Surface Plasmon Resonance Fluorescence Analysis Device And Surface Plasmon Resonance Fluorescence Analysis Method

Abstract

A surface plasmon fluorescence analysis device that has a chip holder, a light source, an angle adjustment unit, a light sensor, a filter holder, an excitation light cut filter, a scattered light transmission unit, a transmission adjustment unit, and a control unit. As seen in plan view, the area occupied by the scattered light transmission unit is arranged on the excitation light cut filter or on the filter holder and is smaller than the area of a fluorescence transmission region as seen in plan view.

1 . A surface plasmon resonance fluorescence analysis device to which an analysis chip including a dielectric having a metal film on one surface of the dielectric is attached and in which the metal film is irradiated with excitation light through the dielectric to excite a fluorescent material for labelling a detection target substance on the metal film, and then fluorescence emitted from the fluorescent material is detected to thereby detect the presence or amount of the detection target substance, the surface plasmon resonance fluorescence analysis device comprising:
 a chip holder configured to detachably hold the analysis chip;   an adjustable light source configured to emit excitation light at an incident angle with respect to the metal film to irradiate the metal film with the excitation light through the dielectric at an incident angle;   a light sensor configured to detect light emitted from the vicinity of a surface of the metal film, the surface facing away from the dielectric;   an excitation-light cut filter configured to allow fluorescence emitted from the metal film to pass through the filter and block at least light having a certain wavelength of the excitation light; and   an adjustable stage configured to tilt the excitation-light cut filter with respect to a normal line of a surface of the metal film such that plasmon scattering light emitted from the metal film is allowed to pass through;   wherein the chip holder is configured to hold the analysis chip in an orientation to allow the light emitted from the vicinity of the surface of the metal film to pass through the excitation-cut light filter to reach the light sensor.   
     
     
         2 . A surface plasmon resonance fluorescence analysis method in which fluorescence which is emitted by a fluorescent material for labelling a detection target substance when the fluorescent material is excited by localized-field light on a basis of surface plasmon resonance is detected to thereby detect the presence or amount of the detection target substance, the surface plasmon resonance fluorescence analysis method comprising:
 disposing the detection target substance on a metal film disposed on one surface of a dielectric;   adjusting an incident angle of excitation light with respect to the metal film;   while adjusting the incident angle of excitation light, irradiating the metal film with excitation light through the dielectric while a scattering-light transmitting hole is in a position where the plasmon scattering light is allowed to pass through the scattering-light transmitting hole,   wherein the scattering-light transmitting hole is formed at a filter holder or at an excitation light cut filter which includes a fluorescent transmitting region that allows fluorescence to pass through the region and blocks at least light having a certain wavelength of excitation light, the fluorescent transmitting region being defined by a second hole defined by the filter holder;   detecting the intensity of the plasmon scattering light that has been emitted from the metal film and has passed through the scattering-light transmitting hole while the metal film is irradiated with excitation light through the dielectric at the adjusted angles;   determining an enhanced angle that is an incident angle at which intensity of plasmon scattering light is maximized, based on the intensity of the detected plasmon scattering light;   irradiating the metal film with excitation light through the dielectric at the enhanced angle;   disposing the excitation-light cut filter at a position where light having a certain wavelength of the excitation light is blocked;   labelling the detection target substance disposed on the metal film with the fluorescent material; and   detecting the intensity of the fluorescence that has been emitted from the fluorescent material and has passed through the excitation-light cut filter, while the metal film is irradiated with the excitation light through the dielectric at the enhanced angle.