Method for gold deposition

• US 7,851,149 B2
• Filed: 08/11/2003
• Issued: 12/14/2010
• Est. Priority Date: 10/27/1998
• Status: Expired due to Fees

• Current Assignee: Erez Braun, Uri S. Sivan, Yoav Eichen
• Original Assignee: Erez Braun, Uri S. Sivan, Yoav Eichen
• Inventors: Braun, Erez, Eichen, Yoav, Sivan, Uri S
• Primary Examiner(s): Lam; Ann Y
• Application Number:
  US10/638,503
• Publication Number:
  US 20040033626A1
• Time in Patent Office: 2,682 Days
• Field of Search: 435/6, 435 71- 795, 435/4, 436512-548
• US Class Current: 435/5
• CPC Class Codes: C12Q 1/6834 Enzymatic or biochemical coupling of nucleic acids to a solid phase
• CPC Class Codes: C12Q 2527/127 the enzyme inhibitor or activator used
• CPC Class Codes: G01N 1/30 Staining; Impregnating ; Fixation; Dehydration; Multistep processes for preparing samples of tissue, cell or nucleic acid material and the like for analysis
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: G01N 33/585 with a particulate label, e.g. coloured latex

Abstract

A method for depositing gold on a substrate is provided. By this aspect, nucleation centers are bound, deposited or formed at one or more sites on the substrate, the substrate is then contacted with a treatment composition which comprises soluble gold-providing agent from which gold is deposited onto a nucleation center to yield gold metal deposits. The method of the invention may be used for a variety of image enhancing techniques as well as diagnostic and analyte detection techniques.

Claims

1. A method for detecting a target analyte in a sample, the method comprising:

(a) providing a non-conductive substrate having at least one pair of electrically conductive electrodes and a gap between the at least one pair of electrically conductive electrodes and at least one capturing agent that specifically binds to a binding site of the target analyte, the at least one capturing agent being immobilized on the surface of the substrate in the gap between the electrically conductive electrodes, the at least one capturing agent comprising an oligonucleotide that can bind to the binding site of the target analyte;

(b) forming a pretreated sample by adding a nucleation center containing a gold particle to said sample and providing conditions effective to couple the target analyte to the nucleation center;

(c) contacting the substrate and the pretreated sample under hybridizing conditions effective to bind the target analyte to the at least one capturing agent;

(d) adding a treatment composition to the substrate, the treatment composition comprising a gold providing agent and a reducing agent, whereby gold atoms are released from the gold providing agent and deposited on the nucleation center and wherein the treatment composition is kinetically stable so that gold atoms are not deposited unless a nucleation center is present; and

(e) determining one or more of the extent of an electrical contact between the electrodes or the existence of an electrical contact between the electrodes.

2. The method of claim 1, wherein the nucleation center includes a gold nanoparticle.

3. The method of claim 1, wherein the substrate further comprises an insulator between the electrically conductive electrodes.

4. The method of claim 1, wherein the target analyte is RNA or DNA.

5. The method of claim 1, wherein determining comprises measuring the conductivity between the electrically conductive electrodes.

6. The method of claim 1, wherein the target analyte is an oligonucleotide.

7. The method of claim 6, wherein the nucleation center includes a derivatized cluster.

8. The method of claim 7, wherein the nucleation center includes cis-platinum biotin.

9. The method of claim 8, wherein the derivatized cluster includes streptavidin.

10. The method of claim 9, wherein Au₅₅(Ph₃P)₁₂C₁₆ is bound to the streptavidin.

11. The method of claim 10, wherein the gold providing agent is a gold complex.

12. The method of claim 11, wherein the reducing agent is hyroquinone.

13. The method of claim 1, wherein the nucleation center includes a derivatized cluster.

14. The method of claim 13, wherein the nucleation center includes cis-platinum biotin.

15. The method of claim 14, wherein the derivatized cluster includes streptavidin.

16. The method of claim 15, wherein Au₅₅(Ph₃P)₁₂C₁₆ is bound to the streptavidin.

17. The method of 16, wherein the gold providing agent is a gold containing complex.

18. The method of claim 17, wherein the reducing agent is hyroquinone.