Magnetic sensor, production method of the same, and target substance detecting apparatus and biosensor kit using the same

• US 20070237673A1
• Filed: 04/04/2007
• Published: 10/11/2007
• Est. Priority Date: 04/11/2006
• Status: Abandoned Application

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Ikeda, Takashi, Okano, Kazuhisa
• Application Number:
  US11/730,778
• Publication Number:
  US 20070237673A1
• Time in Patent Office: Days
• US Class Current: 422/61
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: G01N 27/745 for detecting magnetic beads used in biochemical assays concerning the assays G01N33/54326; sensors therefor G01R33/1269; automatic analysers therefor G01N35/0098
• CPC Class Codes: G01R 33/093 using multilayer structures, e.g. giant magnetoresistance sensors thin magnetic films H01F10/00
• CPC Class Codes: G01R 33/1269 of molecules labeled with magnetic beads magnetic particles for bio assay G01N33/54326
• CPC Class Codes: Y10S 436/806 Electrical property or magnetic property

Abstract

The present invention provides a magnetic sensor which detects a target substance indirectly by making a labeling substance larger than the target substance bond with the target substance contained in a sample in a detection area, and detecting the labeling substance, comprising a capture area which is relatively easy to capture the target substance, and a non-capture area which is relatively hard to capture the target substance, on a surface of a member which is comprised in a detection area, wherein the capture area is surrounded by the non-capture area. Thereby, the sensor enables to detect comparatively accurately the number and concentration of substances which cannot be directly detected, and enables to be used for detection of various target substances.

Claims

1. A magnetic sensor which detects a target substance indirectly by making a labeling substance larger than the target substance bond with the target substance in a sample in a detection area, and detecting the labeling substance, comprising a capture area which is relatively easy to capture the target substance and a non-capture area which is relatively hard to capture the target substance on a surface of a member which is comprised in the detection area, wherein the capture area is surrounded by the non-capture area.

2. The magnetic sensor according to claim 1, wherein the non-capture area is dotted with the capture areas.

3. The magnetic sensor according to claim 2, wherein size of the capture area is sufficient for capturing the target substance, and insufficient for capturing a plurality of the target substances.

4. The magnetic sensor according to claim 3, wherein the capture areas are a distance larger than a diameter of the labeling substance apart.

5. The magnetic sensor according to claim 1, wherein the capture area is an area containing gold, and the non-capture area is an area containing silicon.

6. The magnetic sensor according to claim 5, wherein the area containing silicon is comprised of either silicon nitride or silicon oxide.

11. A detecting apparatus for detecting a target substance which comprises a magnetic sensor for detecting the target substance, and a detection unit for detecting a capture of the target substance on the magnetic sensor based on a signal obtained in the magnetic sensor,

wherein the magnetic sensor is a sensor according to claim 1;

and

wherein the detection unit has a unit of detecting capture of the target substance by comparing a signal obtained in the magnetic sensor with a reference value.

12. A kit for target substance detection, comprising a magnetic sensor according to claim 1 and a labeling substance.

7. A method for fabricating a magnetic sensor which has a capture area which is relatively easy to capture a target substance, and a non-capture area which surrounds the capture area and which is relatively hard to capture the target substance, on a surface of a member which is comprised in a detection area, and detects the target substance indirectly by making a labeling substance larger than the target substance bond with the target substance in a sample in the detection area, and detecting the labeling substance, comprising the steps of:

forming an aluminum film on a film comprised of a material which is comprised in the non-capture area;

anodizing the aluminum film to form a hole;

filling up the hole with a material which is comprised in the capture area; and

removing the aluminum film with leaving the filled area, and exposing the film comprised of the material which is comprised in the non-capture area.

8. A method for fabricating a magnetic sensor which has a capture area which is relatively easy to capture a target substance and a non-capture area which surrounds the capture area and which is relatively hard to capture the target substance on a surface of a member which is comprised in a detection area, and detects the target substance indirectly by making a labeling substance larger than the target substance bond with the target substance in a sample in the detection area, and detecting the labeling substance, comprising the steps of:

approaching a needle comprised of a material which is comprised in the capture area, to a film comprised of the material which is comprised in the non-capture area;

applying a voltage between the needle and the films; and

forming a dot, comprised of the material which is comprised in the capture area on the film comprised of the material which is comprised in the non-capture area.

9. A method for fabricating a magnetic sensor which has a capture area which is relatively easy to capture a target substance and a non-capture area which surrounds the capture area and which is relatively hard to capture the target substance on a surface of a member which is comprised in a detection area, and detects the target substance indirectly by making a labeling substance larger than the target substance bond with the target substance in a sample in the detection area, and detecting the labeling substance, comprising the steps of:

forming a hole in a resist film arranged on a film comprised of a material which is comprised in the non-capture area;

forming a material which is comprised in the capture area on the resist film to fill up the hole with the material which is comprised in the capture area; and

removing the resist film to expose the film comprised of the material which is comprised in the non-capture area.

10. A method for fabricating a magnetic sensor which has a capture area which is relatively easy to capture a target substance and a non-capture area which surrounds the capture area and which is relatively hard to capture the target substance on a surface of a member which is comprised in a detection area, and detects the target substance indirectly by making a labeling substance larger than the target substance bond with the target substance in a sample in the detection area, and detecting the labeling substance, comprising the steps of:

forming a film comprised of the material which is comprised in the non-capture area;

forming a hollow in the surface of the film; and

forming a material which is comprised in the capture area on the hollow.