can be cationic, anionic, or neutral cyanine dye. Methods of making such aggregates and for using them in detection of an analyte are also disclosed.

Claims

1. A method of forming aggregates of nanoparticles and dyes, said method comprising:

providing nanoparticles of a transition metal, wherein the nanoparticles are capped with positive or negative capping groups;

providing cyanine dye molecules, which can be cationic, anionic, or neutral cyanine dye molecules; and

contacting the nanoparticles and the cyanine dye molecules under conditions effective to form aggregates of a plurality of the nanoparticles and a plurality of the dye molecules, wherein the nanoparticles and the cyanine dye molecules interact non-covalently.

2. The method of claim 1, wherein the transition metal is selected from the group consisting of copper, silver, gold, and mixtures thereof.

3. The method of claim 2, wherein the transition metal is gold.

4. The method of claim 1, wherein the cyanine dye is a cationic cyanine dye.

5. The method of claim 1, wherein the cyanine dye is a anionic cyanine dye.

6. The method of claim 1, wherein the cyanine dye is a neutral cyanine dye.

7. The method of claim 1, wherein the diameter of the nanoparticles is 1 to 100 nanometers.

8. The method of claim 1, wherein the aggregates are J-aggregates.

9. The method of claim 1, wherein the nanoparticles and dye molecules aggregate through an interaction selected from the group consisting of electrostatic interactions hydrophobic interaction, and π

-π

interaction.

10. The method of claim 1, wherein the capping groups are selected from the group consisting of acrylates, N,N-trimethyl(undecylmercapto)ammonium, tetrabutylammonium tetrafluoroborate, tetramethylammonium bromide, cetyltrimethylammonium bromide, citrates, polymethacrylate, ascorbic acid, DNA, 2-mercaptopropionic acid, 3-mercaptopropionic acid, 11-mercaptoundecanoic acid, 10-mercaptodecane-1-sulfonic acid, 16-mercaptohexadecanoic acid, diimide, N-(2-mercaptopropionyl)glycine (tiopronin), 2-mercaptoethanol, 4-mercapto-1-butanol, dodecyl sulfate, amino acids, homocysteine, homocystine, cysteine, cystine, and glutathione.

12. The aggregate of claim 1, wherein the transition metal is selected from the group consisting of copper, silver, gold, and mixtures thereof.

13. The aggregate of claim 12, wherein the transition metal is gold.

11. An aggregate of a plurality of nanoparticles of a transition metal, which are capped with a positive or negative capping group, and a plurality of cyanine dye molecules, which can be cationic, anionic or neutral cyanine dyes, wherein the nanoparticles and the cyanine dye molecules interact non-covalently.

14. The aggregate of claim 11, wherein the cyanine dye is a cationic cyanine dye.

15. The aggregate of claim 11, wherein the cyanine dye is a anionic cyanine dye.

16. The aggregate of claim 11, wherein the cyanine dye is a neutral cyanine dye.

17. The aggregate of claim 11, wherein the diameter of the nanoparticles is 1 to 100 nanometers.

18. The aggregate of claim 11, wherein the aggregates are J-aggregates.

19. The aggregate of claim 11, wherein the nanoparticles and dye molecules aggregate through an interaction selected from the group consisting of electrostatic interaction, hydrophobic interaction, and π

-π

interaction.

21. A method of detecting an analyte in a sample comprising:

providing a sample potentially containing the analyte;

providing the aggregate of claim 11;

contacting the sample with the aggregate; and

detecting a change in the aggregate caused by the analyte, whereby the detection of such a change permits detection of the analyte in the sample.

22. The method of claim 21, wherein said detecting comprises detecting a change by spectroscopy.

23. The method of claim 22, wherein the spectroscopy is selected from the group consisting of surface plasmon resonance spectroscopy, surface enhanced Raman scattering spectroscopy, fluorescence spectroscopy, and absorption spectroscopy.

20. A method of assembling aggregates of gold nanoparticles, said method comprising:

providing gold nanoparticles capped with positive or negative capping molecules;

providing cyanine dye molecules, which can be cationic, anionic, or neutral cyanine dyes; and

contacting the capped gold nanoparticles and the cyanine dye molecules under conditions effective to form aggregates of a plurality of the gold nanoparticles and a plurality of the cyanine dye molecules, wherein the cyanine dye molecules and the gold nanoparticles form J-aggregates and undergo hydrophobic interaction.