WO2010095677A1

WO2010095677A1 - Target plate and method for producing the same

Info

Publication number: WO2010095677A1
Application number: PCT/JP2010/052424
Authority: WO
Inventors: 渉服部
Original assignee: 日本電気株式会社
Priority date: 2009-02-18
Filing date: 2010-02-18
Publication date: 2010-08-26

Abstract

Disclosed is a target plate comprised of a holder (102) which holds a sample substrate (111) on which a sample is placed, and a closure (101) which has an opening (108) corresponding to a measurement target area (181) of the sample substrate (111). At least the surfaces of the closure (101) and the holder (102) are electrically conductive, and the opening (108) has a contact portion (109) which abuts with the sample substrate (111).

Description

Target plate and manufacturing method thereof

The present invention relates to a target plate used for a matrix-assisted laser desorption / ionization mass spectrometer (MALDI-MS) for fixing a sample mounting substrate and a manufacturing method thereof.

There is an analysis technique using a matrix-assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS) (Reference 1: Japanese Patent Laid-Open No. 2002-042723, Reference 2: Japanese Patent Laid-Open No. 2004-362882, Reference) 3: Refer to Japanese translations of PCT publication No. 2005-513465. In this mass spectrometry, if the sample is charged due to the principle of operation, the ion acceleration state changes and the flight speed of the ions changes. Due to this change, the time required to reach the ion detector changes, and the measured mass deviates from an accurate value. For this reason, in MALDI-TOF-MS, a conductive substrate is generally used as a substrate on which a sample is placed.

However, in recent years, a mass spectrometry imaging technique called imaging MS has been proposed, and the development of this technique has been actively conducted. In this imaging MS, for example, a tissue section is irradiated with a laser, and mass spectrometry is performed for each irradiation position. Further, the sample separated in the flow path provided on the chip is irradiated with a laser according to the separated position, and mass spectrometry is performed for each irradiation position.

A sample such as a biological tissue used in such an analysis has a thickness, and it is not easy to obtain the conductivity of the sample even if it is placed on a conductive substrate. In addition, a sample to be analyzed may be placed on an insulating substrate such as placed on a slide glass or fixed with paraffin or the like. In addition, separation techniques such as capillary electrophoresis and electrophoresis chromatography are often used for the chip, and the chip is often an insulator. Therefore, it is important to perform mass spectrometry imaging using MALDI-TOF-MS on an insulating substrate.

However, when a sample placed on such an insulating substrate is analyzed by MALDI-TOF-MS in which ions are extracted and accelerated by applying a voltage, charging of the sample inherently occurring on the insulating substrate is caused. You must be careful. In MALDI-TOF-MS, as described above, when the sample is charged, the measured mass deviates from an accurate value.

In order to suppress the charging phenomenon of such a sample, there is a method in which a matrix solution mixed with conductive fillers such as carbon and metal particles is used and applied to the sample. According to this method, the filler contained in the applied matrix can be made conductive, and can be electrically connected to the target plate on which the slide glass or the chip is placed, thereby preventing charging. However, this method has a problem that the metal filler reflects the laser and suppresses ionization of the sample. Further, in the case of carbon, there is a problem that the laser absorbs a laser and generates heat, partially decomposes the sample and lowers the detection sensitivity of the sample.

Also, an ionic liquid having conductivity may be used as a matrix. However, in this case, since the liquid matrix is in a liquid state even at room temperature, the position and amount on the sample surface are not stable, such as flowing on the sample surface. Further, coupled with fluidity, for example, the pattern of the sample separated on the chip may be disturbed. For this reason, when using an ionic liquid as a matrix, there existed a problem of reducing position resolution.

As another method for suppressing the charging phenomenon of the sample, there is a method of forming a thin conductive film such as a metal on the sample and conducting with the target plate through this conductive film to prevent charging. In this method, if the thickness of the conductive film is approximately 100 nm or less, the laser transmits to some extent, so that mass spectrometry can be performed. However, when the laser passes through the conductive film, the laser intensity decreases. As a result, there is a problem that the number of samples to be ionized decreases and the detection sensitivity decreases.

Furthermore, as a method for solving this problem, a method called atmospheric pressure MALDI-TOF-MS has been devised. In this method, a sample is first placed in the atmosphere, and a sample ionized by laser irradiation is sucked into the vacuum together with the atmosphere. After that, acceleration is performed by applying a voltage, and the time of flight is measured for mass analysis. In this case, since a voltage is not directly applied to the insulator substrate, charging of the sample can be prevented.

Also, since the sample is installed in the atmosphere, even if the sample is charged, the sample is neutralized by a large number of ions present in the atmosphere. However, in the method using the atmospheric pressure MALDI-TOF-MS, the sample is easily oxidized and deteriorated because the sample is in the atmosphere. In addition, since the flight path of the ionized sample is complicated, there are many sample losses and the sensitivity is poor. Furthermore, since the number of manufacturers that manufacture atmospheric pressure MALDI-TOF-MS is limited, there is a problem that the diffusion rate of the apparatus is extremely low.

As described above, when a sample placed on an insulating substrate is subjected to mass spectrometry imaging by MALDI-TOF-MS, there is a problem that the sample is charged and an accurate mass cannot be measured. In addition, in order to suppress the charging of the sample, it has been proposed to make the matrix applied to the sample conductive, and to use atmospheric pressure MALDI-TOF-MS. There's a problem.

The present invention has been made to solve the above-described problems, and it is an object of the present invention to enable accurate mass spectrometry even when an insulating substrate is used in MALDI-MS analysis.

A target plate according to the present invention is a target plate used in a matrix-assisted laser desorption / ionization mass spectrometer, a holder for holding a sample substrate on which a sample is placed, and an opening corresponding to a measurement target region of the sample substrate The holder and the lid portion have conductivity at least on the surface, and the opening portion has a contact portion that comes into contact with the sample substrate.

The target plate manufacturing method according to the present invention is a target plate manufacturing method used in a matrix-assisted laser desorption / ionization mass spectrometer, and includes a step of forming a holder for holding a sample substrate on which a sample is placed. And a step of forming a lid, and a step of forming an opening corresponding to the measurement target region of the sample substrate of the lid. The holder and the lid have conductivity at least on the surface, and the opening is And a contact portion that contacts the sample substrate.

As described above, according to the present invention, it is possible to obtain an excellent effect that MALDI-MS analysis enables accurate mass spectrometry even when an insulating substrate is used.

FIG. 1 is a perspective view showing a configuration of a target plate in Embodiment 1 of the present invention. FIG. 2 is a perspective view showing the configuration of the target plate in the second embodiment of the present invention. FIG. 3 is a cross-sectional view showing the configuration of the target plate in the second embodiment of the present invention. FIG. 4 is a cross-sectional view showing the configuration of the target plate in the third embodiment of the present invention. FIG. 5 is a perspective view showing the configuration of the target plate in the fourth embodiment of the present invention. FIG. 6 is a cross-sectional view showing the configuration of the target plate in the fifth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Embodiment 1]
First, the first embodiment of the present invention will be described. FIG. 1 is a perspective view showing a configuration of a target plate in Embodiment 1 of the present invention. This target plate is used in a matrix-assisted laser desorption / ionization mass spectrometer (MALDI-MS), and includes a holder 102 that holds a sample substrate 111 on which a sample is placed, and a measurement target region 181 of the sample substrate 111. And a lid 101 in which an opening 108 corresponding to is formed. Note that MALDI-MS includes time-of-flight (TOF), quadrupole, and Fourier transform ion cyclotron resonance types.

The lid 101 and the holder 102 have conductivity at least on the surface. For example, the lid 101 and the holder 102 are made of a metal material such as an aluminum alloy or SUS403. The lid 101 has a thickness of about 0.3 mm to 0.5 mm. Therefore, when the lid 101 is placed on the holder 102 on which the sample substrate 111 is placed and the contact portion 109 is brought into contact with the sample substrate 111, the distance between the upper surface of the lid 101 and the surface of the sample substrate 111 is The lid 101 has a thickness of about 0.3 to 0.5 mm. The lid 101 and the holder 102 may be made of, for example, plastic, and a metal film may be formed on the surface.

In addition, the target plate in the present embodiment is characterized in that the opening 108 of the lid 101 has at least two linear contact portions 109 that extend to the measurement target region 181 and abut against the sample substrate 111. There is. FIG. 1 shows a case where the opening 108 is formed in a rectangular shape and includes two linear contact portions 109 arranged in parallel, and these contact portions 109 come into contact with the contact portion 191 of the sample substrate 111. Yes. Note that two contact portions 109 adjacent to the opening 108 may be in contact with the sample substrate 111. Further, the contact portions 109 on the four sides constituting the opening 108 may be in contact with the sample substrate 111.

Here, a method for manufacturing the above-described target plate will be described. First, a holder for holding a sample substrate on which a sample is placed is formed. Moreover, a cover part is formed. Further, an opening corresponding to the measurement target region of the sample substrate of the lid is formed. Note that the holder and the lid are formed with conductivity at least on the surface. In addition, two linear contact portions that extend to at least the measurement target region and abut against the sample substrate are formed in the opening.

According to the target plate in the present embodiment configured as described above, when the lid 101 is placed on the holder 102 on which the sample substrate 111 is placed, the two contact portions 109 come into contact with the sample substrate 111. The two contact portions 109 are formed in a straight line and extend to the measurement target region 181. Accordingly, the contact portion 109 comes into contact with the surface of the sample substrate 111 so that a surface (plane) equipotential to the lid portion 101 is formed. In addition, a plane equipotential to the lid 101 is formed over the entire measurement target region 181. As a result, according to the present embodiment, as will be described below, in MALDI-MS, the lines of electric force generated by the applied voltage for extracting and accelerating the ions are generated in the sample region 181 in the sample substrate. Incidently enters the surface of 111.

In MALDI-MS, on an insulating sample substrate, the lines of electric force that should be perpendicularly incident on the sample substrate may be distorted by charging of the sample. On the other hand, in this embodiment, as described above, the surface having the same potential as the lid 101 is provided in contact with the surface of the sample substrate 111. In addition, electric force lines, which are properties of electric lines of force, have the continuity with the surrounding equipotential surfaces even on the sample substrate 111 made of an insulating material because of the property of being arranged in the most spatially separated manner. It tries to arrange it so that it is perpendicularly incident. Due to this property, an equipotential surface is also formed on the surface of the sample substrate 111. The lines of electric force generated by the applied voltage for extracting and accelerating the ions are perpendicularly incident on the surface of the sample substrate 111 if an equipotential surface is formed.

The contact part may be either linear or curved. The straight line can more prevent the sample from being charged.

There may be one or more contact parts. Furthermore, it is more preferable that there are two or more. For example, if there is one circular contact portion, the lines of electric force can be aligned. For example, when there are two linear contact portions and these contact portions are in contact with the sample substrate in a relatively parallel state, the effect of aligning the lines of electric force is enhanced.

The contact portion may be in contact with the sample substrate. Furthermore, it is preferable that the contact portion extends near or in the measurement target region of the sample substrate and is in contact with the sample substrate. The contact portion preferably extends, for example, to a distance within about 1.5 mm from the outer extension of the sample measurement target region.

Thus, since the lines of electric force are incident vertically, according to the present embodiment, it is possible to use a normal matrix material that is dried and becomes a solid. Further, it is not necessary to mix a filler that causes a decrease in sensitivity into the matrix solution and to form a conductive film. Therefore, it is possible to accurately measure the mass of ions generated from the sample without causing problems such as a decrease in position resolution and a decrease in detection sensitivity caused by these matrices.

[Embodiment 2]
Next, a second embodiment of the present invention will be described. FIG. 2 is a perspective view showing the configuration of the target plate in the second embodiment of the present invention. This target plate is used in a matrix-assisted laser desorption / ionization mass spectrometer, and has a holder 202 for holding a sample substrate (not shown) on which a sample is placed, and an opening corresponding to a measurement target region of the sample substrate. And a lid 201 on which a portion 208 is formed. The holder 202 includes a guide 203, a positioning pin 204, a magnet 206, and a housing part 207. The lid 201 includes a through hole 205 and a conductive rubber sheet 209.

In the second embodiment, first, a guide 203 is added to the configuration of the first embodiment described above, and a positioning pin 204 and a through hole 205 are added. In the second embodiment, the lid 201 is fitted in the holder 202 in accordance with the guide 203. In addition, a pair (one set) of positioning pins 204 are fitted into a pair (one set) of through holes 205 provided in the lid portion 201, and the relative position between the lid portion 201 and the holder 202 is determined. The Therefore, according to the second embodiment, it is easy to determine the relative positions of the holder 202, the sample substrate, and the lid 201. In this embodiment, the positioning pin 204 is provided on the holder 202 side and the corresponding through hole 205 is provided on the lid 201 side. However, the present invention is not limited to this. For example, a positioning pin may be provided on the lid 201 and a hole corresponding to the holder 202 may be provided.

In the second embodiment, the magnet 206 is added to the configuration of the first embodiment described above. Moreover, the cover part 201 is comprised from the electroconductive material which has magnetism, such as SUS403, for example. By being made of a material having magnetism, the lid 201 is attracted to a group of magnets 206 embedded in the holder 202 with the same polarity, and the lid 201 can be fixed to the holder 202. Moreover, attachment and detachment become easy by fixing with a magnet.

The magnet 206 embedded in the holder 202 has, for example, the upper side (the lid 201 side) aligned with the S pole. Further, the lid 201 that is attracted to the magnet 206 is used. By doing so, when the target plate is inserted into the MALDI-MS, the magnetic field is uniformly applied to the electromagnetic optical system located on the target plate, and adverse effects on the measurement can be suppressed. Note that the holder 202 is preferably made of a conductive material. Further, in order to make the polarity of the magnet 206 to be embedded uniform, it is desirable to make it from a non-magnetized material such as aluminum.

On the upper surface of the holder 202, an accommodating portion 207 made of a recess into which the sample substrate is fitted is formed. In the present embodiment, two accommodating portions 207 are provided. A sample substrate on which a sample is placed is fitted in the accommodating portion 207, and the lid portion 201 is placed thereon. Thus, by fixing the sample substrate to the target plate in this embodiment, measurement by MALDI-MS can be performed.

Here, the opening portion 208 is provided in the lid portion 201 in accordance with the position of the accommodating portion 207 so that a portion (measurement target region) of the sample to be measured is exposed from the target plate (lid portion 201). As an example, a conductive rubber sheet 209 is provided on each side of the opening 208 formed in a rectangular shape. In the second embodiment, the conductive rubber sheet 209 is used as the contact portion 109 of the first embodiment described above. The conductive rubber sheet 209 is electrically connected to the lid portion 201. The conductive rubber sheet 209 has elasticity with the sample substrate when covered with the lid portion 201 and uniformly contacts along the side of the opening 208, and electrically connects the lid portion 201 and the sample substrate. Connect. Therefore, according to the second embodiment, compared to the first embodiment described above, the lid 201 and the sample substrate can be contacted more uniformly as will be described later.

In this embodiment, the conductive rubber sheet 209 is disposed on all four sides of the opening 208. For example, as shown in the cross-sectional view of FIG. 3, when the chip 210 as the sample substrate is fitted in the accommodating portion 207 and the lid portion 201 is put on, the lid portion 201 is attracted by the magnet 206, and the conductive rubber sheet 209 becomes the chip 201. Pressed against the surface. FIG. 3 shows a cross section taken along line AA 'of FIG.

Thus, when the conductive rubber sheet 209 provided on the four sides of the opening 208 comes into contact with the chip 201, the surface of the insulating chip 201 is affected by the equipotential surface formed by the conductive rubber sheet 209. The lines of electric force arranged in the are arranged so as to form an equipotential surface. As a result, the conductive rubber sheet 209 and the surface of the chip 201 in contact with the conductive rubber sheet 209 are equipotential. As a result, charging of the sample can be prevented.

Therefore, when a MALDI-MS of a type in which ions are extracted and accelerated by voltage application is used for the analysis, there is no need to devise measures for conducting between the target plate and the sample placed on the insulating sample substrate. It will be over. That is, a matrix that becomes solid at normal room temperature can be used without using a liquid matrix that lowers the position resolution. Moreover, it is not necessary to mix a conductive filler that causes a decrease in sensitivity into the matrix. Furthermore, it is not necessary to form a thin conductive film on the sample surface that also causes a decrease in sensitivity.

Further, even when two sample substrates having different thicknesses due to processing tolerances are accommodated in the two accommodating portions 207, within the range that can be compensated by the magnetic force of the magnet 206 and the elasticity of the conductive rubber sheet 209, etc. It is possible to bring the surface of the potential into contact with the surface of each sample substrate.

In this way, when a sample placed on an insulating sample substrate is analyzed by MALDI-MS in which ions are extracted and accelerated by voltage application, charging of the sample on the insulating sample substrate is suppressed. be able to. As a result, it is possible to suppress degradation of performance such as the sample itself, detection sensitivity, and position resolution. Thus, according to this Embodiment, the target plate which mounts a slide glass and a chip | tip which can measure exact mass can be provided.

In the above description, the conductive rubber sheet 209 is used, but the present invention is not limited to this. The portion of the conductive rubber sheet 209 only needs to be made of an elastic body having conductivity. For example, a spring such as a coil spring or a leaf spring made of a conductive material such as metal may be used.

[Embodiment 3]
Next, a third embodiment of the present invention will be described. FIG. 4 is a cross-sectional view showing the configuration of the target plate in the third embodiment of the present invention. This target plate is used in a matrix-assisted laser desorption / ionization mass spectrometer, and has a holder 402 for holding a slide glass 410 on which a sample is placed, and an opening 408 corresponding to a measurement target region of the slide glass 410. And a lid portion 401 formed with the. The holder 402 includes a guide 403, a fitting recess 404, a screw hole 405, and a storage portion 407. The lid portion 401 includes a fitting convex portion 411, a leaf spring portion 412, and a through hole 413.

The lid 401 can be fixed to the holder 402 by fitting the fitting convex portion 411 into the fitting concave portion 404 and screwing the screw 421 passing through the through hole 413 into the screw hole 405. Further, the slide glass 410 is pressed against the housing portion 407 and fixed by the leaf spring portion 412 of the lid portion 401 fixed to the holder 402 in this way. In the third embodiment, the contact portion 109 in the first embodiment is configured by the leaf spring portion 412. Therefore, according to the third embodiment, the lid 201 and the sample substrate can be brought into contact with each other more reliably than in the first embodiment described above. In addition, when the cover part 401 is comprised from a metal plate with a plate thickness of about 300 μm, the leaf spring part 412 can be formed integrally with the cover part 401 by bending or cutting.

[Embodiment 4]
Next, a fourth embodiment of the present invention will be described. FIG. 5 is a perspective view showing the configuration of the target plate in the fourth embodiment of the present invention. This target plate is used in a matrix-assisted laser desorption / ionization mass spectrometer, and has a holder 502 for holding a sample substrate (not shown) on which a sample is placed, and an opening corresponding to a measurement target region of the sample substrate. And two lid portions 501 formed with a portion 508. The holder 502 includes a guide 503, a positioning pin 504, a magnet 506, and two accommodating portions 507. The lid portion 501 includes a through hole 505 and a conductive rubber sheet 509.

Each lid 501 is fitted in the holder 502 in accordance with the guide 503. In addition, a set of positioning pins 504 are fitted into a set of through holes 505 provided in the lid portion 501, and the relative positions of the lid portion 501 and the holder 502 are determined. In the present embodiment, as in the second embodiment described above, a positioning pin 504 is provided on the holder 502 side, and a corresponding through hole 505 is provided on the lid portion 501 side. For example, a positioning pin may be provided on the lid 501 and a hole corresponding to the holder 502 may be provided.

The lid portion 501 may be made of a conductive material having magnetism such as SUS403. By being made of a material having magnetism, the lid portion 501 is attracted to a group of magnets 506 embedded in the holder 502 with the same polarity, and the lid portion 501 can be fixed to the holder 502. Moreover, if it fixes with a magnet, attachment or detachment will become easy.

The magnet 506 embedded in the holder 202 has, for example, the upper side (the lid portion 501 side) aligned with the S pole. Further, a lid 501 that is attracted to the magnet 506 is used. By doing so, when the target plate is inserted into the MALDI-MS, the magnetic field is uniformly applied to the electromagnetic optical system located on the target plate, and adverse effects on the measurement can be suppressed. Note that the holder 502 is preferably made of a conductive material. Furthermore, in order to align the polarity of the magnet 506 to be embedded, it is desirable to make it from a non-magnetized material such as aluminum.

In addition, on the upper surface of the holder 502, an accommodating portion 507 formed of a recess into which the sample substrate is fitted is formed. In the present embodiment, two accommodating portions 507 are provided. Further, in the present embodiment, unlike the above-described second embodiment, a plurality of lid portions 501 are provided in accordance with the number of accommodating portions 507. For example, a sample substrate on which a sample is placed is fitted in each of the two accommodating portions 507, and a lid portion 501 is placed on each sample substrate. According to the third embodiment, even if the two sample substrates have different thicknesses, the lid portions 501 can be covered in accordance with the thicknesses of the respective sample substrates. Thus, by fixing the sample substrate to the target plate in this embodiment, measurement by MALDI-MS can be performed.

Here, an opening 508 is provided in the lid portion 501 in accordance with the position of the accommodating portion 507 so that a portion (measurement target region) of the sample to be measured is exposed from the target plate (lid portion 501). A conductive rubber sheet 509 is provided on the side of the opening 508. The conductive rubber sheet 509 is provided in a state of being electrically connected to the lid portion 501. The conductive rubber sheet 509 has elasticity with the sample substrate when the cover portion 501 is covered, and makes uniform contact along the side of the opening 508, and electrically connects the cover portion 501 and the sample substrate. Connect.

In this embodiment, conductive rubber sheets 509 are provided on two opposite sides of the opening 508. In the present embodiment, conductive rubber sheets 509 are provided on two sides along the wide direction of the holder 502 that is rectangular in plan view. For example, as shown in the cross-sectional view of FIG. 6, a chip 510 as a sample substrate is fitted in the housing portion 507 and a lid portion 501 is put on the housing portion 507. As a result, the lid 501 is attracted by the magnet 506 and the conductive rubber sheet 509 is pressed against the surface of the chip 510. Here, when the depth of the dent is deeper than the thickness of the chip 510, as shown in FIG. 6, a relief is formed in consideration of the protruding region of the conductive rubber sheet 509, and the stepping for positioning the substrate is performed. Can be done. FIG. 6 shows a cross section taken along line BB ′ of FIG.

As described above, when the conductive rubber sheet 509 provided on the four sides of the opening 508 contacts the chip 510, the surface of the insulating chip 510 is affected by the equipotential surface formed by the conductive rubber sheet 509. The lines of electric force arranged in the are arranged so as to form an equipotential surface. As a result, the conductive rubber sheet 509 and the surface of the chip 510 in contact with the conductive rubber sheet 509 are equipotential and are not charged. Further, in this embodiment, since the conductive rubber sheet 509 is provided along the width direction of the holder 502, a measure that tends to be equipotential is taken especially in the direction in which the lines of electric force tend to be distorted. Will be.

In the present embodiment, when a single sample substrate is disposed, a lid without an opening 508 may be used in the accommodating portion 507 where the sample substrate is not disposed. As a result, the recess of the accommodating portion 507 in which the sample substrate is accommodated is closed, and an equipotential surface with higher flatness is formed on the target plate.

As described above, according to the target plate in the present embodiment, at least two sides of the surface of the sample substrate are in contact with at least a length along the side surrounding the region to be measured of the sample on the sample substrate. It has the structure to do. The part in contact is a part of the lid part or a conductor (conductive rubber sheet 509) that is electrically connected to the lid part. With this configuration, as described above, charging of the sample on the insulating sample substrate is suppressed, and deterioration of performance such as the sample itself, detection sensitivity, and position resolution can be suppressed, and an accurate mass can be measured.

Some or all of the above embodiments are also described as in the following supplementary notes, but are not limited to the following.

(Appendix 1)
A target plate used in a matrix-assisted laser desorption / ionization mass spectrometer,
A holder for holding a sample substrate on which the sample is placed;
A lid portion having an opening corresponding to the measurement target region of the sample substrate,
The holder and the lid have conductivity on at least the surface,
The opening is a target plate having a contact portion that comes into contact with the sample substrate.

(Appendix 2)
In the target plate described in Appendix 1,
The opening is a target plate having at least two contact portions that come into contact with the sample substrate.

(Appendix 3)
In the target plate described in Appendix 2,
The target plate in which the at least two contact portions are linear.

(Appendix 4)
In the target plate described in Appendix 3,
The said contact part is a target plate arrange | positioned along the wide direction of the said holder, and opposing.

(Appendix 5)
In the target plate according to any one of appendices 1 to 4,
The opening is a target plate that extends to the measurement target region and contacts the sample substrate.

(Appendix 6)
In the target plate according to any one of appendices 1 to 5,
The said contact part is a target plate comprised from the elastic body which has electroconductivity, and is electrically connected and arrange | positioned at the said cover part.

(Appendix 7)
In the target plate according to any one of appendices 1 to 6,
A plate spring portion for holding the sample substrate on the lid portion;
The contact portion is a target plate disposed on the leaf spring portion.

(Appendix 8)
In the target plate according to any one of appendices 1 to 7,
The said cover part is a target plate provided with the said several opening part.

(Appendix 9)
In the target plate according to any one of appendices 1 to 8,
A target plate provided with a recess-shaped accommodation part for accommodating the sample substrate in the holder.

(Appendix 10)
In the target plate according to appendix 9,
A target plate comprising a plurality of the accommodating portions and a plurality of the lid portions for each accommodating portion.

(Appendix 11)
In the target plate according to appendix 10,
The lid corresponding to the accommodating portion that does not accommodate the sample substrate is a target plate in which the opening is not formed.

(Appendix 12)
In the target plate according to any one of appendices 1 to 11,
A target plate provided with a pin for determining the position of the lid with respect to the holder and a through hole corresponding to the pin in the holder and the lid.

(Appendix 13)
A method for producing a target plate for use in a matrix-assisted laser desorption / ionization mass spectrometer comprising:
Forming a holder for holding a sample substrate on which the sample is placed;
Forming a lid,
Forming an opening corresponding to the measurement target region of the sample substrate of the lid, and
The holder and the lid have conductivity on at least the surface,
The said opening part is a manufacturing method of the target plate which has a contact part contact | abutted to the said sample board | substrate.

(Appendix 14)
In the method for manufacturing a target plate according to attachment 13,
The said opening part is a manufacturing method of the target plate which has at least 2 contact part contact | abutted to the said sample board | substrate.

(Appendix 15)
In the method for manufacturing a target plate according to appendix 14,
The method for manufacturing a target plate, wherein the at least two contact portions are linear.

The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

This application claims priority based on Japanese Patent Application No. 2009-034991 filed on Feb. 18, 2009, the entire disclosure of which is incorporated herein.

As described above, according to the present invention, there is provided a target plate that suppresses charging of a sample when a sample placed on an insulating sample substrate is analyzed by MALDI-MS. According to the target plate of the present invention, it is possible to suppress the deterioration of performance such as the sample itself, detection sensitivity and position resolution, and to measure an accurate mass. A slide glass or a chip can be placed on the target plate.

DESCRIPTION OF SYMBOLS 101 ... Lid part, 102 ... Holder, 108 ... Opening part, 109 ... Contact part, 111 ... Sample substrate, 181 ... Measurement object area | region, 191 ... Contact part.

Claims

A target plate used in a matrix-assisted laser desorption / ionization mass spectrometer,
A holder for holding a sample substrate on which the sample is placed;
A lid portion having an opening corresponding to the measurement target region of the sample substrate,
The holder and the lid have conductivity on at least the surface,
The opening is a target plate having a contact portion that comes into contact with the sample substrate.
The target plate according to claim 1,
The opening is a target plate having at least two contact portions that come into contact with the sample substrate.
The target plate according to claim 2,
The target plate in which the at least two contact portions are linear.
The target plate according to claim 3,
The said contact part is a target plate arrange | positioned along the wide direction of the said holder, and opposing.
The target plate according to claim 1,
The opening is a target plate that extends to the measurement target region and contacts the sample substrate.
The target plate according to claim 1,
The said contact part is a target plate comprised from the elastic body which has electroconductivity, and is electrically connected and arrange | positioned at the said cover part.
The target plate according to claim 1,
A plate spring portion for holding the sample substrate on the lid portion;
The contact portion is a target plate disposed on the leaf spring portion.
A method for producing a target plate for use in a matrix-assisted laser desorption / ionization mass spectrometer comprising:
Forming a holder for holding a sample substrate on which the sample is placed;
Forming a lid,
Forming an opening corresponding to the measurement target region of the sample substrate of the lid, and
The holder and the lid have conductivity on at least the surface,
The said opening part is a manufacturing method of the target plate which has a contact part contact | abutted to the said sample board | substrate.
In the manufacturing method of the target plate of Claim 8,
The said opening part is a manufacturing method of the target plate which has at least 2 contact part contact | abutted to the said sample board | substrate.
In the manufacturing method of the target plate of Claim 9,
The method for manufacturing a target plate, wherein the at least two contact portions are linear.