Analysis method and analysis apparatus

Abstract

Provided are an analysis method and an analysis apparatus that can perform analysis of a substance and information obtainment with relatively high accuracy and reproducibility without previously allowing a carrier to carry a reagent for a color reaction. In the analysis method and the analysis apparatus, the information on an analyte is obtained by using an electromagnetic wave of a frequency including a frequency band which is at least a part of a frequency range of 30 GHz or more and 30 THz or less. A non-fibrous, isotropic porous material is allowed to hold the analyte, the analyte held by the porous material is irradiated with the electromagnetic wave, a change in the propagation state of the electromagnetic wave due to transmission through or reflection by the porous material is detected and information on the analyte is obtained based on the result of the detection.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a method of preparing a spectroscopic sample using a membrane filter.

FIG. 2 is a diagram illustrating an optical arrangement for performing material analysis with a terahertz wave.

FIGS. 3A, 3B and 3C are graphical representations showing the transmittances of membrane filters made of various kinds of materials with respect to a terahertz wave and an in-plane distribution of the transmittance.

FIG. 4 is a graphical representation showing a time waveform of a terahertz wave.

FIG. 5 is a graphical representation showing complex refractive index.

FIG. 6 is a diagram illustrating an optical arrangement for reflection spectroscopy for performing material analysis with a terahertz wave.

FIG. 7 is a diagram illustrating a configuration in which a membrane filter is provided on a mechanical XY stage.

FIG. 8 is a perspective view illustrating an example in which membrane filters are provided on a member having a plurality of wells.

FIG. 9 is a perspective view illustrating the details of an example of the member of FIG. 8.

FIG. 10 is a diagram illustrating a porous material formed of a particulate structure.

FIG. 11 is a diagram illustrating a porous material formed of a sponge-shaped structure.

FIG. 12 is a diagram illustrating a porous material formed of a fibrous structure.

FIG. 13 is a diagram illustrating a porous material including a fibrous structure.

FIG. 14 is a diagram illustrating a state in which a liquid analyte permeates a membrane filter and is held thereby uniformly.

FIG. 15 is a diagram illustrating a state in which a liquid analyte permeates a membrane filter and is held thereby nonuniformly.

FIG. 16 is a graphical representation illustrating a comparison of amplitude transmittances of denatured molecule and normal molecule of BSA.

FIG. 17 which is composed of FIGS. 17A and 17B are Table 1 showing the transmittances of various kinds of membrane filters with respect to a terahertz wave.

FIG. 18 is a diagram illustrating an example of a membrane filter provided on a rotary disk.

FIGS. 19A, 19B, and 19C are diagram illustrating examples of membrane filters using a total-reflection prism coupler.

FIGS. 20A, 20B, and 20C are graphical representation showing transmittance spectra of compounds containing a nucleic acid base.

FIGS. 21A and 21B are graphical representation showing comparative examples of transmittance spectra of compounds containing a nucleic acid base, which were measured by using a conventional membrane filter.

Claims

1. An analysis method of obtaining information on an analyte by using an electromagnetic wave of a frequency including a frequency band which is at least a part of a frequency range of 30 GHz or more and 30 THz or less, the method comprising: allowing a non-fibrous, isotropic porous material to hold an analyte;irradiating the analyte held by the porous material with an electromagnetic wave; anddetecting a change in propagation state of the electromagnetic wave due to transmission through or reflection by the porous material, and obtaining information about the analyte based on a result of the detection.

2. The analysis method according to claim 1, wherein the porous material comprises at least one selected from the group consisting of polypropylene, polysulfone, nylon, polyethersulfone, Teflon, polyolefin, polyethylene, polystyrene, and ethylene tetrafluoride resins.

3. The analysis method according to claim 1, wherein after the porous material is allowed to hold a solution or lysate of a biomolecule and subjected to drying, the information is obtained.

4. The analysis method according to claim 1, wherein after the porous material is allowed to hold a biomolecule and the information is obtained, the biomolecule is eluted from the porous material for reuse.

5. The analysis method according to claim 1, wherein when detecting the change in the propagation state of the electromagnetic wave due to the reflection by the porous material, a member that totally reflects the electromagnetic wave is used, the porous material is disposed in the vicinity of a reflective surface of the totally reflecting member, and the information on the analyte held by the porous material is obtained.

6. The analysis method according to claim 1, wherein a plurality of the porous materials at least one of which holds the analyte are disposed on a rotary member rotatable about a center in a plane not parallel to the travel direction of the electromagnetic wave, at locations radially apart by the same distance from the center, the porous materials are sequentially brought into a detection position by rotating the rotary member, and the change in the propagation sate of the electromagnetic wave due to transmission through or reflection by the porous materials brought into the detection position is sequentially detected.

7. The analysis method according to claim 1, wherein the porous material has an electromagnetic wave amplitude transmittance of 90% or more at 2.0 THz.

8. The analysis method according to claim 1, wherein when an index indicating constancy of the amplitude transmittance with respect to frequency in the frequency band of the electromagnetic wave is defined as the absolute value of a value obtained by subtracting 1 from the amplitude transmittance TM of a frequency near the middle of a terahertz wave frequency band used in the measurement and dividing the resulting value by a difference between the amplitude transmittance TH at the upper limit of the frequency band and the amplitude transmittance TL at the lower limit of the frequency band, the porous material has the index of 20 or more.

9. An analyte holding member for holding the analyte from which information is obtained by the analysis method set forth in claim 1, comprising a partition wall for holding the analyte in a region and the porous material disposed inside the partition wall and having, in a region other than the region defined by the partition wall, at least a member which does not transmit the electromagnetic wave.

10. An analysis apparatus for performing the analysis method set forth in claim 1, comprising an electromagnetic wave irradiating unit for irradiating the porous material with the electromagnetic wave, and an electromagnetic wave detecting unit for detecting the change in the propagation state of the electromagnetic wave due to the transmission through or the reflection by the porous material.