Methods and materials for optimization of electronic transportation and hybridization reactions

• US 20060065531A1
• Filed: 09/22/2005
• Published: 03/30/2006
• Est. Priority Date: 09/23/2004
• Status: Active Grant

• Current Assignee: Ador Diagnostics S.R.L., Nanogen, Inc.
• Original Assignee: Nanogen, Inc.
• Inventors: Hodko, Dalibor, Smolko, Daniel D., Swanson, Paul D., Haigis, Robert W., Canter, David, Patterson, Tricia
• Granted Patent: US 7,314,542 B2
• Time in Patent Office: Days
• US Class Current: 204/450
• CPC Class Codes: C12Q 1/6825 Nucleic acid detection involving sensors
• CPC Class Codes: C12Q 2565/607 being a sensor, e.g. electrode

Abstract

Methods for the transport and hybridization of a nucleic acid on an electrode device by providing a low conductivity buffer with a reducing agent to the device. The low conductivity buffer may also contain a zwitterion. A current and voltage is applied to a location of the device to effect electrophoretic transportation of the nucleic acid towards the location. The nucleic acid is then hybridized to a nucleic probed located at the location. The reducing agent in the low conductivity buffer may also be acting as a chaotropic agent.

Claims

1. A method for the transport of a nucleic acid to an electrode site comprising the steps of

providing a low conductivity, zwitterionic buffer with a reducing agent to the active electronic system;

applying current and voltage to an electrode to effect electrophoretic transportation of the nucleic acid towards the electrode.

2. The method of claim 1, further comprising the step of hybridizing the nucleic acid with a probe located at the electrode, whereby the local pH above the electrode is below the pH of the buffer at its isoelectric point.

3. The method of claim 1, wherein the reducing agent is α

-thioglycerol.

4. The method of claim 1, wherein the reducing agent is dithiotreitol.

5. The method of claim 1, wherein the reducing agent is β

-mercaptoethanol.

6. The method of claim 1, wherein a concentration of the reducing agent is about 25-500 mM.

7. The method of claim 1, wherein a concentration of the reducing agent is about 25 mM.

8. The method of claim 1, wherein a concentration of the reducing agent is about 125 mM.

9. The method of claim 1, wherein a concentration of the reducing agent is about 150 mM.

10. The method of claim 1, wherein a concentration of the reducing agent is about 250 mM.

11. The method of claim 1, wherein a concentration of the reducing agent is about 500 mM.

12. The method of claim 1, wherein the low conductivity, zwitterionic buffer is histidine.

13. The method of claim 12, wherein the low conductivity, zwitterionic buffer further comprises an additional zwitterion.

14. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains L-histidine.

15. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains D-histidine.

16. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains cysteine.

17. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains alanine.

18. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains lysine.

19. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains glutamic acid.

20. The method of claim 1, wherein the low conductivity, zwitterionic buffer contains γ

-aminobutyric acid.

21-107. -107. (canceled)