Nucleic acid mediated electron transfer

• US 5,952,172 A
• Filed: 06/12/1997
• Issued: 09/14/1999
• Est. Priority Date: 12/10/1993
• Status: Expired due to Term

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Kayyem, Jon Faiz, Meade, Thomas J., Fraser, Scott E.
• Primary Examiner(s): ZITOMER, STEPHANIE W
• Application Number:
  US08/873,598
• Time in Patent Office: 824 Days
• Field of Search: 435/6, 536/24.31, 536/24.32, 536/24.3, 935/77, 935/78
• US Class Current: 435/6.11
• CPC Class Codes: C07H 21/00 Compounds containing two or more mononucleotide units having separate phosphate or polyphosphate groups linked by saccharide radicals of nucleoside groups, e.g. nucleic acids
• CPC Class Codes: C07H 23/00 Compounds containing boron, silicon, or a metal, e.g. chelates, vitamin B12 esters with inorganic acids C07H11/00; metal salts, see parent compounds
• CPC Class Codes: C12Q 1/6818 involving interaction of two or more labels, e.g. resonant energy transfer
• CPC Class Codes: C12Q 1/6825 Nucleic acid detection involving sensors
• CPC Class Codes: C12Q 2563/113 the label being electroactive, e.g. redox labels
• CPC Class Codes: C12Q 2563/137 Metal/ion, e.g. metal label
• CPC Class Codes: C12Q 2565/101 Interaction between at least two labels
• CPC Class Codes: C12Q 2565/1015 labels being on the same oligonucleotide
• CPC Class Codes: C12Q 2565/401 Signal amplification by chemical polymerisation
• CPC Class Codes: C12Q 2565/607 being a sensor, e.g. electrode
• CPC Class Codes: Y02A 50/30 Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change

Abstract

The present invention provides for the selective covalent modification of nucleic acids with redox active moieties such as transition metal complexes. Electron donor and electron acceptor moieties are covalently bound to the ribose-phosphate backbone of a nucleic acid at predetermined positions. The resulting complexes represent a series of new derivatives that are bimolecular templates capable of transferring electrons over very large distances at extremely fast rates. These complexes possess unique structural features which enable the use of an entirely new class of bioconductors and photoactive probes.

Claims

1. A method for detecting the presence of a target sequence in a nucleic acid sample, comprising:

a) applying an AC input signal to a hybridization complex, wherein said hybridization complex comprises

i) a first single stranded nucleic acid containing at least one covalently attached electron transfer moiety and an electrode; and

ii) a target single stranded nucleic acid;

b) detecting the presence of said target sequence via an output signal characteristic of electron transfer between said electrode and said electron transfer moiety.

3. A method according to claim 1 or 2 wherein at least one of said electron transfer moieties is a transition metal complex.

4. A method according to claim 1 or 2 wherein at least one of said electron transfer moieties is an organic electron transfer moiety.

5. A method according to claim 1 or 2 wherein the AC input signal is applied at a plurality of frequencies.

6. A method according to claim 1 or 2 wherein said output signal comprises a current.

7. A method according to claim 1 or 2 wherein said output signal is time delayed as compared to said input signal.

8. A method according to claim 1 or 2 wherein said nucleic acid comprises a ribose-phosphate backbone and said electron transfer moiety is covalently attached to a ribose of the ribose-phosphate backbone.

9. A method according to claim 1 or 2 wherein said nucleic acid comprises a ribose-phosphate backbone and said electron transfer moiety is covalently attached to a phosphate of the ribose-phosphate backbone.

10. A method according to claim 1 or 2 wherein said electron transfer moiety is covalently attached to a terminal base.

2. A method for detecting the presence of a target sequence in a nucleic acid sample, comprising:

a) applying an AC input signal to a hybridization complex, wherein said hybridization complex comprises

i) a first single stranded nucleic acid containing at least one covalently attached electron transfer moiety; and

ii) a second single stranded nucleic acid containing an electrode; and

b) detecting the presence of said target sequence via an output signal characteristic of electron transfer between said electrode and said electron transfer moiety.

11. A method for detecting the presence of a target sequence in a nucleic acid sample, comprising:

a) applying an AC input signal at a first frequency to a hybridization complex, wherein said hybridization complex comprises

i) a first single stranded nucleic acid containing at least one covalently attached electron transfer moiety and an electrode; and

ii) a target single stranded nucleic acid;

b) applying an AC input signal at at least a second frequency to said hybridization complex;

c) detecting the presence of said target sequence via an output signal characteristic of electron transfer between said electrode and said electron transfer moiety.