Method of immobilizing molecules onto a solid phase substrate and method of fabricating a biosensor using the method

• US 20050079528A1
• Filed: 08/27/2004
• Published: 04/14/2005
• Est. Priority Date: 09/11/2003
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Fukushima, Hitoshi, Takiguchi, Hiroshi
• Granted Patent: US 7,402,381 B2
• Time in Patent Office: Days
• US Class Current: 435/6
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 33/54353 with ligand attached to the carrier via a chemical coupling agent coatings G01N33/54393

Abstract

Aspects of the invention can provide a method capable of easily realizing immobilization with the optimum density derived from a concentration control and without phase separation in coadsorption of a number of molecules. The immobilization method can include the step of dissolving a plurality of molecules to be immobilized to a solid phase substrate with a solvent to obtain a solution of the plurality of molecules, and the step of incubating the solution and the solid phase substrate in touch therewith. Each of the molecules can include a solid phase substrate joint portion having a jointing property to the solid phase substrate, a functional portion having a specific function, and a linker portion positioned between the solid phase substrate joint portion and the functional portion.

Claims

1. An immobilization method, comprising:

dissolving a plurality of molecules that are to be immobilized to a solid phase substrate within a solvent so as to obtain a solution of the plurality of molecules; and

incubating the solution while keeping contact with the solid phase substrate,

each of the molecules including a solid phase substrate joint portion having a joining property to the solid phase substrate, a functional portion having a specific function, and a linker portion positioned between the solid phase substrate joint portion and the functional portion.

2. The immobilization method according to claim 1, the linker portion being derived from a compound selected from a group of polyethylene glycol, polypeptide, sugar, polyester, polyisocyanate, carbamic ester, and polyurethane.

3. The immobilization method according to one of claim 1, the solid phase substrate joint portion being a functional group capable of forming a self-assembled monomolecular film including the molecules.

4. The immobilization method according to claim 1, the plurality of molecules including a molecule having the functional portion composed of one of nucleic acid and protein.

5. The immobilization method according to claim 1, the plurality of molecules including a molecule having the functional portion composed of enzyme and enzyme mediator.

6. The immobilization method according to claim 1, the plurality of molecules including a molecule having the functional portion composed of at least one of a functional group and a compound,

the functional group being selected from a group of hydroxyl group, amino group, ferrocenyl group, and carboxyl group, and

the compound being selected from a group consisting of benzoquinone, N-methylphenazium, and biotin.

7. The immobilization method according to claim 1, a total concentration of the plurality of molecules in the solution being in a range from 0.3 to 5 μ

M.

8. A method of fabricating a biosensor including the immobilization method according to claim 1.

9. A biosensor, comprising:

a molecule composed mainly of a solid phase substrate joint portion;

a functional portion; and

a linker portion positioned between the solid phase substrate joint portion and the functional portion,

the molecule being joined to a solid phase substrate via the solid phase substrate joint portion.

10. The biosensor according to claim 9, the solid phase substrate being made of one of glass, polymer resin, carbon, metal, semiconductor, and metal oxide.

11. A method of detecting a target material in a test sample using the biosensor according to claim 9, comprising:

incubating the biosensor and the test sample in contact therewith using a gold deposited substrate as the solid phase substrate, the gold deposited substrate being made by depositing gold thin film on a surface of a glass substrate;

irradiating a light beam, continuously or intermittently around the incubating step, to the solid phase substrate of the biosensor from a surface opposite to a surface having the molecule immobilized thereto; and

measuring an alteration in an angle (resonance angle) with which a strength of reflected light corresponding to the light inputted thereto in the irradiating step is reduced.

12. A method of detecting a target material in a test sample using the biosensor according to claim 9, comprising:

incubating the biosensor and the test sample in contact therewith using a gold electrode of a crystal oscillator as the solid phase substrate; and

measuring an alteration in frequency of the crystal oscillator, continuously or intermittently, around the incubating step.