JP2008003028A - Microchip and use method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To readily and surely perform analysis using a coupling test with respect to the components contained in a sample. <P>SOLUTION: This microchip includes a substrate, a first separating flow channel 101 and a first partition plate 200 provided to the first separating flow channel 101. A liquid sample is introduced into the first separating flow channel 101 extending over the entirely thereof and the components in the liquid sample are separated into first and second regions 171 and 172 demarcated by the first partition plate 200 to be fixed, while a liquid reagent containing a substance which forms a composite along with a predetermined component is introduced into the first and second regions 171 and 172. The first partition plate 200 is provided extending over the entire width of the flow channels and constituted so that it is suppressed that the components separated into the first and second regions 171 and 172 in the first separating flow channel 101 to be fixed, go over the first partition plate 200 from either of the first and second regions 171 or 172 to the another of them to diffuse, when they come into contact with the liquid reagent. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a microchip and a method for using the same.

  Proteins that control various biological functions in vivo are important biological components for normal life activities. In addition to functioning alone, it has been found that proteins often exhibit enzyme functions as a complex by binding to other proteins or small biological molecules. Therefore, analyzing the binding between proteins and other biomolecules is important for understanding life. In addition, by preferentially binding a drug having a three-dimensional structure similar to the original binding partner, a drug of a type that exerts a medicinal effect by interfering with the enzymatic function of the protein is produced.

  In any of the above examples, the result of a many-to-many binding experiment will not be understood, so that a specific protein of interest is separated in a form that can be recognized, and one or more binding candidate substances are reacted with it. Let's search for things to combine.

  In the past, this experiment was performed in a test tube, but in recent years, proteins are spotted separately on a small machine such as a microchip, and binding candidate substances are allowed to act on them. A method has been proposed in which the binding is simply detected at a time as to whether or not it has bound to a spot.

  Examples of such a method include a method using a protein array spotted with proteins (Non-Patent Document 1) and a method using a protein-immobilized surface in a protein chip system sold by Cyphagen (Non-Patent Document 2). is there. In these, a target candidate substance is bound to the protein immobilized on the chip surface, and if there is a substance to be bound, the former is detected by a fluorescence or electrochemical method, and the latter is mass spectrometry. To detect.

  As a matter of course, in these methods, in order to produce a protein array or protein chip, a large amount of protein immobilized on a substrate member is purified after artificial synthesis or extracted from a living body and purified in advance. In this state, a large number of spots must be prepared and then spotted one by one in a discrete manner. Thus, the protein that was difficult to prepare was not subject to the assay.

  On the other hand, a method for performing isoelectric point separation in the flow path using a chip having a micro flow path is proposed. According to this, the amphoteric components in the extraction component described above, that is, proteins and peptides can be separated and arranged according to their isoelectric points.

When isoelectric point separation is performed, the structure does not originally have a lid (Non-patent Document 3), or a seal is used as a lid, etc., so that the isoelectric point separation is combined with the microchip substrate, etc. When a combination structure (Non-Patent Document 4) that can be peeled off after the electric point separation is used, the amphoteric component fixed in a powder form remains in place by natural drying or freeze drying after the isoelectric point separation. At this time, in order to improve the separation state, a long flow path may be prepared. When the separation time is desired to be shortened even at the sacrifice of the separation state, the flow path may be shortened.
Lisa Melton, “Proteomics in multiplex”, Nature, 429, p. 101-107 Yokoyama Kenji, “Current Status of Protein Chip Development”, Bio Venture (Yodosha), 2003, May-June, p. 24-27 W. Hattori et al., “An isoelectric focusing chip with microstructured superhydrophillic open channels for coupling with MALDI-MS detection”, MSB2006-20th International Symposium on Micro-Scale Bioseparations, PJ24 Machiko Fujita and 8 others, “High-throughput and high-resolution two-dimensional mapping of PI and M / Z using microchip and MALDI-TOFMS”, MSB2005-19th International Symposium on Micro-Scale Bioseparations, L19-L6-W

  However, in the above-described conventional protein array and protein chip, the antibody immobilized on the substrate member is purified as a pure protein after being artificially synthesized in large quantities or purified after extraction from a living body. Therefore, only substances that have a well-established preparation method, which are only a small part of the amphoteric components in the body, could be tested.

  However, because certain drugs also bind to proteins that could not be assayed by the methods described above, it can cause serious side effects, or conversely, have unexpectedly good effects. Therefore, there is a need to perform a binding assay for all components in the living body.

  Samples extracted from living organisms, such as blood, contain in vivo proteins necessary for human and other living organisms, and the protein groups present in these samples are all protein groups that are desired to be assayed in binding assays. . With a small number of handheld substances, it is possible to test the partner to which they bind by taking time and effort even with the conventional method, but when the number exceeds 10,000, such as a library of drug candidates, According to the law, it takes too much time to test, and in reality it is difficult to test.

  Therefore, if the components in the extracted sample can be discretely arranged one by one, it becomes a protein array, and a complete binding assay can be easily performed. Actually, even if a plurality of components are mixed in one discrete section, if it can be narrowed down to about 10, for example, it is possible to test only the narrowed portion by the conventional method in detail.

  Therefore, the present invention provides a technique for simply and reliably analyzing a component contained in a sample using a binding assay.

According to the present invention,
A substrate,
A flow path provided in a groove shape on the substrate;
A partition plate provided in the flow path;
Including
The liquid sample is introduced over the entire flow path, and the components in the liquid sample are separated into the first and second regions partitioned by the partition plate based on a predetermined property, and are fixed.
A liquid reagent containing a substance that forms a complex with a predetermined component is introduced into the first and second regions of the flow path,
The partition plate is
Provided over the entire width of the flow path,
When the components separated and immobilized in the first and second regions in the flow path come into contact with the liquid reagent, they pass from one of the first and second regions to the other over the partition plate. A microchip configured to suppress diffusion is provided.

Moreover, according to the present invention,
A method of using the microchip,
Introducing a liquid sample to be subjected to mass spectrometry into the flow path, and separating components in the liquid sample into the first and second regions;
After the step of separating components, immobilizing the separated components in the first and second regions;
After the step of immobilizing a component, a liquid containing a substance that forms a complex with a predetermined component in the flow path in a state where the partition plate is disposed between the first region and the second region. Introducing a reagent to form a complex of the predetermined component and the substance;
A method of using a microchip is provided.

  In the present invention, in the microchip flow channel, the liquid sample is introduced over the entire flow channel, and the components in the liquid sample are separated into at least the first region and the second region in the flow channel. Components are immobilized on the respective areas. Here, the first and second regions are arranged side by side along the extending direction of the flow path. The first and second regions are adjacent regions in the flow path and are partitioned by a partition plate. The first region and the second region may be partitioned by a partition plate at least before the introduction of the liquid reagent, and may be partitioned by a partition plate from the separation / fixation stage, or the stage after immobilization. It may be divided by.

  After immobilization, a liquid reagent is introduced into the flow path, and a complex formation reaction is performed in the flow path. At this time, a partition plate is provided over the entire width of the flow path, and when the component comes into contact with the liquid reagent, it is configured to suppress diffusion from one to the other of the first and second regions beyond the partition plate. Thus, the complex formation reaction can be performed while maintaining the state separated into the first and second regions.

  Therefore, according to the present invention, the liquid sample containing a plurality of components is surely spread over the entire flow path and separated in the flow path, and after separation, when the immobilized component comes into contact with the liquid again, It is possible to suppress the diffusion in the direction in which the flow path extends beyond the partition plate, and to stay within a predetermined region. For this reason, it is possible to perform the binding test while discretely arranging the components in the flow path and maintaining the discrete state.

  In the microchip of the present invention, a reference channel having a shape corresponding to the channel may be provided. By providing a reference channel, for example, a liquid reagent is introduced into the channel to perform a complex formation reaction, and only the same liquid sample is separated and immobilized in the reference channel, and these states are changed. A comparative analysis can be performed. Therefore, the components can be analyzed more reliably by comparing the states before and after the formation of the complex of the components in the liquid sample.

  It should be noted that any combination of these components, or a conversion of the expression of the present invention between a method, an apparatus, and the like is also effective as an aspect of the present invention.

For example, according to the present invention,
A lid disposed on the upper surface of the flow path of the microchip substrate of the present invention described above,
Including a second divider,
A lid is provided that is configured such that when the lid is disposed on the substrate, the second partition plate projects into the interior of the channel over the entire width of the channel of the microchip.

  As described above, according to the present invention, it is possible to simply and reliably perform analysis using a binding test on components contained in a sample.

  Embodiments of the present invention will be described below with reference to the drawings. In all the drawings, common constituent elements are denoted by the same reference numerals, and description thereof is omitted as appropriate.

First, the outline of the analysis procedure using the microchip in the present embodiment will be described.
FIG. 1 is a flowchart showing an analysis procedure in the present embodiment.
As shown in FIG. 1, in this embodiment, the analysis of the components in the sample includes the following steps.
Step 11 (S11): Liquid sample introduction step 13 (S13): Separation step 15 (S15): Immobilization step 17 (S17): Binding reagent introduction / complex formation step 19 (S19): Mass spectrometry

  First, a predetermined liquid sample such as a body fluid is introduced into a microchip channel as a sample to be subjected to mass spectrometry (S11). This channel is a separation channel. The specific structure of the microchip and the flow path will be described later.

  And the component contained in a liquid sample is isolate | separated according to a predetermined property (S13). The predetermined properties used for separation include various components such as isoelectric point and size of components, hydrophilicity / hydrophobicity, etc. In the following, amphoteric components in a liquid sample are separated by isoelectric focusing Will be described as an example. By separation, the components are arranged in the first region and the second region of the flow path.

  Here, as a method for improving the separation state, for example, a method of lengthening the flow path formed in the microchip can be mentioned. More specifically, if the planar shape of the flow path is designed in a zigzag shape, for example, a flow path of the order of 10 m can be formed in a 5 cm square chip. Alternatively, by setting the isoelectric point range to be separated narrowly, it is possible to more discretely separate components in a specific isoelectric point range even if the flow paths have the same length.

  Thereafter, the components separated in the flow path are fixed to the separated regions, that is, the first and second regions (S15). The step of immobilizing the component is, for example, a step of freeze-drying the liquid in the flow path. By drying the liquid sample in situ, the liquid sample is fixed in a separated state for each isoelectric point.

  At this time, a microchip without a lid is used, or a microchip with a lid that is provided with a lid at the time of separation and can be peeled off after separation is used. Then, after the isoelectric point separation is completed, the liquid in the microchip is frozen, and in the case of a microchip having a lid, the lid is peeled off to expose the components in the flow path and freeze-dried or air-dried. Thereby, the amphoteric component powder discretely arranged in the flow path is fixed in a predetermined region. As this method, the method described in Non-Patent Document 3 or 4 can be used.

  Alternatively, the liquid sample can be immobilized in the flow path by freezing after separation.

  As described above, the amphoteric components discretely arranged in the flow path can be regarded as the components of the protein array discretely spotted in the first and second regions. This is a protein array chip.

  However, in the configuration of the conventional microchip, even if such a protein array chip can be manufactured, the separated components are not fixed to the base material by covalent bonds, and thus flow out when brought into contact with another liquid. For this reason, in the conventional microchip, it is difficult to supply a liquid to the components separated in the flow path and react with the other components.

  On the other hand, in the present embodiment, a protein array that is isoelectrically separated on a microchip and in a dry state can be tested for binding with other components without destroying the discrete separation state. Specifically, a partition structure (partition plate) is provided in the flow path of the microchip so as not to interfere with the separation and to be separated and not mixed with adjacent components during the binding reaction. Alternatively, the microchip has a configuration in which a partition plate can be set in the flow path using another additional member after separation.

  In any of these cases, after the step 15 for immobilizing the components, the predetermined components and complexes are placed in the flow channel with the partition plate disposed between the first region and the second region of the flow channel. A liquid reagent containing a substance to be formed is introduced into the flow path, a binding reaction is performed to form a complex of a predetermined component and the substance (S17), and the binding reaction solution is dried again. By providing the partition plate in the flow path, it is possible to suppress the immobilized sample from moving in the extending direction in the flow path beyond the partition plate and diffusing in Step 17 of forming the complex. By suppressing the component separated into the first and second regions from diffusing from one side to the other across the partition plate, the separated spots can be prevented from being mixed.

  As a result, in the separation channel after the binding reaction, the product substance, that is, the complex exists in the region where the component in which the binding reaction has occurred is arranged. On the other hand, in a region where a component that does not cause a binding reaction is arranged, the original substance is present.

  In addition, a reference channel (reference channel) having a shape corresponding to the channel may be provided in the microchip. The reference channel is configured to be able to separate and immobilize components in the liquid sample in the same manner as the channel. In this case, also in the reference channel, after the isoelectric point separation of the amphoteric substance mixture solution is performed using the same liquid sample using the above-described procedure, the inside of the channel is dried. For the reference channel, after step 15, the next step 19 is performed without performing the binding reaction using the liquid reagent in step 17 described above.

  Subsequently, the region where the binding reaction has occurred in the flow path is detected by mass spectrometry (S19). Hereinafter, a case where a MALDI (Matrix Assisted Laser Desorption Ionization) type mass spectrometer is used will be described as an example.

  A matrix, which is an ionization promoting substance, is dropped into each channel after the binding reaction. Then, the microchip is arranged at a predetermined position of the mass spectrometer. Using a microchip directly as a target, scanning is performed by irradiating laser light sequentially from the end of the flow path. And the presence or absence of formation of the complex in a 1st and 2nd area | region is detected based on the 1st mass spectrometry spectrum obtained about the flow path which performed the binding reaction.

  It is also possible to determine in which region of the flow channel the binding reaction has occurred by comparing the spectrum obtained for the flow channel that has undergone the binding reaction with the spectrum obtained for the reference flow channel. Further, from the isoelectric point and mass data of the determined region, it is possible to identify a substance forming a complex from among the components in the liquid sample, or to narrow down substance candidates. For example, by setting the flow path in which the binding reaction has been performed and the reference flow path to have the same shape, mass spectra at opposite positions can be compared. If a mass difference is detected in both spectra, it indicates that the substance of the mass difference has bound.

  As described above, a substance that forms a complex with a specific substance can be detected from the entire liquid sample including a plurality of components. According to this embodiment, the binding reaction between substances can be performed in the flow path on the microchip without breaking the separation pattern after isoelectric point separation. In addition, by performing the presence or absence of the binding reaction in adjacent separation channels of the same shape, the state before the formation of the complex and the state after the formation can be realized in each channel, so these states are measured separately. Then, by comparing the signals, the position where the binding reaction has occurred can be specified.

  Here, the first and second regions are illustrated, but even when the components in the sample are separated into a plurality of regions that are equal to or greater than the third region, liquid can be obtained by arranging a partition plate between the regions. Diffusion of components during reagent introduction can be similarly suppressed.

  As an example for realizing the above method, in the microchip of the following embodiment, each separated component does not move during the binding reaction in the channel and the reference channel on the microchip to be used. The structure can be used as a target of a laser desorption ionization mass spectrometer.

  First, in order to prevent the separated components from moving during the binding reaction, a partition plate is formed in the flow path so that the binding reaction liquid does not enter the adjacent compartment beyond the partition plate. In order to manufacture the partition more firmly, a lid structure manufactured so as to overlap or mesh with the partition on the flow path side can also be used.

  However, when a lid without an upper opening is provided, the laser cannot be directly irradiated to the flow path in MALDI mass spectrometry, and ionized substances are not emitted toward the detector. In view of this, an opening for communicating the outside of the first and second regions to the outside is provided by, for example, making a hole at a position corresponding to the upper part of each section partitioned by each partition plate. By using such a lid, it is possible to perform addition of a matrix through the hole, laser irradiation at the time of MALDI mass spectrometry, and radiation of an ionized substance toward the detector.

  In the following embodiment, the analysis procedure described above will be described more specifically. In all the drawings, common constituent elements are denoted by the same reference numerals, and description thereof is omitted as appropriate.

(First embodiment)
FIG. 2 is a plan view showing the configuration of the microchip of this embodiment.
The microchip 100 shown in FIG. 2 is used as a target plate for mass spectrometry. The size of the microchip 100 may be any size that can be mounted as a target on the mass spectrometer to be used.

  The microchip 100 includes a substrate 103, a channel provided in the substrate 103 in a groove shape (first separation channel 101), and a partition plate provided in the first separation channel 101 (first partition plate 200: 3). The microchip 100 is further provided with a reference channel (second separation channel 102) having a shape corresponding to the first separation channel 101.

  As the material of the substrate 103, for example, a material that is easy to be finely processed, such as quartz, glass, or silicon, is preferably used.

  The first separation channel 101 and the second separation channel 102 are provided in a concave shape on the substrate 103. In FIG. 2, a first separation channel 101 and a second separation channel 102 are provided in parallel to each other. In the present embodiment and the following embodiments, a case where the second separation channel 102 is used as a reference channel will be described as an example, but when a plurality of separation channels are provided on the substrate 103, One of these may be a channel used for the binding reaction, and the other may be a reference channel. Further, three or more separation channels may be provided in the microchip 100.

  The microchip 100 includes an introduction part (a liquid reservoir 150 and a liquid reservoir 151) for introducing a liquid into the first separation channel 101 and an introduction part (a liquid reservoir 152 and a liquid reservoir for introducing a liquid into the second separation channel 102. 153). The liquid reservoir 150 and the liquid reservoir 151 are in communication with the first separation channel 101, and the liquid reservoir 152 and the liquid reservoir 153 are in communication with the second separation channel 102.

  A liquid sample is introduced into the first separation channel 101 and the second separation channel 102 as a whole. The components in the liquid sample are separated into the first region 171 and the second region 172 (FIG. 3) partitioned by the first partition plate 200 based on a predetermined property and fixed. In addition, a liquid reagent containing a substance that forms a complex with a predetermined component is introduced into the first region 171 and the second region 172 of the first separation channel 101.

Here, the liquid sample introduced into the first separation channel 101 and the second separation channel 102 includes a biological component such as a biological sample.
The liquid reagent introduced into the first separation channel 101 is a binding assay reagent.

  Note that the first separation channel 101 and the second separation channel 102 may be entirely separated regions, or part of them may be separated regions. In FIG. 2, the first separation channel 101 and the second separation channel 102 include an isoelectric point separation region where a pH gradient is formed, and the first region 171 and the second region 172 are the isoelectric point separation region. It is provided in the inside.

  The microchip 100 further includes a pair of electrodes (first electrode 160 and second electrode 161, first electrode 162 and second electrode 163) that apply an electric field to the isoelectric point separation region. A first electrode 160 and a second electrode 161 are inserted into the liquid reservoir 150 and the liquid reservoir 151, respectively. The first electrode 160 and the second electrode 161 are electrode pairs for isoelectric point separation. Further, a liquid reservoir 152 and a liquid reservoir 153 are respectively provided in communication with both ends of the second separation channel 102, and a first electrode 162 and a second electrode 163 are inserted into these liquid reservoirs, respectively. . The first electrode 162 and the second electrode 163 are also electrode pairs for isoelectric point separation. A chemically stable material is suitable for the first electrode 160 to the second electrode 163, and these are, for example, rod-shaped platinum electrodes.

  The shapes of the first separation channel 101 and the second separation channel 102 are straight lines in FIG. However, the planar shape of these flow paths is not limited to a linear shape, and may be a shape having a bent portion such as a zigzag shape.

  The first separation channel 101 and the second separation channel 102 have a width of, for example, 50 μm or more and 10 mm or less. Moreover, the depth of these flow paths is set to 0.3 μm or more and 1 mm or less, for example.

  Here, when the liquid reagent spreads in the first separation channel 101 during the binding reaction (S17 in FIG. 1), the arrangement state of the amphoteric components concentrated by forming a band in the separation process is destroyed. As a structure for preventing this phenomenon, a partition plate is provided at least in the first separation channel 101. Also, the second separation channel 102 can have the same configuration as the first separation channel 101. The partition plate only needs to be provided at least in the first separation channel 101 that performs the binding reaction, but from the viewpoint of aligning the sample separation state in the first separation channel 101 and the second separation channel 102, It is preferable to provide a partition plate in both the first separation channel 101 and the second separation channel 102. Further, it is more preferable to provide a partition plate at the same position in each of the first separation channel 101 and the second separation channel 102.

FIG. 3A and FIG. 3B are diagrams showing a configuration example of the first separation channel 101. FIG. 3A is a plan view of the first separation channel 101, and FIG. 3B is a cross-sectional view taken along line AA ′ of FIG.
As shown in FIG. 3A and FIG. 3B, in the present embodiment, the first partition plate 200 is provided on the flow path bottom surface 201. The first partition plate 200 is disposed between the channel bottom surface 201 and the channel top surface 202. Here, the channel bottom surface 201 is in the same plane as the top surface of the microchip 100.

  The first partition plate 200 is provided over the entire width of the first separation channel 101 and the second separation channel 102, and is separated and fixed into the first region 171 and the second region 172 in the channel. It is configured to prevent the components from diffusing beyond the partition plate from one of the first region 171 and the second region 172 to the other when contacting the liquid reagent.

  The first partition plate 200 prevents the components in the liquid sample from being diffused in the direction in which the flow path extends and moving to the second region 172 after the components in the liquid sample are fixed to the first region 171. The first partition plate 200 is a partition wall that suppresses the movement of the component fixed to the first separation channel 101 in the direction in which the channel extends. By providing the first partition plate 200 over the entire width of the flow path, variations in the separation state in the width direction of the flow path are reduced, and after the separation, the diffusion of the immobilized components in the flow path extending direction is effectively performed. Can be blocked.

  Here, as shown to Fig.3 (a), the some 1st partition plate 200 is mutually arrange | positioned along the extension direction of the flow path 101 for 1st separation. The plurality of first partition plates 200 are orthogonal to the extending direction of the flow path. The some 1st partition plate 200 may be provided in the whole flow path.

  In the microchip 100, the side wall (the channel side wall 203) of the first separation channel 101 and the first partition plate 200 are provided continuously. More specifically, the first partition plate 200 and the side wall of the first separation channel 101 are formed continuously and integrally. Such a first partition plate 200 can be produced by a general method such as dry etching using two different masks during microfabrication. Further, the first partition plate 200 can be built in the substrate 103 together with the first separation channel 101 and the second separation channel 102 in the fine processing step of the substrate 103.

  In addition, the microchip 100 is provided in the vicinity of the first separation channel 101 and the first separation channel 101, and the second separation channel 102 provided along the first separation channel 101. The first partition plate 200 is provided in the first separation channel 101 and the second separation channel 102, and the position corresponds to the first partition plate 200 provided in the first separation channel 101. The first partition plate 200 of the second separation channel 102 is provided. Thereby, the separation state of the flow path not used as the flow path into which the binding reagent is introduced can be more reliably aligned.

  The plurality of first partition plates 200 are arranged at regular intervals, for example. The thickness of the first partition plate 200, that is, the length in the extending direction of the flow path can be appropriately set according to the processing method, and is, for example, about 0.1 mm. From the viewpoint of further reducing the influence on separation, it is preferable to reduce the thickness of the first partition plate 200. The length in the flow path extending direction of the region partitioned by the first partition plate 200 is appropriately set according to the analysis purpose. Moreover, the distance between the centers of the 1st partition plate 200 shall be about 50-2000 micrometers, for example. When it is desired to finely separate a plurality of components in the liquid sample for each component, the distance between the centers of the first partition plate 200 is set small to shorten the length of the partitioned region. Further, when it is desired to roughly divide into a group of regions including a plurality of components, the distance between the centers of the first partition plate 200 is set to be large to increase the length of the partitioned region.

  The first partition plate 200 is provided on the bottom surface of the first separation channel 101, and the height h 1 of the first partition plate 200 is lower than the depth H of the first separation channel 101. By doing so, it is possible to prevent the first partition plate 200 from interfering with the separation, so that the separation is further ensured.

  Further, the height h1 of the first partition plate 200 is set according to the depth H of the first separation channel 101. The height h1 of the first partition plate 200 is set to a height that does not hinder the liquid sample introduced into the liquid reservoir 150 or the liquid reservoir 151 from spreading over the first separation channel 101 and being separated.

  Specifically, the depth H of the first separation channel 101 and the height h1 of the first partition plate 200 are set to h1 <(2/3) H, preferably h1 ≦ (1/2) H. By doing so, the liquid sample can be more reliably introduced into the entire first separation channel 101 and the components in the liquid sample can be further reliably separated.

  Further, the lower limit of the height h1 of the first partition plate 200 is that the components separated into the predetermined region in the first separation channel 101 when the liquid reagent is introduced exceed the first partition plate 200 and other components are separated. The height may be any height that does not move to the region, and is set according to, for example, the supply method and supply amount of the binding reagent to the first separation channel 101. For example, (1/10) H ≦ h1, preferably (1/5) H ≦ h1.

Next, a method for using the microchip 100 shown in FIGS. 2 and 3 will be described. The basic procedure of analysis using the microchip 100 is as described above with reference to FIG.
A step of introducing a liquid sample to be subjected to mass spectrometry into the first separation channel 101 and the second separation channel 102 (S11 in FIG. 1) and separating components in the liquid sample (S13 in FIG. 1). ,
After the step of separating the components, the step of fixing the components at the separated position (S15 in FIG. 1) and the step of fixing the components are combined with a predetermined component in the first separation channel 101. Introducing a liquid reagent (binding reagent) containing a substance that forms a body to form a complex of a predetermined component and the substance (S17 in FIG. 1);
After the step of forming the complex, a step of performing laser desorption ionization mass spectrometry of the liquid sample (S19 in FIG. 1) is included.

The step of performing laser desorption ionization mass spectrometry in step 19 includes:
Irradiating the first separation channel 101 with laser light to obtain a first mass spectrometry spectrum, and whether or not the complex is formed in the first region 171 and the second region 172 based on the first mass spectrometry spectrum Detecting step,
including.
More specifically, the step of performing laser desorption ionization mass spectrometry in step 19 includes:
Step 21: irradiating the first separation channel 101 with laser light to obtain a first mass spectrometry spectrum;
Step 23: irradiating the second separation channel 102 with laser light to obtain a second mass spectrometry spectrum;
Step 25: comparing the first mass spectrometry spectrum and the second mass spectrometry spectrum to detect formation of a complex in the first region 171 and the second region 172 of the first separation channel 101;
including.

Hereinafter, the analysis procedure will be described in more detail.
First, a liquid sample is introduced into two separation channels, that is, both the first separation channel 101 and the second separation channel 102. The liquid sample is, for example, a sample extracted from a living body, which is used as an amphoteric component mixture for analysis, and a mixture obtained by mixing an amphoteric carrier with the amphoteric component mixture is used, for example, from the liquid reservoir 150 and the liquid reservoir 152. It introduce | transduces into two flow paths for separation (S11 of FIG. 1). As the amphoteric carrier, known materials such as commercial products can be used. Alternatively, the liquid may be introduced from the liquid reservoir 151 and the liquid reservoir 153 into two separation channels.

  Next, the microchip 100 is placed in a constant humidity box maintained in a humidity state close to 100%, and isoelectric point separation is performed (S13 in FIG. 1). After isoelectric point separation is completed, the temperature is lowered to −25 ° C., the liquid samples in the first separation channel 101 and the second separation channel 102 are frozen, and then evacuated for about 15 minutes. Thereby, freeze-drying is performed. Finally, the temperature is raised to 30 ° C. and waits for 2 minutes, and the liquid components in the first separation channel 101 and the second separation channel 102 are completely dried.

  As a result, the separated components are dried and fixed in a predetermined region partitioned by the first partition plate 200 (S15 in FIG. 1). In the first separation channel 101 and the second separation channel 102, for example, first partition plates 200 are formed every 500 μm. Therefore, the amphoteric component in the liquid sample exists in a freeze-dried state for each 500 μm section formed between the first partition plates 200. If the interval between the first partition plates 200 is made small, a microarray chip with better resolution can be obtained.

  Here, the isoelectric point separation with the upper surface 202 of the flow path opened is described as an example. However, as another method, for example, a micro seal using a peelable seal such as PDMS (polydimethylsiloxane) is used. Isoelectric point separation may be performed with the top surface of the chip 100 sealed. In this case, after separation, the microchip 100 is cooled to −25 ° C., the liquid in the first separation channel 101 and the second separation channel 102 is frozen, and then the PDMS seal is peeled off, followed by freezing. Drying may be performed. The lid is not limited to PDMS, and any lid that can be peeled after the separation operation can be used.

  Next, in order to perform a binding reaction using a liquid reagent containing a binding substance that forms a complex with a predetermined component, the liquid reagent is added to the first separation channel 101 (S17 in FIG. 1). The method for adding the liquid reagent is appropriately selected. However, if the amount of the liquid to be added is too large, the liquid reagent overflows to the adjacent compartment beyond the first partition plate 200. For this reason, as the addition method, a simple pipetting method may be used, but a suitable material can be used from among ink jets, atomizers, ultrasonic sprayers, dispensers and the like that can limit the liquid amount to a higher degree. In this way, when the liquid reagent is added, it is more effective that the components existing in the predetermined region partitioned by the first partition plate 200 diffuse beyond the first partition plate 200 to other partitions. Can be suppressed.

  The liquid reagent includes, for example, a binding substance and a buffer. As the buffer, a solution system used in normal biological experiments such as PBS (Phosphate Buffered Saline) and TBS (Tris Buffered Saline) can be used.

  The amphoteric component after separation is fixed in a predetermined section of the flow path in a dry state, and the added liquid reagent soaks into the amphoteric component if the amount is small. Since the binding reaction solution needs to be kept in a liquid state for the time required for the complex formation reaction (binding reaction), even if the microchip 100 is placed in a humidity chamber near 100% humidity, it is allowed to stand still. Good. The buffer, temperature, and reaction time of the binding reaction are optimized depending on the properties of the components contained in the liquid reagent.

  After the binding reaction, the temperature of the microchip 100 is raised in an atmosphere such as dry air, or freeze drying is performed to completely dry the components in the first separation channel 101 again.

  The second separation channel 102 used as the reference separation channel is separated under the same conditions as the first separation channel 101, and is used as a reference without being subjected to the binding reaction.

  Next, the matrix solution is added to the first separation channel 101 and the second separation channel 102. As the matrix solution, for example, a sinapinic acid saturated solution using 0.3% trifluoroacetic acid + 30% acetonitrile solvent can be used. As an addition method, a simple pipetting method may be used, but a suitable material can be used from among ink jets, atomizers, ultrasonic sprayers, dispensers and the like that can further limit the amount of liquid. In this way, when the matrix solution is added, it is more effective that the components existing in the predetermined region partitioned by the first partition plate 200 diffuse beyond the first partition plate 200 to other regions. Can be suppressed. Furthermore, it is preferable to set the concentration of the organic solvent in the matrix solution as low as possible from the viewpoint of making it difficult for the complex to be detached.

  Thereafter, the microchip 100 having the first separation channel 101 and the second separation channel 102 is mounted on the MALDI mass spectrometer target holder and set on the microchip 100 from one end to the other end. Mass analysis is performed on the central portion of each region (S19 in FIG. 1).

  After the measurement, for each region, the mass analysis results of the first separation channel 101 and the second separation channel 102 are compared with each other, and a portion where a difference in spectral peak occurs is searched. The component having a difference in the spectrum peak is a component that forms a complex with the substance in the liquid reagent. For searching, you may look at the chart with your eyes, but using a computer program for comparison gives a more convenient and reproducible result.

  As described above, it is possible to test whether the substance in the liquid reagent is bound to the component fixed in which region partitioned by the first partition plate 200 among the amphoteric components separated using the microchip 100. Further, since the separation position of the component in the flow path can be preserved and the formation position of the complex can be detected, the isoelectric point of the component that has formed the complex can be known. And a component can be specified or a candidate substance can be narrowed down from the mass data before and after complex formation of the component which forms a complex, and an isoelectric point.

  As described above, according to the present embodiment, after all the amphoteric components such as proteins and peptides contained in an arbitrary sample extracted from a living body are discretely arrayed, the arrayed amphoteric components can be easily obtained. Binding assays for other substances can be performed.

  In the following embodiment, it demonstrates centering on a different point from 1st embodiment.

(Second embodiment)
In the first embodiment, the case where the first partition plate 200 is provided on the flow path bottom surface 201 of the substrate 103 has been described as an example. However, the substrate 103 and the partition plate may be separate members. In the present embodiment, an example will be described in which a partition plate is provided on the lid portion disposed on the substrate 103. In this embodiment, the case where the partition plate is provided in the first separation channel 101 will be described as an example, but the same configuration can be applied to the second separation channel 102.

  Also in this embodiment, the substrate 103 having the basic configuration shown in FIG. 2 is used. However, the first partition plate 200 may not be provided in the first separation channel 101 and the second separation channel 102.

  In addition, the microchip of the present embodiment includes a lid portion 220 disposed on the upper part of the flow path forming surface of the substrate 103. FIG. 4A and FIG. 4B are diagrams showing the configuration of the lid. 4A is a plan view of the lid 220, and FIG. 4B is a cross-sectional view taken along the line BB ′ of FIG. 4A.

  The lid 220 shown in FIGS. 4A and 4B is used as a lid for the first separation channel 101. The lid 220 is detachably provided on the first separation channel 101. The material of the lid part 220 may be the same material as the substrate 103 or a different material. As the lid part 220, plastics such as a photocurable resin, stainless steel, etc. can be used in addition to those exemplified as the material of the substrate 103 in the first embodiment.

The microchip of this embodiment includes a second partition plate 221 provided on the lid 220 as a partition plate.
The second partition plate 221 is formed in a region corresponding to the first separation channel 101 when the lid 220 is disposed on the substrate 103. When the lid portion 220 is disposed on the substrate 103, the second partition plate 221 is configured to protrude into the first separation channel 101 over the entire width of the substrate 103.

  The lid portion 220 includes a plurality of second partition plates 221 arranged substantially in parallel and a support portion 222 that connects the plurality of second partition plates 221, and is sandwiched between a plurality of adjacent second partition plates 221. In the region, the first separation channel 101 is provided with an opening communicating with the outside. In this way, after the binding reaction, the matrix solution can be introduced into the flow path with the lid 220 provided. Further, the component separated into the region sandwiched between the second partition plates 221 can be directly irradiated with laser light for mass analysis. The second partition plate 221 and the support portion 222 are orthogonal to each other, and the planar shape of the lid portion 220 is a ladder shape.

  The protruding height of the second partition plate 221 is equal to or less than the depth H of the first separation channel 101. The height h2 of the second partition plate 221, that is, the protruding height from the flow channel upper surface 202 into the flow channel, is a predetermined value of the first separation flow channel 101 when the liquid reagent is introduced into the first separation flow channel 101. The component fixed in this area is set to a size that does not diffuse beyond the second partition plate 221 to other areas. For example, h2 is used in a range of h2 <H with respect to the depth H of the first separation channel 101. Moreover, it is preferable to set h2 = H from the viewpoint of further reliably suppressing the component fixed to the flow channel bottom surface 201 from diffusing in the flow channel extending direction beyond the second partition plate 221.

  In addition, when the lid portion 220 is disposed on the substrate 103, both side surfaces of the second partition plate 221 may be configured to contact both side walls of the first separation channel 101. Further, the width of the second partition plate 221 and the width of the first separation channel 101 may be substantially equal. If it carries out like this, when the component fix | immobilized in the area | region divided by the 2nd partition plate 221 contact | connects a liquid reagent, it can suppress more effectively that it diffuses over the 2nd partition plate 221. FIG.

  The distance between the centers of the plurality of second partition plates 221 and the length of the region partitioned by the second partition plate 221 in the flow path extending direction are set, for example, in the same manner as in the first embodiment.

Also in this embodiment, by providing the second partition plate 221, the same effect as that of the first embodiment can be obtained.
Furthermore, in the present embodiment, even if the first separation channel 101 is a concave channel without the first partition plate 200, the first separation channel 101 is disposed on the substrate 103 before the binding reaction, and the solution moves during the binding reaction. Can be prevented. For this reason, since it can be set as the state which does not provide the 2nd partition plate 221 in the flow path 101 for 1st separation at the time of isolation | separation, compared with the structure of 1st Embodiment which makes the 1st partition plate 200 in the board | substrate 103. Thus, the influence on the separated state due to the provision of the partition plate can be more reliably removed.

  In order to securely attach the lid portion 220 shown in FIG. 4 to a specific position of the microchip, a concave portion is formed in the substrate 103 and a shape corresponding to the concave portion of the lid portion 220 is formed. A convex part may be provided.

FIG. 9 is a plan view showing an example of the structure of a microchip having a recess. In FIG. 9, only the periphery of the first separation channel 101 of the substrate 103 is shown.
In FIG. 9, the substrate 103 is provided with a groove 240, and the lid 220 is provided with a protrusion (not shown) that fits into the 240. Specifically, a rectangular groove 240 surrounding the first separation channel 101 is formed with a suitable interval around the first separation channel 101. Then, by producing a convex portion (not shown) that can be fitted into the groove portion 240 at a position corresponding to the groove portion 240 of the lid portion 220, it is possible to mount them at a predetermined position. Further, the second partition plate 221 provided on the lid 220 can be disposed at a predetermined position of the first separation channel 101.

  In addition, the groove part 240 should just be able to detachably fix the cover part 220 to the predetermined position on the board | substrate 103, The planar shape is not necessarily restricted to a rectangular shape. For example, when the groove 240 has a shape including a plurality of corners of two or more, the lid 220 can be more reliably fixed on the substrate 103.

  Further, the recess provided in the substrate 103 is not limited to a groove shape (stripe shape), and may be a columnar hole, for example.

(Third embodiment)
In 1st and 2nd embodiment, although the structure which provides a partition plate in one of the board | substrate 103 and the cover part 220 was shown, you may use combining these. In the present embodiment, the configuration of the first separation channel 101 will be described below as an example, but the same configuration as the first separation channel 101 can be applied to the second separation channel 102 as well.

  FIG. 5A and FIG. 5B are diagrams showing the configuration of the first separation channel 101 of the microchip of this embodiment. 5A is a plan view of the first separation flow path 101, and FIG. 5B is a cross-sectional view taken along the line CC ′ of FIG. 5A.

  The microchip illustrated in FIGS. 5A and 5B includes both the substrate 103 illustrated in FIG. 3 and the lid portion 220 illustrated in FIG. 4. After separation without providing the lid 220, the lid 220 is disposed on the substrate 103 during the binding reaction, and these are used simultaneously. In addition, the partition plate is provided on the bottom surface of the first separation channel 101 and is opposed to the first partition plate 200 provided over the entire width of the first separation channel 101 and the upper portion of the first partition plate 200. And a second partition plate 221 provided.

  The first partition plate 200 and the second partition plate 221 are formed at positions facing each other when the lid portion 220 is disposed on the substrate 103. The lid portion 220 is provided so as to be detachable from the substrate 103, and is configured such that the first partition plate 200 and the second partition plate 221 are in contact with each other with the lid portion 220 disposed on the substrate 103. That is, the first partition plate 200 and the second partition plate 221 are abutted and have a meshing structure.

  h1 and h2 can be set under the condition satisfying h1 + h2 ≦ H. Note that the first partition plate 200 and the second partition plate 221 are configured such that when the lid portion 220 is disposed on the substrate 103, the movement of the liquid between the first region 171 and the second region 172 during the binding reaction. The first partition plate 200 and the second partition plate 221 are in contact with each other as long as they are suppressed. It is preferable that the flow path is blocked, that is, h1 + h2 = H. By doing so, the diffusion of components during the binding reaction can be prevented more reliably.

  In the present embodiment, since the first partition plate 200 and the second partition plate 221 are used in combination, even when the height of the first partition plate 200 is lowered, the first region 171 and the second region during the binding reaction are used. The movement of the liquid between 172 can be more effectively suppressed. By reducing the height of the first partition plate 200, the liquid sample can be more efficiently introduced into the entire first separation channel 101, and the influence on the separation can be reduced. After the components in the sample are separated by the first separation channel 101 provided with the first partition plate 200 having such a height h1, the second partition plate having a height h2 equal to the channel height H is obtained. By using the lid part 220 having 221, the binding reaction can be performed in a state in which the movement of the liquid is completely prevented.

(Fourth embodiment)
In the above embodiment, the first region 171 and the second region 172 may be provided with a structure for holding the liquid in the region. As such a structure, a plurality of pillars (columnar bodies) are provided in the present embodiment. Hereinafter, the configuration of the microchip of the first embodiment will be described as an example.

  FIGS. 6A and 6B are diagrams showing the configuration of the first separation channel 101 of the microchip of the present embodiment. 6A is a plan view of the first separation channel 101, and FIG. 6B is a cross-sectional view taken along the line DD ′ of FIG. 6A. In the present embodiment, the configuration of the first separation channel 101 will be described as an example, but the same configuration can be applied to the second separation channel 102.

  In FIG. 6A and FIG. 6B, a plurality of pillars 230 are provided in the center of the region partitioned by the first partition plate 200 of the first separation channel 101. Further, in the first region 171 and the second region 172 adjacent to each other with the first partition plate 200 interposed therebetween, a plurality of columnar bodies (pillars 230) are provided on the bottom surface of the first separation channel 101, and the plurality of pillars 230 The side wall is provided separately from the side wall of the first separation channel 101 and the first partition plate 200. By providing the plurality of pillars 230, moisture can be retained at the center of the region, so that solution movement during the binding reaction can be more effectively prevented. Further, by increasing the area of the flow path inner walls of the first region 171 and the second region 172, the liquid in these regions can be dried more rapidly.

The pillar 230 can be manufactured by a general fine processing method simultaneously with the first partition plate 200. The shape and interval of the pillar 230 are set to such an extent that the separation is not hindered.
For example, the height of the pillar 230 is configured to be lower than the depth of the first separation channel 101. Specifically, the height h3 of the pillar 230 is set to h3 <(2/3) H, preferably h3 ≦ (1/2) H. Further, the maximum width w of the pillar 230 is set in a range of 0.1 μm or more and 50 μm or less, for example.

  In FIG. 6, the pillar 230 has a cylindrical shape, but the shape of the pillar 230 is not particularly limited, and may be a rectangular column such as a square column.

(Fifth embodiment)
The present embodiment relates to another analysis method using the microchip described in the above embodiments. Hereinafter, a case where two microchips 100 (FIG. 2) described in the first embodiment are used will be described as an example.

FIG. 8A and FIG. 8B are plan views for explaining an analysis method using the microchip shown in FIG.
In the present embodiment, the first and second microchips 100 are used. Then, before the step 13 for separating the components, a liquid sample to be subjected to mass spectrometry is introduced into the first separation channel 101 and the second separation channel 102 of the first microchip 100, and these flow The method further includes the step of roughly separating the components in the liquid sample by isoelectric point separation in the channel. Further, the steps after step 13 for separating the components are performed in the second microchip 100. In the step 13 of separating the components, the components in the liquid sample are subjected to isoelectric point separation in a narrower pH region than in the step of roughly separating the components in the liquid sample by isoelectric point separation.

More specific description will be given below.
First, as shown in FIG. 8 (a), in order to test all amphoteric components in a liquid sample, isoelectric point separation is performed using an amphoteric carrier that forms a relatively wide range of pH gradients, for example, pH 3-10. Perform the test. As the test method, the method described above in the above embodiment is used.

However, a biological sample has a large number of proteins, and there is a high possibility that many components exist at the same position.
Therefore, when a positive candidate signal is obtained, isoelectric point separation is performed as a second step using an amphoteric carrier that contains a positive candidate signal and forms a relatively narrow range of pH gradient. It can be performed.

  For example, as shown in FIG. 8A, when a positive signal is detected in the spot 104 near pH 6, as shown in FIG. 8B, another microchip 100 having the same shape is used and pH 5 Reanalysis is performed using the amphoteric carrier of 7 or less. Thereby, the component in the spot 104 can be further finely separated, and the spot 105 of the component that forms a complex with the substance in the liquid reagent can be detected.

  In this embodiment, in order to narrow the separable pH region and re-test the same sample, the isoelectric point of less than pH 5 and more than pH 7 in the sample is used while using the same sample as the separation channel having the same shape. The components can be expelled into the liquid reservoirs at both ends of the separation channel, and as a result, the number of separated component species per unit length is further reduced, and a clearer test result can be given.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

  For example, one or more alignment marks may be provided on the flow path forming surface of the microchip described in the above embodiment. Thereby, the introduction of the liquid reagent used for the binding reaction and the alignment during mass spectrometry can be performed more accurately.

(Example 1)
Hereinafter, more specific examples will be described by taking the case of the microchip of the first embodiment as an example.
Quartz glass is used as the material of the substrate 103. On the substrate 103, two linear fine channels are formed in parallel by exposure and dry etching. Then, after ozone ashing the surface of the substrate 103, a polyolefin microsealing tape 9795 manufactured by 3M is used as a cover on the first separation channel 101 and the second separation channel 102.

  Isoelectric point separation of the sample is performed using the obtained microchip 100. A neutravidin aqueous solution is introduced as a sample to be analyzed from the liquid reservoir 150 and the liquid reservoir 152 communicating with the first separation channel 101 and the second separation channel 102. After being introduced for several minutes, the sample reaches the opposite liquid reservoir, that is, the liquid reservoir 151 and the liquid reservoir 153 by capillary action.

  Next, the positive side liquid reservoir is filled with a phosphoric acid solution, and the negative side liquid reservoir is filled with sodium hydroxide. The first electrode 160, the second electrode 161, the first electrode 162, and the second electrode 163 are disposed in the liquid reservoir 150, the liquid reservoir 151, the liquid reservoir 152, and the liquid reservoir 153, respectively. A DC voltage is applied between the electrodes. Specifically, a DC voltage of 2500 V is applied between the liquid reservoirs at both ends for a channel length of about 35 mm.

  Isoelectric point separation of the two lanes of the first separation channel 101 and the second separation channel 102 is performed in parallel. Isoelectric point separation is completed about 2 minutes after the start of energization. In the first separation channel 101 and the second separation channel 102, a convergence band of neutravidin is formed in one place. Neutravidin is separated into a region near pI6.3 among the regions partitioned by the first partition plate 200.

  Thereafter, the microchip 100 is moved onto a horizontal metal table (not shown) cooled with liquid nitrogen, and the liquid in the first separation channel 101 and the second separation channel 102 is frozen. When left standing for a while, the seal used as a lid is peeled off spontaneously. The frozen sample is freeze-dried to remove moisture, and neutravidin is fixed to the first separation channel 101 and the second separation channel 102 in a solid state.

On the other hand, a reaction solution in which a biotinylated peptide is dissolved in a PBS buffer is prepared in advance. The sequence of the peptide used here is
Biotin-LYPIANGNNQSPVDIK-COOH (SEQ ID NO: 1)
It is. Each amino acid residue is represented by one letter.

  The microchip 100 after lyophilization is placed on an XY electric stage, and alignment in the XY directions is performed using marks previously provided on the microchip 100. The XY electric stage is moved along the flow path, and the biotinylated peptide solution described above is added. For the addition, a dispenser capable of controlling the amount of coating is used.

  By allowing this to stand at room temperature, it takes about 5 minutes to dry, during which the binding reaction is completed. Thereafter, the microchip 100 is heated at 30 ° C. for 2 minutes to completely evaporate moisture.

In addition to the binding reaction, a saturated solution of sinapinic acid is prepared as a matrix.
And this matrix solution is sprayed with respect to the surface of the microchip 100 after drying. For example, when an atomizer is used, the matrix solution adheres to the surface of the microchip 100 and the separation channel in the form of small particles having a diameter of 500 μm or less. These adhere to the binding-reacted sample remaining in the first separation channel 101 of the microchip 100 and the non-binding reaction sample remaining in the reference second separation channel 102, and the powder is applied to the matrix. Dissolve in water droplets. At this time, when the ambient temperature is controlled and these are dried in several tens of seconds, each component once mixed with the matrix forms a mixed crystal through a drying process.

  The microchip 100 prepared by the above procedure is directly used as a target of a MALDI-TOF mass spectrometer. At this time, an adapter having the same shape as the standard target of the mass spectrometer may be manufactured, and measurement may be performed by mounting a microchip on the adapter. The adapter is mounted on a computer-controlled XY stage and is position-controlled by a controller computer.

  By performing mass spectrometry in a linear mode every 0.5 mm from one end of the first separation channel 101, a mass spectrum of the combined sample can be acquired. Similarly, by performing mass spectrometry from one end of the second separation channel 102, a mass spectrum for the unbound sample can be obtained.

  FIG. 7A and FIG. 7B are diagrams schematically showing each mass spectrum. FIG. 7A corresponds to the measurement result of the second separation channel 102, and FIG. 7B corresponds to the measurement result of the first separation channel 101.

  As shown in FIG. 7A, from the second separation channel 102 used as the reference channel, only the peak of neutravidin is at the convergence position, the position of m / z = [β] in the figure. Detected. When measured, a peak of what appears to be a monomer is strongly detected in the vicinity of m / z = 14511 (= [β]) in addition to a peak derived from a tetramer of neutravidin (not shown).

  Further, when a mass spectrum for the combined sample of the first separation channel 101 is acquired in a state where measurement conditions such as laser intensity are optimized, as shown in FIG. 7B, the first separation channel 101 is obtained. From the whole, a mass peak of biotinylated peptide is obtained in the vicinity of m / z = 1968 (= [α]).

  Furthermore, at a position where neutravidin has converged by isoelectric point separation, a peak can be detected in the vicinity of m / z = 16480 where neutravidin and biotinylated peptide are considered to be bound. This value agrees well with the sum of the mass-to-charge ratios of each molecule.

  Actually, the binding reaction does not proceed 100%, and peak signals of m / z = 14511 and m / z = 1968 corresponding to the single masses of both components are also detected at the same time. Neutravidin is a tetramer, and a similar peak shift (not shown) is observed at a position of about 58 kD, but its signal intensity is low, and a signal considered to be a monomer is strongly observed.

  By comparing the mass spectra of the first separation channel 101 and the second separation channel 102 acquired in this manner, it is possible to detect at which position the binding test sample is bound. In some cases, another element having a value close to the mass-to-charge ratio of the conjugate may be present at the same position, but the resolution of the mass spectrometer is usually high enough to distinguish them.

  In addition, about the identification of the peak which showed positive here, the method which performs the peptide mass fingerprint method on a flow path, 2D-PAGE (two-dimensional polyacrylamide gel electrophoresis) targeting the applicable isoelectric point area | region, and the past A precision analysis method such as column operation is used.

  In addition, by using the method of the present embodiment, a liquid sample containing a larger number of components can be reliably separated in the flow path and can be immobilized in different regions partitioned by the first partition plate 200. it can. The presence or absence of formation of a complex with the substance in the liquid reagent can be detected for each component immobilized in different regions.

  In this embodiment, the case where the liquid sample contains a component that forms a complex with the binding reagent has been described. However, mass spectrometry obtained for the first separation channel 101 and the second separation channel 102 was used. If no peak shift occurs in the spectrum, it can be seen that such a component is not contained in the liquid sample.

It is a flowchart which shows the analysis procedure in embodiment. It is a top view which shows the structure of the microchip in embodiment. It is a figure which shows the structure of the flow path for isolation | separation of the microchip of FIG. It is a figure which shows the structure of the flow path for isolation | separation of the microchip of FIG. It is a figure which shows the structure of the flow path for isolation | separation of the microchip of FIG. It is a figure which shows the structure of the flow path for isolation | separation of the microchip of FIG. It is a figure which shows the example of isolation | separation of the sample in an Example. It is a figure explaining the analysis method using the microchip in an embodiment. It is a top view which shows the structure of the separation channel of the microchip of FIG.

Explanation of symbols

100 Microchip 101 First Separation Channel 102 Second Separation Channel 103 Substrate 104 Spot 105 Spot 150 Liquid Reservoir 151 Liquid Reservoir 152 Liquid Reservoir 153 Liquid Reservoir 160 First Electrode 161 Second Electrode 162 First Electrode 163 Second Electrode 171 1st area | region 172 2nd area | region 200 1st partition plate 201 Flow path bottom face 202 Flow path upper surface 203 Flow path side wall 220 Lid part 221 2nd partition plate 222 Support part 230 Pillar 240 Groove part

Claims (16)

A substrate,
A flow path provided in a groove shape on the substrate;
A partition plate provided in the flow path;
Including
The liquid sample is introduced over the entire flow path, and the components in the liquid sample are separated into the first and second regions partitioned by the partition plate based on a predetermined property, and are fixed.
A liquid reagent containing a substance that forms a complex with a predetermined component is introduced into the first and second regions of the flow path,
The partition plate is
Provided over the entire width of the flow path,
When the components separated and immobilized in the first and second regions in the flow path come into contact with the liquid reagent, they pass from one of the first and second regions to the other over the partition plate. A microchip configured to suppress diffusion. The microchip according to claim 1, wherein
A microchip in which a side wall of the flow path and the partition plate are provided continuously. The microchip according to claim 1 or 2,
The partition plate includes a first partition plate provided on the bottom surface of the flow path,
A microchip in which the height of the first partition plate is lower than the depth of the flow path. The microchip according to claim 3, wherein
A microchip in which a plurality of the first partition plates are arranged along an extending direction of the flow path. The microchip according to any one of claims 1 to 4,
In the first and second regions, a plurality of columnar bodies are provided on the bottom surface of the flow path,
The microchip in which the side walls of the plurality of columnar bodies are provided separately from the side walls of the flow path and the partition plate. The microchip according to claim 1, wherein
The flow path includes an isoelectric separation region where a pH gradient is formed;
The first and second regions are provided in the isoelectric point separation region;
A microchip further comprising a pair of electrodes for applying an electric field to the isoelectric point separation region. The microchip according to any one of claims 1 to 6,
Including a lid disposed on an upper surface of the flow path of the substrate;
The partition plate includes a second partition plate provided on the lid,
A microchip configured such that when the lid is disposed on the substrate, the second partition plate projects into the flow path over the entire width of the flow path. The microchip according to claim 7, wherein
The lid is
A plurality of the second partition plates arranged substantially in parallel;
A support portion for supporting the plurality of second partition plates;
Including
A microchip in which an opening communicating with the outside is provided in the flow path in a region sandwiched between the plurality of adjacent second partition plates. The microchip according to claim 7 or 8,
A groove is provided in the substrate;
A microchip in which a protrusion that fits into the groove is provided on the lid. The microchip according to any one of claims 7 to 9,
The partition plate is provided on the bottom surface of the flow path, and includes a first partition plate provided over the entire width of the flow path,
The microchip, wherein the second partition plate is provided to face an upper portion of the first partition plate. The microchip according to any one of claims 1 to 10,
A microchip used as a target plate for mass spectrometry. The microchip according to any one of claims 1 to 11,
The flow path;
A reference channel provided in the vicinity of the channel, and provided along the channel;
Including
The partition plate is provided in the flow path and the reference flow path,
A microchip in which the partition plate of the reference channel is provided at a position corresponding to the partition plate provided in the channel. A method of using the microchip according to any one of claims 1 to 12,
Introducing a liquid sample to be subjected to mass spectrometry into the flow path, and separating components in the liquid sample into the first and second regions;
After the step of separating components, immobilizing the separated components in the first and second regions;
After the step of immobilizing a component, a liquid containing a substance that forms a complex with a predetermined component in the flow path in a state where the partition plate is disposed between the first region and the second region. Introducing a reagent to form a complex of the predetermined component and the substance;
How to use a microchip containing The method of using the microchip according to claim 13,
Performing laser desorption ionization mass spectrometry of the liquid sample after the step of forming a complex,
The step of performing laser desorption ionization mass spectrometry comprises:
Irradiating the flow path with laser light to obtain a first mass spectrometry spectrum, based on the first mass spectrometry spectrum, detecting the presence or absence of formation of the complex in the first and second regions;
How to use a microchip containing A method of using the microchip according to claim 12,
Introducing a liquid sample to be subjected to mass spectrometry into the flow path and the reference flow path, and separating components in the liquid sample into the first and second regions;
After the step of separating components, immobilizing the separated components in the first and second regions;
After the step of immobilizing a component, a liquid containing a substance that forms a complex with a predetermined component in the flow path in a state where the partition plate is disposed between the first region and the second region. Introducing a reagent to form a complex of the predetermined component and the substance;
After the step of forming a complex, performing laser desorption ionization mass spectrometry of the liquid sample;
Including
The step of performing laser desorption ionization mass spectrometry comprises:
Irradiating the channel with laser light to obtain a first mass spectrometry spectrum;
Irradiating the reference channel with laser light to obtain a second mass spectrometry spectrum;
Comparing the first mass spectrometry spectrum and the second mass spectrometry spectrum to detect the formation of the complex in the first and second regions of the flow path;
How to use a microchip containing The method of using the microchip according to any one of claims 13 to 15,
Using the first and second microchips,
Before the step of separating the components, a liquid sample to be subjected to mass spectrometry is introduced into the flow path of the first microchip, and the components in the liquid sample are coarsened by isoelectric point separation in the flow path. Further comprising the step of separating,
Performing the steps after the step of separating the components in the second microchip,
A method of using a microchip, wherein in the step of separating components, the components in the liquid sample are subjected to isoelectric point separation in a narrower pH region than in the step of roughly separating the components in the liquid sample by isoelectric point separation.

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