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

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.

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. 
     
     
         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.   
     
     
         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.