APPARATUS AND METHOD FOR DETECTING BIOMOLECULES

• US 20110165557A1
• Filed: 11/20/2008
• Published: 07/07/2011
• Est. Priority Date: 09/10/2008
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Park, Chan-Woo, Yu, Han-Young, Baek, In-Bok, Yang, HyeKyoung, Kim, Ansoon, Ahn, Chang-Geun, Ah, Chil-Seong, Park, Seon-Hee, Jang, Moon-Gyu, Sung, Gun-Yong, Yang, Jong-Heon, Kim, Taeyoub
• Granted Patent: US 8,529,750 B2
• Time in Patent Office: Days
• US Class Current: 435/5
• CPC Class Codes: B01L 2200/143 Quality control, feedback systems
• CPC Class Codes: B01L 2300/0636 Integrated biosensor, microarrays
• CPC Class Codes: B01L 2300/0645 Electrodes
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/163 Biocompatibility
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 3/502761 specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules investigating characteristics of particles G01N15/00
• CPC Class Codes: G01N 27/4145 specially adapted for biomolecules, e.g. gate electrode with immobilised receptors
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
• CPC Class Codes: Y10T 436/143333 Saccharide [e.g., DNA, etc.]

Abstract

Provided are an apparatus and method for detecting biomolecules. The apparatus includes a FET having a substrate, a source electrode, a drain electrode, a channel region between the source and drain electrodes, and probe molecules fixed to the channel region, wherein the source and drain electrodes are separated on the substrate, a microfluid supplier selectively supplying one of a reference buffer solution of low ionic concentration and a reaction solution of high ionic concentration containing target molecules, to the channel region of the FET to which the probe molecules are fixed, and a biomolecule detector detecting the target molecules by measuring a first current value of the channel region of the FET, and a second current value of the channel region of the FET to which the target molecules and the probe molecules that bind to each other in the reaction solution of high ionic concentration are fixed.

Claims

1. An apparatus for detecting biomolecules, comprising:

a field effect transistor (FET) comprising a substrate, a source electrode, a drain electrode, a channel region between the source and drain electrodes, and probe molecules fixed to the channel region, wherein the source and drain electrodes are space apart from each other on the substrate;

a microfluid supplier selectively supplying one of a reference buffer solution of low ionic concentration and a reaction solution of high ionic concentration containing target molecules, to the channel region of the FET to which the probe molecules are fixed; and

a biomolecule detector detecting the target molecules by measuring a first current value of the channel region of the FET to which the probe molecules are fixed, and a second current value of the channel region of the FET to which the target molecules and the probe molecules that bind to each other in the reaction solution of high ionic concentration are fixed.

2. The apparatus of claim 1, wherein the first and second current values are measured by supplying the reference buffer solution of low ionic concentration to the channel region of the FET.

3. The apparatus of claim 2, wherein the biomolecule detector detects the target molecule according to a difference between the first and second current values.

4. The apparatus of claim 1, wherein the microfluid supplier selectively supplies one of the reference buffer solution of low ionic concentration, the reaction solution of high ionic concentration containing the target molecules, and a stabilization solution.

5. The apparatus of claim 4, wherein the reaction solution of high ionic concentration includes blood, blood serum, blood plasma, urine, saliva, or a high ionic concentration solution, which contains the target molecules.

6. The apparatus of claim 4, wherein the stabilization solution is a buffer solution having an ionic strength or an ion similar to the reaction solution of high ionic concentration.

7. The apparatus of claim 4, further comprising a controller controlling supply durations of the reference buffer solution of low ionic concentration, the reaction solution of high ionic concentration containing the target molecules, and the stabilization solution.

8. The apparatus of claim 1, wherein the microfluid supplier comprises:

a plurality of fluid channels supplying the respective solutions; and

a joint channel connecting the plurality of fluid channels to the channel region of the FET.

9. The apparatus of claim 1, wherein the channel region of the FET comprises an impurity-doped layer, a semiconductor layer, an oxide layer, a compound layer, a carbon nanotube (CNT), or a semiconductor nanowire.

10. A method for detecting biomolecules, the method comprising:

providing a FET comprising a substrate, a source electrode, a drain electrode, a channel region between the source and drain electrodes, and probe molecules fixed to the channel region, wherein the source and drain electrodes are space apart from each other on the substrate;

supplying a reference buffer solution of low ionic concentration to the channel region to which the probe molecules are fixed, and measuring a first current value flowing through the channel region;

binding the target molecules to the probe molecules by supplying a reaction solution of high ionic concentration containing the target molecules to the channel region to which the probe molecules are fixed;

removing the reaction solution of high ionic concentration after reaction by supplying the reference buffer solution of low ionic concentration to the channel region where the target molecules bind to the target molecules, and measuring a second current value flowing through the channel region in the reference buffer solution of low ionic concentration; and

detecting the target molecules using a difference between the first and second current values.

11. The method of claim 10, further comprising, before the measuring of the first current value, supplying a reference buffer solution of low ionic concentration, and supplying a stabilization solution.

12. The method of claim 11, wherein the supplying of the reference buffer solution of low ionic concentration and the supplying the stabilization solution are repeated once or more.

13. The method of claim 11, wherein the reaction solution of high ionic concentration includes blood, blood serum, blood plasma, urine, saliva, or a high ionic concentration solution, which contains the target molecules.

14. The method of claim 11, wherein the stabilization solution has an ionic strength or an ion similar to the reaction solution of high ionic concentration.

15. The method of claim 11, wherein the measuring of the first or second current value of the channel region comprises measuring a saturation current of the channel region after supplying the reference buffer solution of low ionic concentration.

16. The method of claim 10, wherein the channel region of the FET comprises an impurity-doped layer, a semiconductor layer, an oxide layer, a compound layer, a metal layer, a carbon nanotube (CNT), or a semiconductor nanowire.

17. The method of claim 10, wherein the probe molecule or the target molecule is selected from the group consisting of a nucleic acid, a cell, a virus, a protein, an organic molecule, an inorganic molecule, and a biomolecule.

18. The method of claim 17, wherein the nucleic acid is selected from the group consisting of DNA, RNA, PNA, LNA, and hybrids thereof.

19. The method of claim 17, wherein the protein is selected from the group consisting of an enzyme, a substrate, an antigen, an antibody, a ligand, an aptamer, and a receptor.

20. The method of claim 17, wherein the binding of the target molecules to the probe molecules comprises a nucleic acid hybridization, an antigen-antibody reaction, an enzyme binding reaction.