CAGED QUANTUM DOTS

• US 20110168975A1
• Filed: 07/06/2009
• Published: 07/14/2011
• Est. Priority Date: 07/07/2008
• Status: Abandoned Application

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Cohen, Bruce
• Application Number:
  US13/000,819
• Publication Number:
  US 20110168975A1
• Time in Patent Office: Days
• US Class Current: 257/13
• 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 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 2021/6439 with indicators, stains, dyes, tags, labels, marks
• 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

Abstract

Semiconductor nanocrystals known as quantum dots (QD) are caged by being associated with a molecule such as an orth-Nitrobenzyl (ONB) group. The luminescence of the QD is suppressed until activated by violet or ultra violet light.

Claims

1. A caged semiconductor nanocrystal, comprising:

a semiconductor nanocrystal; and

chemical moiety bound to or associated with the semiconductor nanocrystal, wherein the chemical moiety renders the semiconductor nanocrystal non-luminescent, and further wherein the chemical moiety is cleaved from the semiconductor nanocrystal by the application of violet or ultraviolet light.

2. The caged semiconductor nanocrystal as claimed in claim 1, wherein the chemical moiety is an aromatic group.

3. The semiconductor nanocrystal as claimed in claim 1, wherein, the chemical moiety is an ortho-nitrobenzyl (ONB) group.

4. The caged semiconductor nanocrystal of claim 1, wherein the semiconductor nanocrystal is comprised of a core and a shell.

5. The caged semiconductor nanocrystal of claim 4, wherein the core is comprised of CdTe and the shell is comprised of CdS.

6. The caged semiconductor nanocrystal of claim 3, wherein the ONB is covalently bound to the semiconductor nanocrystal.

7. The caged semiconductor nanocrystal of claim 1, wherein the semiconductor nanocrystal is comprised of Group II-VI semiconductors.

8. The caged semiconductor nanocrystal of claim 1, wherein the semiconductor nanocrystal is comprised of a semiconductor selected from the group consisting of MgS, MgSe, MgTe, CaS, CaSe, CaTe, SrS, SrSe, SrTe, BaS, BaSe, BaTe, ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, and HgTe.

9. The caged semiconductor nanocrystal of claim 1, wherein the semiconductor nanocrystal is comprised of Group III-V semiconductors.

10. The caged semiconductor nanocrystal of claim 1, wherein the semiconductor nanocrystal is comprised of a semiconductor selected from the group consisting of GaAs, InGaAs, InP, and InAs.

11. A caged semiconductor nanocrystal, comprising:

a semiconductor nanocrystal; and

an ortho-nitrobenzyl (ONB) covalently bound to the semiconductor nanocrystal, wherein the ONB group renders the semiconductor nanocrystal non-luminescent and further wherein exposing the caged semiconductor nanocrystal to light in a wavelength in a range of 300 nm to 420 nm cleaves the ONB from the semiconductor nanocrystal and renders the semiconductor nanocrystal luminescent.

12. A caged luminescent semiconductor nanocrystal compound capable of linking to an affinity molecule and capable of emitting electromagnetic radiation in a narrow wavelength band when excited, comprising:

a) a semiconductor nanocrystal capable of emitting light in a narrow wavelength band when excited;

b) a linking agent linked to said semiconductor nanocrystal and capable of linking to said affinity molecule; and

c) a chemical moiety associated with the semiconductor nanocrystal which moiety quenches luminescence from the semiconductor nanocrystal and is separable from the semiconductor nanocrystal by the application of light.

13. The caged luminescent semiconductor nanocrystal compound of claim 12, wherein said semiconductor nanocrystal is capable of absorbing energy over a wide bandwidth.

14. The caged luminescent semiconductor nanocrystal compound of claim 12, wherein said linking agent comprises a first portion linked to said semiconductor nanocrystal and a second portion capable of linking to said affinity molecule.