Functionalized nanocrystals as visual tissue-specific imaging agents, and methods for fluorescence imaging

• US 6,333,110 B1
• Filed: 09/13/1999
• Issued: 12/25/2001
• Est. Priority Date: 11/10/1998
• Status: Expired due to Term

• Current Assignee: Life Technologies Corporation (Thermo Fisher Scientific Incorporated)
• Original Assignee: Bio-Pixels, Ltd.
• Inventors: Barbera-Guillem, Emilio
• Primary Examiner(s): Nutter, Nathan M.
• Application Number:
  US09/394,635
• Time in Patent Office: 834 Days
• Field of Search: 428/402.24, 428/404, 257/65, 257/614, 257/642, 424/9.1, 424/9.32, 424/9.36, 424/9.42, 424/9.6, 427/213.3, 427/214, 427/215, 427/220
• US Class Current: 428/402.24
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 5/00 Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery
• CPC Class Codes: C07F 3/06 Zinc compounds
• CPC Class Codes: C07F 3/08 Cadmium compounds
• CPC Class Codes: C12Q 1/6806 Preparing nucleic acids for analysis, e.g. for polymerase chain reaction [PCR] assay C12Q1/6804 takes precedence
• CPC Class Codes: Y10T 428/2989 Microcapsule with solid core [includes liposome]
• CPC Class Codes: Y10T 428/2993 Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]

Abstract

Provided is a method of fluorescence imaging of living tissue using functionalized nanocrystals. The method comprises contacting an effective amount of functionalized nanocrystals with the living tissue; exposing the tissue to a spectrum of light suitable for exciting functionalized nanocrystals, present in fluorescently labeled tissue, to emit a emission spectrum comprising a fluorescence peak; and detecting any fluorescence peak emitted by the tissue exposed to the excitation spectrum of light, and obtaining a fluorescence image of the tissue. Also provided is a composition comprising a functionalized nanocrystal which is bound to a substrate in a living tissue.

Claims

1. A functionalized nanocrystal bound to a substrate in a living tissue, wherein the functionalized nanocrystal comprises:

a quantum dot having a core and a shell;

a layer comprising capping compound operably linked to the quantum dot, wherein capping compound comprises a compound having the formula HS(CH₂)_nX, wherein X is a carboxylate;

a layer comprising a diaminocarboxylic acid which is operably linked to capping compound; and

affinity ligand which is operably linked to diaminocarboxylic acid.

2. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the core comprises CdX, and wherein X is Se, Te or S.

3. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the shell comprises YZ, and wherein Y is Cd or Zn, and Z is S, or Se.

4. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the capping compound is selected from the group consisting of a mercaptocarboxylic acid, a mercaptofunctionalized amine, aminoethanethiol-HCl, homocysteine, 1-amino-2-methyl-2-propanethiol-HCl, and a combination thereof.

5. The functionalized nanocrystal bound to a substrate according to claim 1, wherein diaminocarboxylic acid is selected from the group consisting of lysine, asparagine, glutamine, arginine, citrulline, ornithine, 5-hydroxylysine, djenkolic acid, β

-cyanoalanine, 3,4-diaminobenzoic acid, 2,3-diaminopropionic acid, 2,4-diaminobutyric acid, 2,5-diaminopentanoic acid, 2,6-diaminopimelic acid, and a combination thereof.

6. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the affinity ligand is selected from the group consisting of a lectin, a monoclonal antibody, a peptide, an aptamer, a nucleic acid molecule, avidin, streptavidin, and an avidin derivative.

7. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the functionalized nanocrystal further comprises an amino acid located between the diaminocarboxylic acid and the affinity ligand.

8. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the amino acid is selected from the group consisting of a monocarboxylic acid, and a diaminocarboxylic acid.

9. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the amino acid comprises a diaminocarboxylic acid, and the diaminocarboxylic acid is selected from the group consisting of lysine, asparagine, glutamine, arginine, citrulline, ornithine, 5-hydroxylysine, djenkolic acid, β

-cyanoalanine, 3,4-diaminobenzoic acid, 2,3-diaminopropionic acid, 2,4-diaminobutyric acid, 2,5-diaminopentanoic acid, 2,6-diaminopimelic acid, and a combination thereof.

10. The functionalized nanocrystal bound to a substrate according to claim 1, wherein the amino acid comprises a monoaminocarboxylic acid, and the monoaminocarboxylic acid is selected from the group consisting of glycine, serine, threonine, cysteine, β

-alanine, homoserine, γ

-aminobutyric acid, homocysteine, and a combination thereof.