JP2008281470A - Device for measuring multichannel type surface plasmon resonance phenomenon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for measuring multichannel type surface plasmon resonance phenomenon that forms a prism on a sensor substrate by chemical etching to solve the botheration on operation caused by the introduction of the interface between the sensor substrate and the prism, and enter, by eliminating the affect of reflected light from places other than a sensing point and dividing beams emitted from a light source to improve an S/N ratio into N divisions equally with a beam splitter, them into only a sensing spot. <P>SOLUTION: The device for measuring multichannel type surface plasmon resonance phenomenon includes the light source for emitting beams, an optical system for dividing the light source into N divisions of the same light intensity and equal beams, an optical system for entering each beams divided into the N divisions simultaneously so as to line-focus on a substrate where a metallic thin film and the prism are formed and each sensing point on the substrate at a fixed angle, and a calculation section for extracting an electric signal of a detector to perform an operation and a comparison, which is small-sized and enables simultaneous multipoint-measurement. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a surface plasmon resonance phenomenon measuring apparatus (hereinafter referred to as an SPR measuring apparatus) capable of simultaneous measurement at multiple points.

  The SPR measuring device is an indispensable device for biochemical research as a biomolecular interaction analyzer (manufactured by Biacore, manufactured by Nippon Laser Co., Ltd.). However, the current ones are for research purposes only, and are not intended for on-site / field use, but are a category of expensive desktop physics and chemistry equipment.

  In the SPR measuring apparatus, in order to eliminate the refractive index change due to the temperature change of the sample, a temperature control unit for keeping the temperature of the sample constant is incorporated, which is one factor that makes the apparatus large and expensive. .

  As an improvement measure, for example, a differential SPR as disclosed in Japanese Patent Application Laid-Open No. 2004-340922 is provided. Here, the sensing point is divided into a blank and an object, and the difference between the signals is calculated to eliminate the error due to the temperature change of the sample.

  However, a PVC film is used as an interface between the sensor substrate and the prism and the sensor substrate is pressed against the PVC film, and the operation requires skill and skill. Furthermore, there is a problem that the measured signal varies depending on the degree of pressing.

  Further, since the light source is incident other than the sensing point, there is a problem that the background becomes high due to the influence of the reflected light.

JP2004-340922

  The problem to be solved by the present invention is to eliminate the troublesome operation due to the introduction of the interface between the sensor substrate and the prism, and to provide an SPR that anyone can easily operate. In addition, the influence of reflected light from other than the sensing point is eliminated as before, and the S / N ratio is improved.

  In the present invention, the prism is formed on the sensor substrate by chemical etching in order to eliminate the troublesome operation due to the introduction of the interface between the sensor substrate and the prism. Further, the beam emitted from the light source is equally divided into N by the beam splitter and incident only on the sensing spot, thereby eliminating noise as in the prior art and improving the S / N ratio.

The SPR measurement device of the present invention can be manufactured with a prism-integrated sensor substrate that does not require an interface, and by using this, the operability is greatly improved.
In addition, the beam splitter that can divide the light source equally into N allows light to be incident only on the sensing spot, which eliminates the reflected light from other than the sensing point that causes noise, and the S / N ratio of the signal obtained is improves.

    A light source that generates a beam, an optical system that divides the light source into N equal beams with the same light intensity, a substrate on which a metal thin film and a prism are formed, and each of the N divided beams, Computation and comparison by taking out the electrical signal of the detector and the optical system that makes the sensing point incident at a certain angle to form a line focus, the optical system that forms the reflected light from the metal thin film surface on the detector A surface plasmon resonance phenomenon measuring apparatus that has a calculation unit for performing the measurement and is small and capable of simultaneous measurement at multiple points.

  FIG. 1 is an arrangement of each part of the device of the present invention. The beam emitted from the light source 1 passes through the collimating lens 2 and becomes parallel light here.

  The parallel light is split into three non-polarized parallel lights having the same intensity by the beam splitter 3.

  These beams are reflected by the cylindrical lens 5 through the mirror 4 so as to form a line focus on the metal thin film surface formed on the prism-integrated sensor substrate 6.

  The path of the beam reflected on the metal thin film is changed by the mirror 7 and becomes parallel light by the cylindrical lens 8. Next, only the P-polarized light is transmitted through the polarizing plate 9 and is condensed on each detector 11 by the lens array 10.

  The signal of each detector is processed in the calculation unit 12 and a curve is output to the monitor.

  As described above, the metal thin film is patterned with N dots, and each of the beams divided by the beam splitter forms a line focus on each dot surface. Although this beam is reflected by the metal thin film surface, a phenomenon occurs in which the intensity of the reflected light at a certain incident angle is significantly reduced. This phenomenon is called a surface plasmon resonance phenomenon, and the incident angle at this time is called a resonance angle.

  For example, specific antibodies against various infectious disease pathogens are immobilized on the surfaces of N metal thin film dots by type. One of them is immobilized with an antibody that does not react with any pathogen, and is used as a blank. Here, if a specimen containing an unknown pathogen is placed on the metal foil membrane surface, the unknown pathogen specifically binds to any of the antibodies immobilized on the metal foil membrane dot surface by the antigen-antibody reaction. Thereafter, the specimen is removed, and a medium such as a phosphate buffer is placed instead, and the resonance angle becomes a large value only on the metal thin film dot surface on which the antibody to which the pathogen is bound is immobilized. If this is compared with the resonance angle of the blank, a shift amount of the resonance angle is obtained, and the larger the shift amount, the more the pathogen is bound to the antibody.

  That is, since it is already known which pathogen on the metal thin film dot pattern is immobilized, an unknown pathogen contained in the specimen can be identified.

  For example, since an infectious disease pathogen can be detected and identified, it can be used for infectious disease diagnosis.

FIG. 3 is a layout diagram of each part in a multi-channel surface plasmon resonance phenomenon measuring apparatus. Example 1

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 2 Collimating lens 3 Beam splitter 4 Mirror 5 Cylindrical lens 6 Prism integrated sensor board 7 Mirror 8 Cylindrical lens 9 Polarizing plate 10 Lens array 11 Detector 12 Calculation part

Claims (1)

  A light source that generates a beam; an optical system that divides the light source into equal beams with the same light intensity; a prism-integrated sensor substrate on which a metal thin film and a prism are formed; and each N-divided beam as a substrate An optical system that allows each of the sensing points above to enter a line focus at a fixed angle, an optical system that forms an image of reflected light from the metal thin film surface on the detector, and an electrical signal from the detector is extracted. A surface plasmon resonance phenomenon measuring apparatus that has a calculation unit for performing calculation and comparison, and is small and capable of simultaneous measurement at multiple points.

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