JP6205299B2 - Sample loading plate - Google Patents

Description

  The present invention relates to a sample loading plate for loading a sample.

  Matrix Assisted Laser Desorption / Ionization (MALDI) is known as one of ionization methods in mass spectrometry. In MALDI, in order to analyze analytes that are difficult to absorb laser light and analytes that are easily damaged by laser light, the analysis target is a substance (matrix) that easily absorbs laser light and is easily ionized. The sample (matrix and analysis object) is ionized by irradiating the sample with a laser beam in which an object is dispersed.

  In a mass spectrometer using MALDI, a sample is generally arranged on a metal plate called a sample plate (or target plate), and laser light is irradiated to the sample arranged on the plate. At this time, a voltage is applied to the metal plate as necessary in order to accelerate ions generated with the irradiation of the laser beam.

  As a prior art described in the publication, a hydrophobic coating such as synthetic wax, natural wax, lipid, organic acid, ester, silicon oil, or silica polymer is applied to the first surface of a rectangular plate made of conductive stainless steel. Is used for MALDI analysis (see Patent Document 1).

  In addition, as a prior art described in another publication, a composite coating including a hydrophobic coating and a coating of a thin film mixture of a matrix and a boundary polymer is formed on at least a part of the first surface of a conductive stainless steel substrate. It is described that the applied sample plate is used for MALDI analysis (see Patent Document 2).

JP 2005-536743 A JP 2007-502980 A

  By the way, when a liquid sample is loaded on a sample plate (sample loading plate), it is important that the sample properly spreads on the sample loading plate and stays stably in the sample loading area. When the wettability of the sample loading plate is inappropriate, for example, in mass spectrometry using MALDI, there is a concern that an error may occur in the analysis result. That is, when the sample wetting and spreading on the sample loading plate is large, the density of the sample in the sample loading region (analysis region) decreases, and the amount of ions generated by laser irradiation decreases. On the other hand, when the spread of the sample is small, the sample does not spread over the entire sample loading area, which causes a problem that the analysis cannot be performed appropriately.

  An object of the present invention is to provide a sample loading plate capable of properly spreading a sample on the sample loading plate.

  The sample loading plate of the present invention is a sample loading plate having a sample loading area for loading a sample on a substrate, and the substrate or the lower layer is directly or via an underlayer on the surface of the substrate. A hydrophobic layer having a higher hydrophobicity than the ground layer is formed, and a groove having a bottom portion where the substrate or the base layer is exposed is formed in the hydrophobic layer from the side on which the sample is loaded to the substrate side. The sample loading area is constituted by an area surrounded by the groove, and the hydrophobic layer at the peripheral edge of the groove is covered with at least a covering layer made of a component constituting the substrate or the base layer. Features. By adopting such a configuration, it is possible to keep the sample properly wet and spread by the bottom of the groove where the substrate and the underlayer, which are more hydrophilic than the hydrophobic layer, and the coating layer are exposed, and to stabilize the sample. It becomes possible to stay.

Furthermore, the coating layer is formed of a molten scattered matter generated when the substrate or the base layer is melted. Further, the groove is formed by laser laser processing, and the molten scattered material is formed by the laser laser processing for forming the groove. With this configuration,
It is possible to facilitate the formation of the coating layer.

  The substrate is insulative, and the base layer is conductive. By adopting such a configuration, the present invention can be applied to an analysis that requires conductivity in a sample loading plate such as MALDI.

  The underlayer may exhibit a color different from that of the substrate due to light interference. Furthermore, the base layer is formed by laminating a metal layer made of a metal material and a transparent layer made of a material transparent in the visible region. Furthermore, the transparent layer is composed of a metal compound. By setting it as such a structure, the visibility at the time of mounting a sample on a sample loading plate can be improved.

  According to the present invention, it is possible to provide a sample loading plate that allows a loaded sample to spread in the analysis area without excess or deficiency.

(A), (b) is the figure which showed the example of whole structure of the sample mounting plate to which embodiment of this invention is applied. It is sectional drawing for demonstrating the layer structure of a sample loading plate. (A), (b) is a figure for demonstrating the structural example of the conductive interference layer in a sample loading plate. (A)-(c) is a figure for demonstrating the structure of one island mark periphery in a sample loading plate. It is a figure which shows the structural example of a MALDI-TOFMS apparatus.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
<Configuration of sample loading plate>
FIG. 1 is a diagram showing an example of the overall configuration of a sample stacking plate 100 to which the present embodiment is applied. Here, FIG. 1A is a top view of the sample loading plate 100 as viewed from the sample loading side, and FIG. 1B is a cross-sectional view taken along the line IB-IB in FIG.

  The sample loading plate 100 according to the present embodiment is a MALDI-TOFMS (Matrix Assisted Laser Desorption / Ionization-Time of Flight Mass Spectrometry) in a state where a sample 200 (see FIG. 4 to be described later) including an analysis object is loaded. The laser desorption ionization-time-of-flight mass spectrometry apparatus 1 (see FIG. 5 described later) is mounted and used.

  The sample stacking plate 100 is laminated so as to cover the surface of the substrate 110 having a front surface and a back surface, and a plurality of grooves 130 are formed in a part thereof. The laminated film 120 is provided.

  Here, as shown in FIG. 1A, the substrate 110 constituting the sample loading plate 100 has a shape in which two corners positioned below in a horizontally long rectangle are punched into a rectangular shape. . From another point of view, it can be said that the substrate 110 has a shape in which two horizontally long rectangles are arranged vertically. In the sample stacking plate 100, the laminated film 120 covers the surface of the substrate 110 excluding the site where the groove 130 is formed. In this example, the laminated film 120 or the like is not provided on the back surface of the substrate 110, and the entire back surface of the substrate 110 is exposed to the outside.

  Further, as shown in FIG. 1B, the surface of the substrate 110 is exposed to the outside in the portion of the sample stacking plate 100 where the groove 130 is formed with respect to the laminated film 120. In this example, the width of the groove 130 is several tens μm to several hundreds μm.

In the sample stacking plate 100 of the present embodiment, various markings shown in FIG. 1A are provided on the surface side of the substrate 110 by a plurality of grooves 130 formed in the laminated film 120.
More specifically, first, island marks 131 each having a C-shape are formed on the surface side and the central portion of the sample stacking plate 100 by a plurality of groove portions 130, each having 6 rows × 8 columns ( 48 in total). In the sample stacking plate 100 of the present embodiment, the diameter of each island mark 131 is 2 mm, and the interval between two island marks 131 adjacent vertically or horizontally is also 2 mm.

  In addition, on the surface side of the sample loading plate 100, a row address mark 132 indicating a row position of each island mark 131 is formed by a plurality of grooves 130 on the left side of the plurality of island marks 131 arranged in 6 rows × 8 columns. Is formed. In this example, alphabets “A” to “F” are assigned as row addresses to the first to sixth rows, respectively.

  Further, on the surface side of the sample loading plate 100, a column address mark 133 indicating a column position of each island mark 131 is formed by a plurality of groove portions 130 above the plurality of island marks 131 arranged in 6 rows × 8 columns. Is formed. In this example, Arabic numerals “1” to “8” are assigned as column addresses to the first to eighth columns, respectively.

  Further, on the surface side of the sample stacking plate 100, on the lower left side of the plurality of island marks 131 arranged in 6 rows × 8 columns, a serial number 134 (provided to the sample stacking plate 100 by a plurality of grooves 130). In this example, “000535”) is formed. Furthermore, on the surface side of the sample stacking plate 100, on the lower right side of the plurality of island marks 131 arranged in 6 rows × 8 columns, a bar including a code assigned to the sample stacking plate 100 by the plurality of grooves 130 is provided. A cord 135 is formed.

  Furthermore, among the plurality of island marks 131 arranged in 6 rows × 8 columns on the surface side of the sample stacking plate 100, a plurality of groove portions 130 are provided in the vicinity of the four corners and at the five central portions. Each has a cross shape, and an alignment mark 136 is formed as a mark for positioning the sample stacking plate 100 in the MALDI-TOFMS apparatus 1 (see FIG. 5) described later.

FIG. 2 is a sectional view for explaining the layer structure of the sample stacking plate 100 shown in FIG.
As described above, the sample stacking plate 100 according to the present embodiment is laminated so as to cover the surface of the substrate 110 and the substrate 110, and a plurality of grooves 130 (one groove in FIG. And a laminated film 120 on which only 130 is formed).

  Here, the board | substrate 110 is comprised with the ceramic material which has insulation. In the present embodiment, the substrate 110 is made of alumina ceramic having a purity of about 96%, the thickness is 800 μm, and the flatness of the front and back surfaces is 5 μm or less. However, in this example, since the substrate 110 is made of a ceramic material, minute irregularities due to the presence of ceramic (alumina) grains and grain boundaries are present on the front and back surfaces of the substrate 110. . The substrate 110 exhibits a white color when irradiated with white light such as sunlight.

  Further, the laminated film 120 as an example of the stacking layer has conductivity and is configured to exhibit a predetermined color by light interference when irradiated with white light, and is a conductive interference layer (layered on the substrate 110). A base layer) 121, and a hydrophobic layer 122 that has higher hydrophobicity than the substrate 110 and is stacked on the conductive interference layer 121, and on which a sample 200 (see FIG. 4 described later) is loaded. Yes.

  The conductive interference layer 121 of the present embodiment is made of a metal material having conductivity, and is made of a first metal layer 1211 stacked on the substrate 110 and an inorganic material transparent in the visible region. And a first transparent layer 1212 laminated on the first metal layer 1211; a second metal layer 1213 made of a conductive metal material and laminated on the first transparent layer 1212; and a visible region And a second transparent layer 1214 that is laminated on the second metal layer 1213 and that is to be laminated with the hydrophobic layer 122.

  Here, each structure of the 1st metal layer 1211, the 1st transparent layer 1212, the 2nd metal layer 1213, and the 2nd transparent layer 1214 which comprises the conductive interference layer 121 depends on the electroconductivity requested | required and the color which should be exhibited. The design can be changed as appropriate. However, the color to be exhibited by the conductive interference layer 121 is preferably a chromatic color (red, orange, yellow, green, blue, indigo, purple, etc.) excluding achromatic colors such as white, gray, and black.

  In the present embodiment, the first metal layer 1211 and the second metal layer 1213 have a function as a metal layer, and the first transparent layer 1212 and the second transparent layer 1214 are a metal compound layer or a transparent layer. As a function.

  Further, the hydrophobic layer 122 of the present embodiment is made of a hydrophobic material containing Si (silicon), C (carbon), and F (fluorine). The water contact angle of the hydrophobic material constituting the hydrophobic layer 122 is 110 °, and the thickness of the hydrophobic layer 122 is about 1 nm to 2 nm. In this embodiment, each layer of the substrate 110 and the conductive interference layer 120 described above is made of a material having higher hydrophilicity than the hydrophobic layer 122 (in this example, alumina).

  Furthermore, the sample loading plate 100 of this embodiment has a coating layer 140 made of components constituting the substrate 110 and the conductive interference layer 121 on the hydrophobic layer 122 at the peripheral edge of the groove 130. Since the covering layer 140 is made of components constituting the substrate 110 and the conductive interference layer 121, the covering layer 140 is more hydrophilic than the hydrophobic layer 122 and exhibits conductivity. The covering layer 140 is formed with a thickness that is transparent in the visible region, and is configured not to impair the color of the conductive interference layer.

  Next, a configuration example of the conductive interference layer 121 will be described. FIG. 3 is a diagram for explaining a configuration example of the conductive interference layer 121. 3A is a first configuration example in which a conductive interference layer 121 exhibiting a dark blue color is obtained, and FIG. 3B is a second configuration example in which a conductive interference layer 121 exhibiting a blue color is obtained. Each is shown.

In the first configuration example shown in FIG. 3A, the first metal layer 1211 is made of Ni (nickel) and its thickness is set to 39 nm. The first transparent layer 1212 is made of Al ₂ O ₃ (alumina) and the thickness thereof is set to 64 nm. Further, the second metal layer 1213 is made of Ti (titanium) and the thickness thereof is set to 8 nm. Furthermore, the second transparent layer 1214 is made of SiO ₂ (silica) and its thickness is set to 68 nm.

On the other hand, in the second configuration example shown in FIG. 3B, the first metal layer 1211 is made of Al (aluminum) and its thickness is set to 250 nm. The first transparent layer 1212 is made of TiO ₂ (titania) and the thickness thereof is set to 66 nm. Further, the second metal layer 1213 is made of Ni (nickel) and the thickness thereof is set to 9 nm. Furthermore, the second transparent layer 1214 is made of SiO ₂ (silica), and its thickness is set to 135 nm.

  In the present embodiment, as the conductive interference layer 121, a metal layer (more specifically, the first metal layer 1211 and the second metal layer 1213) and a transparent layer (more specifically, the first transparent layer 1212 and the second transparent layer). By adopting the laminated structure of the layer 1214), a specific wavelength of light (white light) incident from the outside is reflected by optical interference. Here, the degree of optical interference (which wavelength of light is reflected) is determined by the mutual relationship between the constituent material (refractive index) and thickness of each layer constituting the conductive interference layer 121. Thereby, the conductive interference layer 121 adopting the first configuration example shown in FIG. 3A exhibits a dark blue color, and the conductive interference layer 121 adopting the second configuration example shown in FIG. It will be blue. Therefore, it is possible to obtain the conductive interference layer 121 exhibiting a desired color (chromatic color) by appropriately changing the laminated structure (constituent material (refractive index) and thickness) of the conductive interference layer 121.

  Further, in the present embodiment, the sample stacking plate 100 is configured by stacking the laminated film 120 exhibiting a chromatic color (for example, the dark blue color or the blue color described above) on the substrate 110 composed of white alumina ceramics. Thus, the substrate 110 is exposed at a portion where the groove 130 is formed in the laminated film 120. For this reason, the island mark 131, the row address mark 132, the column address mark 133, the serial number 134, the bar code 135, and the alignment mark 136 (all refer to FIG. 1) formed on the sample stacking plate 100 by each groove 130 are white. As a result, the visibility of each of these markings is enhanced by the contrast with the laminated film 120 exhibiting a chromatic color.

Here, in both the first configuration example shown in FIG. 3A and the second configuration example shown in FIG. 3B, the second transparent layer 1214 that is the uppermost layer of the conductive interference layer 121 is made of SiO ₂ ( The reason why it is composed of (silica) is as follows.
In the sample loading plate 100 of the present embodiment, the hydrophobic layer 122 is formed on the second transparent layer 1214 constituting the conductive interference layer 120 as shown in FIG. In the sample loading plate 100, in order to suppress the peeling of the hydrophobic layer 122 from the conductive interference layer 121, it is necessary to improve the adhesion between the conductive interference layer 121 and the hydrophobic layer 122.

In this embodiment, a hydrophobic material containing Si (silicon) is used as the hydrophobic layer 122 as described above. Therefore, in the present embodiment, by using the same SiO ₂ (silica) containing Si (silicon) as the hydrophobic layer 122 as the second transparent layer 1214 to be laminated with the hydrophobic layer 122 in the conductive interference layer 121. The adhesion between the conductive interference layer 121 and the hydrophobic layer 122 is enhanced, and the peeling of the hydrophobic layer 122 from the sample stacking plate 100 is suppressed.

  In the example shown in FIGS. 3A and 3B, the first metal layer 1211 and the second metal layer 1213 constituting the conductive interference layer 121 are made of different metal materials. It is not limited and may be made of the same metal material. In the example shown in FIGS. 3A and 3B, the first metal layer 1211 and the second metal layer 1213 constituting the conductive interference layer 121 are each made of a single metal (pure metal). However, the present invention is not limited to this, and either one or both may be made of an alloy.

  Furthermore, in the example shown in FIGS. 3A and 3B, the first transparent layer 1212 and the second transparent layer 1214 constituting the conductive interference layer 121 are made of different inorganic materials. It is not limited, and it may be composed of the same inorganic material. Furthermore, in the example shown in FIGS. 3A and 3B, the first transparent layer 1212 and the second transparent layer 1214 constituting the conductive interference layer 121 are each made of metal oxide. However, the present invention is not limited to this, and either one or both may be made of an inorganic material such as metal nitride or metal fluoride. In the example shown in FIGS. 3A and 3B, the first transparent layer 1212 and the second transparent layer 1214 constituting the conductive interference layer 121 are made of an insulating material. However, one or both of them may be made of a conductive inorganic material such as ITO (indium titanium oxide).

FIG. 4 is a diagram for explaining the configuration around one island mark 131 in the sample stacking plate 100 shown in FIG. Here, FIG. 4A is a top view of the sample loading plate 100 as viewed from the sample loading side, and FIG. 4B is a sectional view taken along the line IVB-IVB in FIG. ) Is a sectional view taken along the line IVC-IVC in FIG.
FIG. 4 also shows the sample 200 loaded on the sample loading plate 100.

  In the sample stacking plate 100 of the present embodiment, the laminated film 120 is positioned outside the island mark 131 and the island-like portion 120a located inside the island mark 131 obtained by the groove 130 formed in a C shape. By doing so, it has the surrounding part 120b which surrounds the island-like part 120a. In addition, a coating layer 140 is provided on the peripheral edge of the groove 130. However, since the island mark 131 is formed in a C shape with respect to the laminated film 120, the island-shaped portion 120a and the surrounding portion 120b are not completely separated, but are partially integrated. Maintained (connected) state. In this example, since 48 island marks 131 are formed on one sample loading plate 100 (see FIG. 1), there are also 48 island portions 120a. On the sample loading plate 100, the sample 200 can be loaded on each of 48 island portions 120a as an example of a loading area.

<Sample>
Here, the sample 200 loaded on the sample loading plate 100 of the present embodiment will be described.
In MALDI (Matrix Assisted Laser Desorption / Ionization) adopted by the MALDI-TOFMS apparatus 1 (see FIG. 5) described later, a matrix that specifically absorbs a laser that oscillates at a specific wavelength (for example, ultraviolet). A sample 200 in which the analysis object is dispersed and solidified is used as the sample 200. Here, examples of the analysis target include specimens such as blood, saliva, sputum or urine extracted from a living body, various organic compounds, and the like.

  In MALDI, the matrix used in the case of using an ultraviolet laser includes SA (sinapinic acid), CHCA (α-cyano-4-hydroxycinnamic acid), DHBA (2,5-dihydroxybenzoic acid), HABA (2- (4-hydroxy phenylazo) benzoic acid) and the like.

  Here, the sample 200 has been described as including the analysis object and the matrix, but an ionization aid can be further added to the sample 200 as necessary.

<Method of loading sample on sample loading plate>
Next, a method for loading the sample 200 on the sample loading plate 100 will be described.
Here, first, the liquid sample 200 is prepared by mixing the solvent, the matrix, and the analysis object and dispersing the analysis object in the matrix. In the production of the liquid sample 200, the matrix is excessively supplied to the analysis object. Here, since the matrix exhibits white, the obtained sample 200 also exhibits white.

  In the present embodiment, 48 island-shaped portions 120a are provided on one sample loading plate 100, and the sample 200 can be loaded on each island-shaped portion 120a. Therefore, 48 types of samples 200 having different analysis objects can be loaded on one sample loading plate 100 at the maximum.

  Next, the sample stacking plate 100 is installed so that the laminated film 120 faces upward. Then, a liquid sample 200 is supplied to each island 120a in the sample stacking plate 100. At this time, the island-shaped portion 120a as the supply destination is easily discriminated by the island mark 131 (groove 130) having a white color provided corresponding to the island-shaped portion 120a having a chromatic color. The liquid sample 200 may be supplied to the island portion 120a by dropping, for example, or may be supplied to the island portion 120a by application, for example.

  The liquid sample 200 supplied to the island-shaped part 120a tends to spread radially along the surface of the island-shaped part 120a due to the influence of gravity. However, since the liquid sample 200 is supplied to the hydrophobic layer 122 located at the uppermost part of the island-shaped portion 120a, the radial spread of the liquid sample 200 is suppressed by the hydrophobic layer 122. The power to work also works. When the force for spreading the liquid sample 200 radially overcomes the force for suppressing the radial spread, the liquid sample 200 spreads from the island portion 120a toward the surrounding portion 120b. It will follow.

  Here, in the present embodiment, island marks 131 formed by the grooves 130 are formed on the outside of the island-shaped portion 120a, that is, on the portion facing the surrounding portion 120b. For this reason, the sample 200 heading from the island-shaped portion 120a to the surrounding portion 120b is moved to the coating layer 140 at the peripheral portion of the groove 130 constituting the island mark 131 and the inside of the groove 130 before reaching the surrounding portion 120b. It enters and reaches the bottom part, that is, the part where the substrate 110 is exposed. At this time, in this embodiment, since the substrate 110 is made of alumina having higher hydrophilicity than the hydrophobic layer 122, the sample 200 that has entered the coating layer 140 or the groove 130 is in a stable state. It stays on the coating layer 140 or in the groove 130. As a result, it is possible to reduce the number of samples 200 moving from the island-shaped portion 120a to the surrounding portion 120b as compared with the case where the groove portion 130 and the covering layer 140 constituting the alignment mark 131 are not provided, and the sample stacking plate 100 is reduced. It is possible to suppress the spread of the sample 200 on the upper side, and in other words, to avoid mixing two adjacent samples 200 on the sample stacking plate 100.

  Here, the only appropriate adjustment of the spread of the sample 200 on the sample loading plate 100 and the stable retention in the sample loading region is to adjust the width of the groove 130 (the exposed portion of the hydrophilic substrate 110). However, in the present invention, the groove 130 and the covering layer 140 are formed so that the adjustment is possible. According to such a configuration, when it is difficult to widen the groove 130, for example, when the width of the groove 130 cannot be widened structurally, especially when the processing time is increased due to the formation of the wide groove 130, etc. It is valid.

Then, after the supply of the required number of samples 200 to the sample loading plate 100 is completed, each sample 200 loaded on each island 120a in the sample loading plate 100 is dried and solidified. Each sample 200 solidified on the sample stacking plate 100 is continuously white.
Thus, the loading (fixing) of each sample 200 on the sample loading plate 100 is completed.

<Method for manufacturing sample loading plate>
Next, a method for manufacturing the sample stacking plate 100 shown in FIG.

(Substrate formation process)
First, the substrate 110 is formed. More specifically, the base material of the substrate 110 previously molded and baked into the shape shown in FIG. 1 is polished on the front surface and the back surface, the thickness is set to 800 μm, and the flatness is set to 5 μm or less. A substrate 110 is obtained.

(Laminated film formation process)
Next, the laminated film 120 including the conductive interference layer 121 and the hydrophobic layer 122 is formed on the surface of the substrate 110 obtained by the substrate forming step. In this example, the conductive interference layer 121 including the first metal layer 1211, the first transparent layer 1212, the second metal layer 1213, and the second transparent layer 1214, and the hydrophobic layer 122 can be mounted with a plurality of vapor deposition sources. By using a simple electron beam evaporation apparatus, the layers are sequentially stacked in a batch process.

  Specifically, in the process of forming the conductive interference layer 121 in the coating layer forming step, a metal material corresponding to each layer is used as a deposition source on the surface of the substrate 110 disposed in a chamber (not shown), The first metal layer 1211 and the second metal layer 1213 are subjected to electron beam vapor deposition in a high vacuum, and the first transparent layer 1212 and the second transparent layer 1214 in an oxygen atmosphere, respectively. Get each layer you want.

  In the coating layer forming process, in the process of forming the hydrophobic layer 122, the conductive interference layer 121 (more detailed) is disposed in a chamber (not shown) and already formed on the surface of the substrate 110 by the above process. In the second transparent layer 1214), a steel wool containing a hydrophobic material containing Si (silicon), C (carbon) and F (fluorine) is used as an evaporation source with respect to the exposed surface of the second transparent layer 1214). Beam evaporation is performed. Then, the hydrophobic material evaporated from the steel wool adheres onto the second transparent layer 1214, whereby the intended hydrophobic layer 122 is obtained. In the coating layer forming step, the substrate 110 can be heated as necessary. Thus, the stacked film 120 is formed over the entire surface of the substrate 110.

(Groove / coating layer forming step)
Subsequently, by using the second harmonic (532 nm) of the Nd-YAG laser (oscillation wavelength: 1054 nm) on the laminated film 120 formed on the surface of the substrate 110 by the coating layer forming step, the irradiation position is determined. The groove 130 is formed by sequentially moving the groove 130. At this time, the laser power, the irradiation time, and the like are determined so that the laminated film 120 is removed by the irradiated laser and the groove 130 in which the surface of the substrate 110 is exposed to the outside is formed.

  Then, a plurality of grooves 130 are sequentially formed on the laminated film 120 formed on the surface of the substrate 110 by the above process. As a result, an island mark 131, a row address mark 132, a column address mark 133, a serial number 134, a bar code 135, and an alignment mark 136 are provided in the laminated film 120 laminated on the substrate 110 by a plurality of grooves 130. .

  Further, when the groove 130 is formed, the laminated film 120 and the substrate 110 are melted and scattered by heat and physical impact generated by laser processing, and the molten scattered matter is formed on the hydrophobic layer 122 at the peripheral edge of the groove 130. The covering layer 140 to which is fixed is formed. Since the coating layer 140 includes the components of the substrate 110 and the conductive interference layer 121, it is hydrophilic as well as the conductivity, like the groove 130. The thickness and width of the covering layer 140 are determined by the laser power, irradiation time, and the like. Thus, the sample loading plate 100 shown in FIG. 1 and the like is obtained.

<Configuration of MALDI-TOFMS device>
FIG. 5 is a diagram illustrating a configuration example of the MALDI-TOFMS apparatus 1.
The MALDI-TOFMS apparatus 1 ionizes a sample 200 including an analysis object by MALDI (Matrix Assisted Laser Desorption / Ionization) and converts each ion obtained by ionizing the sample 200 to TOFMS (Time of Flight Mass). This is a mass spectrometer that employs a method in which detection is performed by temporal separation by spectroscopy.

  The MALDI-TOFMS apparatus 1 irradiates a laser beam onto a plate holding unit 10 that holds a sample loading plate 100 on which a sample 200 is loaded, and a sample 200 loaded on the sample loading plate 100 held on the plate holding unit 10. Forming a flight space as a flight path of each ion obtained by ionizing the sample 200, which is desorbed from the sample 200 along with the irradiation of the laser light, thereby performing mass separation of each ion. A mass separation unit 30 is provided, and a detection unit 40 that detects each ion that has reached through the flight space in the mass separation unit 30 in time series.

  Among these, the plate holding unit 10 mounts the sample loading plate 100 via the back surface side of the substrate 110 and is provided with a movable base provided to be movable in the x direction and the y direction perpendicular to the x direction shown in FIG. 11 and a clamp 12 each of which has a hook-like shape and is attached to the movable base 11 and sandwiches and holds the sample stacking plate 100 mounted on the movable base 11. Here, the free end side of each clamp 12 is in contact with the loading surface side of the sample 200 on the sample loading plate 100, that is, the laminated film 120 (see FIG. 1), with the sample loading plate 12 mounted on the movable base 11. It is like that.

  In the present embodiment, the movable base 11 and the clamp 12 constituting the plate holding part 10 are both made of a conductive metal material. A first voltage V <b> 1 is applied to the plate holding unit 10 via a movable base 11 from a power source (not shown). Therefore, the first voltage V <b> 1 applied to the movable base 11 is transmitted to the laminated film 120 provided on the sample stacking plate 100 via the clamp 12. Further, in the present embodiment, the plate holding unit 10 moves in the x direction and the y direction via the movable base 11, whereby the sample 200 existing at the laser irradiation position (measurement target position) from the laser light source 20. Can be changed.

  Next, the laser light source 20 is composed of a nitrogen gas laser (oscillation wavelength: 337 nm), which is a kind of ultraviolet laser that operates by pulse oscillation. Note that the oscillation wavelength of the laser light source 20 can be changed according to the absorption wavelength of the matrix constituting the sample 200. Therefore, depending on the type of matrix constituting the sample 200, another laser different from the nitrogen gas laser may be used.

  Furthermore, the mass separation unit 30 includes a first grid 31 that is disposed to face the plate holding unit 20, a second grid 32 that is disposed to face the first grid 31, a second grid 32, and a detection unit 40. And an end plate 33 disposed to face each other. Here, each of the first grid 31, the second grid 32, and the end plate 33 is configured by attaching a metal grid to a metal frame, and is positioned at a position where a laser from the laser light source 20 is irradiated. When viewed from the existing sample 200, it is arranged on the downstream side in the z direction (direction orthogonal to the x direction and the y direction). The first voltage 31 is applied to the first grid 31 by a power source (not shown). On the other hand, the second grid 32 and the end plate 33 are grounded.

Furthermore, the detection unit 40 faces the end plate 33, and is disposed further downstream in the z direction than the mass analysis unit 30 when viewed from the sample 200 present at the laser irradiation position from the laser light source 20.
Although not particularly illustrated, in the MALDI-TOFMS apparatus 1, the plate holding unit 10 holding the sample loading plate 100, the mass separation unit 30, and the detection unit 40 are usually inside a chamber set to a high vacuum. In the flight space, gas particles and the like do not hinder flight.

<Mass analysis operation by MALDI-TOFMS apparatus>
Now, a mass analysis operation by the MALDI-TOFMS apparatus 1 shown in FIG. 5 will be briefly described.

In a state before starting the mass analysis operation, the sample holding plate 100 on which each sample 200 is loaded is attached to the plate holding unit 10. Then, with the sample stacking plate 100 mounted, the movable base 10 of the plate holder 10 is moved in the x direction and the y direction, thereby placing the sample 200 to be analyzed at the measurement target position.
Further, in the state before starting the mass analysis operation, the first voltage V1 applied to the plate holding unit 10 and the second voltage V2 applied to the first grid 31 in the mass separation unit 30 have the same magnitude. Set to (≠ 0).

  Then, with the start of the mass spectrometry operation, laser light is irradiated from the laser light source 20 toward the sample 200 existing at the measurement target position. Then, in the sample 200 irradiated with the laser light, as the matrix in the sample 200 absorbs the laser light, both the matrix constituting the sample 200 and the analysis object are ionized and start to fly in the z direction. .

  At this time, as described above, the same voltage (first voltage V1 = first voltage) is applied to the plate holder 10 that holds the sample stacking plate 100 and the first grid 31 that is disposed to face the plate holder 10. 2 voltage V2) is supplied. The first voltage V <b> 1 applied to the movable base 11 of the plate holder 10 is also supplied to the laminated film 120 provided on the sample stacking plate 100 via the clamp 12. Here, since the first metal layer 1211 and the second metal layer 1213 (see FIG. 2) having conductivity are provided in the stacked film 120, the potential of the stacked film 120 and the stacked film 120 are opposed to each other. The potential difference from the first grid 31 is almost zero. As a result, each ion flying in the z direction from the sample loading plate 100 side provided with the laminated film 120 to the first grid 31 side moves without being accelerated by a potential difference.

  Next, a difference is made between the first voltage V <b> 1 supplied to the plate holding unit 10 and the second voltage V <b> 2 supplied to the first grid 31. When the flying ions are positively charged, the first voltage V1> the second voltage V2, and when the flying ions are negatively charged, the first voltage V1 <second. The voltage is V2. Then, the ions flying along the z direction between the plate holding unit 10 (laminated film 120) and the first grid 31 are accelerated by the potential difference therebetween, and the second grid 32 and the end plate 33 are further accelerated. To reach the detection unit 40.

  At this time, for example, ions having a small molecular weight and light weight reach the detection unit 40 in a shorter flight time. For example, ions having a large molecular weight and heavy weight reach the detection unit 40 in a longer flight time. Become. That is, the time to reach the detection unit 40 varies depending on the weight of the flying ions (molecular weight). And the detection result by the detection part 40 is output to the analysis apparatus (for example, computer apparatus) which is not shown in figure, Mass analysis regarding the analysis target object which comprises the sample 200 is performed by this analysis apparatus.

  In the present embodiment, since an insulating ceramic material is used as the substrate 110 constituting the sample loading plate 100, the sample 200 loaded on the sample loading plate 100 from the plate holding unit 10 via the substrate 110 is used. It is difficult to apply a voltage. Therefore, in this embodiment, the stacked film 120 (more specifically, the conductive interference layer 121) that is formed on the substrate 110 and on which the sample 200 is loaded is made conductive, so that the sample 200 is electrically conductive. The voltage can be applied. Further, in this embodiment mode, the coating layer 140 formed over the stacked film 120 is also provided with conductivity so that voltage application to the sample is assisted.

  In the present embodiment, the sample 200 is loaded on the island-shaped portion 120 a that is inside the island mark 131 in the laminated film 120 provided on the sample loading plate 100. However, as described above, since the island-shaped portion 120a and the surrounding portion 120a are integrated by making the island mark 131 C-shaped, the first voltage is also applied to the island-shaped portion 120a on which the sample 200 is loaded. V1 is applied.

  Here, in the sample loading plate 100, the first metal layer 1211 and the second metal layer 1213 constituting the conductive layer are not exposed on the surface, but the sample loading plate 100 is mounted on the movable substrate 11 using the clamp 12. It is considered that the clamp 12 and the second metal layer 1213 and / or the first metal layer 1211 are in direct contact with each other due to scratches or the like formed at the time of attachment, and conduction is established between them.

  In the present embodiment, the conductive interference layer 121 of the laminated film 120 provided on the sample stacking plate 100 is provided with a chromatic color function and a conductive function. Compared with the case where it provides in, it becomes possible to simplify the structure of the sample loading plate 100. FIG.

  Further, in the present embodiment, a plate made of ceramics instead of a metal plate is used as the substrate in the sample loading plate 100. Thereby, the sample loading plate 100 of the present embodiment is less likely to be deformed due to bending force or twisting force. Therefore, the sample loading plate 100 according to the present embodiment can maintain the flatness of the stacked film 120 formed on the substrate 110 for a long period of time. Further, deformation of the sample stacking plate 100 when the sample stacking plate 100 of the present embodiment is mounted on the holding plate 10 is also suppressed.

In this embodiment, alumina ceramics is used as the substrate 110, but the present invention is not limited to this.
In this embodiment, each layer constituting the laminated film 120 is formed by using the electron beam evaporation method, but the present invention is not limited to this, and other film forming methods may be used. It doesn't matter.
In this embodiment, the structure is such that the surface of the substrate 110 is exposed at the bottom of the groove 130. However, any of the layers constituting the laminated film 120 may be exposed as the bottom of the groove 130. .
Furthermore, in the present embodiment, the groove 130 is formed in the sample stacking plate 100 using the laser processing method, but the present invention is not limited to this, and the formation using another method may be performed. Absent.
In this embodiment, the sample loading plate 100 has been described as a sample plate used for MALDI. However, the present invention is not limited to this, and can be widely used as a plate for loading a liquid sample.

DESCRIPTION OF SYMBOLS 1 ... MALDI-TOFMS apparatus, 10 ... Plate holding part, 20 ... Laser light source, 30 ... Mass separation part, 40 ... Detection part, 100 ... Sample loading plate, 110 ... Substrate, 120 ... Laminated film 120a ... Island-like part, 120b DESCRIPTION OF SYMBOLS Enclosing part 121 ... Conductive interference layer 122 ... Hydrophobic layer 130 ... Groove 131 ... Island mark 132 ... Row address mark 133 ... Column address mark 134 ... Serial number 135 ... Bar code 136 ... Alignment mark , 140 ... coating layer, 200 ... sample, 1211 ... first metal layer, 1212 ... first transparent layer, 1213 ... second metal layer, 1214 ... second transparent layer

Claims (7)

A sample loading plate having a sample loading area for loading a sample on a substrate,
A hydrophobic layer having higher hydrophobicity than the substrate or the base layer is formed on the surface of the substrate directly or through the base layer,
In the hydrophobic layer, a groove having a bottom portion where the substrate or the base layer is exposed is formed from the side on which the sample is loaded to the substrate side.
The sample loading area is constituted by an area surrounded by the groove,
The sample loading plate according to claim 1, wherein the hydrophobic layer at the peripheral edge of the groove is covered with a coating layer made of at least the component constituting the substrate or the base layer.   The sample loading plate according to claim 1, wherein the coating layer is constituted by a molten scattered matter generated when the substrate or the underlayer is melted.   3. The sample loading plate according to claim 2, wherein the groove is formed by laser processing, and the molten scattered material is formed by the laser processing for forming the groove.   The sample loading plate according to any one of claims 1 to 3, wherein the substrate is insulative and the underlayer has conductivity.   The sample loading plate according to any one of claims 1 to 4, wherein the underlayer exhibits a color different from that of the substrate due to light interference.   6. The sample stacking plate according to claim 5, wherein the underlayer is formed by laminating a metal layer made of a metal material and a transparent layer made of a material transparent in the visible region.   The sample loading plate according to claim 6, wherein the transparent layer is made of a metal compound.

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