Detecting unit for detecting hybridization and other interactions and DNA chip and other bioassay substrates having the detecting unit

• US 20050112645A1
• Filed: 09/30/2004
• Published: 05/26/2005
• Est. Priority Date: 10/02/2003
• Status: Abandoned Application

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony International Europe Gmbh (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony International Europe Gmbh (Sony Group Corp.)
• Inventors: Segawa, Yuji, Harnack, Oliver, Mamine, Takayoshi
• Application Number:
  US10/955,280
• Publication Number:
  US 20050112645A1
• Time in Patent Office: Days
• US Class Current: 435/6
• CPC Class Codes: B03C 5/026 using open-gradient differential dielectric separation, i.e. using electrodes of special shapes for non-uniform field creation, e.g. Fluid Integrated Circuit [FIC]

Abstract

A detecting unit for detecting interaction between substances includes a pair of first opposed electrodes disposed opposite to each other so as to sandwich a reaction area providing a field for the interaction between the substances, and both or one of electrodes forming second opposed electrodes disposed opposite to each other in a direction of an axis crossing an opposing axis of the first opposed electrodes.

Claims

1. A detecting unit for detecting interaction between substances, said detecting unit comprising:

a pair of first opposed electrodes disposed opposite to each other so as to sandwich a reaction area providing a field for the interaction between the substances; and

both or one of electrodes forming second opposed electrodes disposed opposite to each other in a direction of an axis crossing an opposing axis of said first opposed electrodes.

2. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein the opposing axis of said second opposed electrodes is perpendicular to a surface on which a substance for detection is fixed in said reaction area.

3. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein said first opposed electrodes are means for drawing free substance and/or substance showing false interaction that are present in said reaction area to each electrode side by an electric field.

4. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein said second opposed electrodes are means for elongating a substance for detection fixed in said reaction area by an electric field.

5. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein said first opposed electrodes are means for drawing free substance and/or substance showing false interaction that are present in said reaction area to each electrode side by an electric field;

and

said second opposed electrodes are means for elongating a substance for detection fixed in said reaction area by an electric field.

6. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein said first opposed electrodes and said second opposed electrodes are electrodes for application of an alternating-current electric field.

7. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein an area of one of said second opposed electrodes is smaller than an area of the other opposite electrode.

8. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein a surface of at least one of said second opposed electrodes is formed into a rough surface.

9. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein at least one of said second opposed electrodes is formed by patterning.

10. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein said interaction is hybridization.

11. A detecting unit for detecting interaction between substances, as claimed in claim 1,

wherein surfaces of said electrodes are covered with an insulating layer.

12. A detecting unit for detecting interaction between substances, as claimed in claim 9,

wherein said insulating layer is formed by a material selected from SiO₂, SiN, SiOC, SiC, SiOF, and TiO₂.

13. A detecting unit for detecting interaction between substances, as claimed in claim 2,

wherein at least one of said second opposed electrodes is formed by a transparent conductor.

14. A detecting unit for detecting interaction between substances, as claimed in claim 3,

wherein nucleic acid as substance drawn to electrodes forming said first opposed electrodes is fixed on surfaces of said electrodes via one of an avidin-biotin bond and a disulfide bond.

15. A detecting unit for detecting interaction between substances, as claimed in claim 3,

wherein a surplus intercalator as substance drawn to electrodes forming said first opposed electrodes is trapped by a double stranded nucleic acid added in a vicinity of surfaces of said electrodes;

and

said double stranded nucleic acid is trapped on the surfaces of said electrodes via one of an avidin-biotin bond and a disulfide bond.

16. A detecting unit for detecting interaction between substances, as claimed in claim 3,

wherein a gel including cations and a gel including anions are made to be present in advance on surfaces of electrodes forming said first opposed electrodes;

and

a negatively charged nucleic acid and a positively charged surplus intercalator as substances drawn to each of said first opposed electrodes are electrostatically bonded to said cations and said anions, respectively.

17. A detecting unit for detecting interaction between substances, as claimed in claim 3,

wherein said detecting unit is a detecting unit for detecting hybridization between a nucleic acid for detection and a target nucleic acid present in said reaction area;

a single stranded nucleic acid having a base sequence complementary to one of a base sequence specific to said target nucleic acid and a base sequence modified at a terminal of said target nucleic acid is made to be present on surfaces of electrodes forming said first opposed electrodes; and

surplus target nucleic acid is trapped on the surfaces of said electrodes by hybridization between said single stranded nucleic acid and said surplus target nucleic acid.

18. A detecting unit for detecting interaction between substances, as claimed in claim 17,

wherein a surplus intercalator is trapped in one of a double stranded nucleic acid obtained by said hybridization and a double stranded nucleic acid added separately.

19. A detecting unit for detecting interaction between substances, as claimed in claim 3,

wherein substance drawn to electrodes forming said first opposed electrodes is decomposed by covering surfaces of the electrodes forming said first opposed electrodes with an insulating layer formed of TiO₂, irradiating said insulating layer with ultraviolet light, and making said TiO₂ function as a catalyst.

20. A bioassay substrate having the detecting unit for detecting interaction between substances as claimed in claim 1.

21. A bioassay substrate as claimed in claim 20,

wherein said interaction is hybridization.

22. A hybridization detecting unit comprising at least:

opposed electrodes for elongating nucleic acid as a complementary chain for hybridization; and

an electrode used for removing free nucleic acid present in a field of said hybridization and/or nucleic acid showing mis-hybridization.

23. A DNA chip having the detecting unit as claimed in claim 22.