High-voltage power supply device for microchip electrophoresis device and microchip electrophoresis device

Abstract

A high-voltage power supply device capable of supplying a high voltage to a microchip electrophoresis device is provided with: a substrate; a plurality of high voltage generation circuits disposed on the upper surface (first surface) of the substrate; and a plate-shaped shield member disposed on the first surface side of the substrate. Each high-voltage generation circuit has a transformer, a plurality of high-voltage generation circuits are disposed between the first surface of the substrate and the shield member (2), and the plate surface of the shield member is disposed parallel to the coil axis of each transformer.

Description

High-voltage power supply for microchip electrophoresis apparatus and microchip electrophoresis apparatus Technical Field

[0001] The present invention relates to a power supply device for supplying high voltage to a microchip electrophoresis apparatus, and a microchip electrophoresis apparatus having the power supply device. Background Technology

[0002] A sample analysis method utilizing microchip electrophoresis is known. In a microchip electrophoresis apparatus, a sample solution is injected into microchannels formed on a microchip. Electrophoresis then occurs by applying a high voltage (several kV, tens of kV) across the channels containing the sample solution. Through electrophoresis, components (charged substances) contained in the sample solution are separated based on differences in migration rates according to size. The components separated by electrophoresis are detected by a detector. Microchip electrophoresis can be used to analyze substances such as DNA or proteins, for example.

[0003] A microchip electrophoresis device is disclosed in the following patent document 1.

[0004] Prior art literature, patent literature, patent literature 1: Japanese Patent Application Publication No. 2023-105739 Summary of the Invention The technical problem to be solved by the invention is that a microchip electrophoresis apparatus includes a high-voltage power supply device for applying high voltage to terminals disposed on a microchip. Since multiple terminals are disposed in the flow channels formed on the microchip, the high-voltage power supply device includes multiple high-voltage generation circuits corresponding to the multiple terminals.

[0005] Multiple high-voltage generation circuits each have high-voltage output terminals. Even when a single high-voltage generation circuit outputs high voltage, and the stability and response speed are within specifications, the ripple of the output voltage increases when multiple high-voltage generation circuits output high voltage from their respective terminals. This is because high-voltage generation circuits located in adjacent positions are affected by mutual noise. In microchip electrophoresis, analysis is performed while high voltage is applied to multiple electrode terminals on the microchip; therefore, the ripple of the voltage output from the high-voltage generation circuit increases. If the output voltage ripple of the high-voltage generation circuit increases, the velocity of the material moving through electrophoresis becomes unstable, thus becoming a major factor reducing the accuracy of sample separation.

[0006] Specifically, this is because the transformer used in the high-voltage generation circuit radiates induced noise by generating high voltage, which in turn affects adjacent high-voltage generation circuits. While it is possible to suppress the noise effect by increasing the distance between the circuits, the size of the device makes it difficult to ensure a distance sufficient to reduce the impact of induced noise.

[0007] The purpose of this invention is to reduce the impact of noise from adjacent high-voltage generation circuits in a power supply device that supplies high voltage to a microchip electrophoresis apparatus.

[0008] According to one aspect of the present invention, a high-voltage power supply device for a microchip electrophoresis apparatus is a high-voltage power supply device capable of supplying high voltage to a microchip electrophoresis apparatus, comprising: a substrate; a plurality of high-voltage generating circuits disposed on a first surface of the substrate; and a plate-shaped shielding member disposed on the first surface of the substrate. Each high-voltage generating circuit has a transformer, and the plurality of high-voltage generating circuits are disposed between the first surface of the substrate and the shielding member, wherein the plate surface of the shielding member is configured to be parallel to the coil axis of each transformer.

[0009] The present invention also relates to a microchip electrophoresis apparatus having the above-mentioned high-voltage power supply device.

[0010] According to the present invention, in a power supply device that supplies high voltage to a microchip electrophoresis apparatus, the effects of noise from an adjacent high voltage generation circuit can be reduced. Attached Figure Description

[0011] [Figure 1] Figure 1 is an overall diagram of the microchip electrophoresis apparatus according to this embodiment.

[0012] [Figure 2] Figure 2 is a diagram showing the internal structure of a microchip.

[0013] [Figure 3] Figure 3 is a top view showing the high-voltage power supply device according to this embodiment.

[0014] [Figure 4] Figure 4 is a cross-sectional view of the IV-IV side of the high-voltage power supply unit shown in Figure 3. Detailed Implementation

[0015] Next, the configuration of the high-voltage power supply device 1 and the microchip electrophoresis device ME according to this embodiment will be described with reference to the accompanying drawings.

[0016] (1) Overall configuration of the microchip electrophoresis apparatus Figure 1 is an overall view showing the microchip electrophoresis apparatus ME according to this embodiment. The microchip electrophoresis apparatus ME includes a high-voltage power supply device 1, a supply unit 6, a microchip 7, a detector 8, and a control unit 9. The high-voltage power supply device 1 is an example of the high-voltage power supply device for the microchip electrophoresis apparatus of the present invention.

[0017] A high-voltage power supply unit 1 applies high voltage to multiple electrode terminals disposed on the microchip 7. A supply unit 6 supplies the microchip 7 with the sample solution of the analyte, separation buffer, and washing solution. The microchip 7 holds the sample solution of the analyte. Components (charged substances) contained in the sample solution held in the microchip 7 move and separate through electrophoresis. A detector 8 detects the components that move and separate through electrophoresis within the microchip 7. A control unit 9 controls the various functional units of the microchip electrophoresis apparatus ME, including the high-voltage power supply unit 1, the supply unit 6, and the detector 8.

[0018] (2) Structure of the Microchip The structure of the microchip 7 is described with reference to Figures 1 and 2. As shown in Figure 1, the microchip 7 is composed of a generally rectangular plate-shaped component. Four electrode terminals 71a, 71b, 71c, and 71d are arranged on the surface of the plate of the microchip 7. The four electrode terminals 71a to 71d are respectively connected to the high-voltage power supply device 1. Thus, high voltage can be applied to the electrode terminals 71a to 71d respectively through the high-voltage power supply device 1.

[0019] Figure 2 shows the internal structure of the microchip 7. As shown in Figure 2, two flow channels (capillaries) 73 and 74 for holding the sample solution are formed inside the microchip 7. Flow channels 73 and 74 intersect each other, forming a cross-shaped flow channel. Flow channel 73 is used to guide the sample solution of the analyte to flow channel 74. Flow channel 74 is used as a separation flow channel for separating the sample solution of the analyte by electrophoresis.

[0020] Reservoirs 75a and 75b are provided at both ends of flow channel 73. Reservoirs 75c and 75d are provided at both ends of flow channel 74. Reservoirs 75a, 75b, 75c, and 75d are spaces for supplying and aspirating separation buffer and sample solution. Reservoirs 75a, 75b, 75c, and 75d have cylindrical spaces extending vertically relative to the surface of microchip 7. Flow channels 73 and 74 and reservoirs 75a to 75d with this configuration are formed inside microchip 7.

[0021] Furthermore, as shown in Figure 1, electrode terminals 71a and 71b are respectively disposed in the liquid reservoirs 75a and 75b located at both ends of the flow channel 73. That is, electrode terminals 71a and 71b are disposed at the ends of the liquid reservoirs 75a and 75b extending in a direction perpendicular to the surface of the microchip 7. Furthermore, as shown in Figure 1, electrode terminals 71c and 71d are respectively disposed in the liquid reservoirs 75c and 75d located at both ends of the flow channel 74. Similarly, electrode terminals 71c and 71d are disposed at the ends of the liquid reservoirs 75c and 75d extending in a direction perpendicular to the surface of the microchip 7.

[0022] In the microchip electrophoresis apparatus ME, electrophoresis is performed by applying voltage from the high-voltage power supply 1 to the electrode terminals 71a to 71d provided in the flow channels 73 and 74. The voltage applied to the electrode terminals 71a to 71d is controlled by the control unit 9.

[0023] Sample analysis using the microchip electrophoresis apparatus ME is performed according to the following steps. First, separation buffer is filled into the entire interior of channels 73 and 74 by the supply unit 6. The separation buffer is also used as a "separation medium" and may contain, for example, a pH buffer and a water-soluble polymer (such as a cellulose polymer). Next, the sample solution of the analyte is supplied to the reservoir 75a of channel 73 by the supply unit 6. A fluorescent dye is mixed in the sample solution. Then, an electric field gradient is applied to the electrode terminals 71a to 71d by the high-voltage power supply device 1, thereby creating an electric field gradient within channels 73 and 74. As a result, the sample solution moves within channel 73 to the position where channel 73 and channel 74 intersect. Afterward, by changing the magnitude of the voltage applied from the high-voltage power supply device 1 to each of the electrode terminals 71a to 71d, the sample solution is separated by electrophoresis within channel 74 while moving towards electrode terminal 71d (reservoir 75d). For example, in the case where the sample is a gene, since the gene carries a negative charge, it moves towards the anode direction when an electric field is applied.

[0024] In the analysis process performed by electrophoresis, the components in the sample solution move at different speeds within the flow channel 74 according to their size. For example, the migration speed of a gene is inversely proportional to its radius. Therefore, the size of a gene can be identified based on the applied voltage and arrival time. In the microchip electrophoresis apparatus ME, the detector 8 sequentially detects the components arriving at the detection position 76 within the flow channel 74. In this way, the components in the sample solution are detected according to their degree of separation (degree of electrophoresis) in the microchip electrophoresis apparatus ME.

[0025] Detector 8, for example, performs fluorescence detection on components separated by electrophoresis. Detector 8 has an LED (light-emitting diode) that illuminates excitation light at a detection position 76 in the flow channel 74. Then, by illuminating each component moving within the flow channel 74 while being separated by electrophoresis with excitation light from the LED, each component is excited and emits fluorescence. Detector 8, for example, uses a photomultiplier tube to measure this fluorescence via an optical fiber and a filter, thereby detecting the components separated by electrophoresis.

[0026] (3) Configuration of the High-Voltage Power Supply Device Next, the configuration of the high-voltage power supply device 1 according to this embodiment will be described with reference to Figures 3 and 4. Figure 3 is a top view showing the high-voltage power supply device 1 according to this embodiment. Figure 4 is a cross-sectional view of the high-voltage power supply device 1 along side IV-IV shown in Figure 3. In the high-voltage power supply device 1, the vertical direction is not specifically defined, but in the following description, for convenience, the XY plane in Figures 3 and 4 will be used as the horizontal direction of the high-voltage power supply device 1, and the Z direction will be used as the upward direction of the high-voltage power supply device 1.

[0027] As shown in Figures 3 and 4, four high-voltage generating circuits 11 are disposed on the upper surface 10U of the substrate 10 of the high-voltage power supply device 1. The upper surface 10U of the substrate 10 is an example of the first surface in this invention. The substrate 10 is configured to be parallel to the XY plane. Therefore, the upper surface 10U (first surface) of the substrate 10 is also parallel to the XY plane. Each of the four high-voltage generating circuits 11 has a transformer 12. The four high-voltage generating circuits 11 correspond to the four electrode terminals 71a to 71d of the microchip 7. By controlling the four high-voltage generating circuits 11 respectively by the control unit 9, high voltage can be applied to the four electrode terminals 71a to 71d.

[0028] An input terminal 17 and an output terminal 18 are provided on the substrate 10 of the high-voltage power supply device 1. The power input from the input terminal 17 is converted into voltage in the transformer 12 of the high-voltage generation circuit 11 and then output from the output terminal 18. The output terminal 18 is connected to the electrode terminals 71a to 71d of the microchip 7 shown in FIG1 via an output line.

[0029] As shown in Figure 3, the high-voltage power supply device 1 includes two spacers 15. Holes for mounting the spacers 15 are provided at two locations on the substrate 10. As shown in Figure 4, the spacers 15 are cylindrical members, and the shielding member 2 is supported by the two spacers 15. The shielding member 2 is a rectangular plate in plan view. In this embodiment, the shielding member 2 is made of copper. The two spacers 15 are made of conductive members, and the lower ends of the spacers 15 are connected to GND via conductive members formed on the substrate 10.

[0030] In this embodiment, since the substrate 10 and the shielding member 2 are arranged parallel to each other, the shielding member 2 is also parallel to the XY plane. That is, the upper surface (first surface) 10U of the substrate 10 is arranged parallel to the surface of the shielding member 2. The length of the shielding member 2 in the Y direction is approximately the same as the length of the substrate 10 in the Y direction, and in the Y direction, the shielding member 2 covers the entire substrate 10. In contrast, the length of the shielding member 2 in the X direction is shorter than the length of the substrate 10 in the X direction, and in the X direction, the shielding member 2 has a length sufficient to cover the transformer 12. Thus, in a plan view, the shielding member 2 is configured to overlap with the four transformers 12.

[0031] In Figure 3, direction D represents the axial direction of transformer 12. That is, the coil of transformer 12 is wound around an axis with direction D as its center. In this embodiment, direction D is aligned with the Y direction. Therefore, the axial direction D of transformer 12 is parallel to the upper surface 10U of substrate 10 and the surface of shielding member 2. In this embodiment, the axial directions of all four transformers 12 are direction D. That is, the axial directions of all four transformers 12 are in the Y direction.

[0032] Thus, in the high-voltage power supply device 1 of this embodiment, since a shielding member 2 is provided above the transformer 12, the voltage ripple output from each high-voltage generating circuit 11 can be reduced. This is because a portion of the induced noise emitted from the transformer 12 is converted into energy and dissipated inside the shielding member 2. In particular, in this embodiment, a plurality of transformers 12 are arranged between the upper surface (first surface) 10U of the substrate 10 and the shielding member 2, and the plate surface of the shielding member 2 is arranged parallel to the coil axis of each transformer 12, thereby effectively reducing the mutual noise influence between each high-voltage generating circuit 11. That is, the induced noise reaching each other between adjacent high-voltage generating circuits 11 is reduced, and the output voltage ripple can be reduced, similar to the case where a single high-voltage generating circuit 11 outputs high voltage from a single output terminal.

[0033] Furthermore, in the above embodiment, since the coil shafts of all transformers 12 are arranged along direction D (a common first direction), the induced noise reaching each other between adjacent high-voltage generation circuits 11 is more effectively reduced. Moreover, when viewed from a direction perpendicular to the upper surface (first surface) 10U of the substrate 10, the shielding member 2 overlaps with all four transformers 12. That is, since the shielding member 2 covers the entirety of the four transformers 12 in a plan view, the induced noise emitted from the transformers 12 is effectively consumed within the shielding member 2.

[0034] Furthermore, in this embodiment, since the shielding member 2 is connected to the GND of the substrate 10 via the spacer 15, the induced noise energy emitted from the transformer 12 flows from the shielding member 2 to the GND via the spacer 15.

[0035] (4) Other Embodiments In the above embodiments, a microchip electrophoresis apparatus ME having a set of microchips 7 and a high-voltage power supply device 1 was described as an example. The present invention is also applicable when the microchip electrophoresis apparatus ME has multiple microchips 7. When the microchip electrophoresis apparatus ME has multiple microchips 7, multiple high-voltage power supply devices 1 are provided corresponding to the multiple microchips 7. By having the configuration described in the above embodiments, the high-voltage generation circuit 11 of each high-voltage power supply device 1 can supply a voltage with low ripple to each microchip 7.

[0036] As described in the above embodiments, the shielding member 2 is made of a conductive component, such as copper, in order to direct the energy of induced noise to the GND of the substrate 10. Therefore, for example, a portion of the substrate material used to manufacture the substrate 10 can be used to make the shielding member 2. As a result, since a portion of the waste components generated during the manufacture of the substrate 10 can be used, it also helps to reduce costs.

[0037] In the above embodiment, the example described is that the length of the shielding member 2 in the Y direction is the same as the length of the substrate 10 in the Y direction. The length of the shielding member 2 in the Y direction is not limited to this example; it may be shorter or longer than the length of the substrate 10 in the Y direction. However, ideally, when viewed from a direction perpendicular to the upper surface 10U of the substrate 10, the shielding member 2 has a Y-direction length sufficient to overlap with all the transformers 12.

[0038] (5) As those skilled in the art should understand, the above-described exemplary embodiments are specific examples of the following methods.

[0039] (Item 1) One aspect of the present invention relates to a high-voltage power supply device for a microchip electrophoresis apparatus, which is a high-voltage power supply device capable of supplying high voltage to a microchip electrophoresis apparatus, comprising: a substrate; a plurality of high-voltage generating circuits disposed on a first surface of the substrate; and a plate-shaped shielding member disposed on the first surface side of the substrate, each high-voltage generating circuit having a transformer, the plurality of high-voltage generating circuits being disposed between the first surface of the substrate and the shielding member, and the plate surface of the shielding member being configured to be parallel to the coil axis of each transformer.

[0040] In the power supply device that supplies high voltage to the microchip electrophoresis apparatus, the noise effect on the high voltage generation circuit can be reduced.

[0041] (Item 2) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein the coil shafts of each transformer may also be arranged along a common first direction.

[0042] It can effectively reduce the noise impact on the high voltage generation circuit.

[0043] (Item 3) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein the coil shafts of each transformer may also be configured to be parallel to the first surface.

[0044] The structure, in which the substrate and shielding components are arranged in parallel, can effectively reduce the impact of noise on the high-voltage generation circuit.

[0045] (Item 4) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein, when viewed from a direction perpendicular to the first surface, the shielding component and each transformer may overlap.

[0046] Because each transformer is covered by shielding components, the noise impact on the high-voltage generation circuit can be effectively reduced.

[0047] (Item 5) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein the shielding component can also be connected to the GND of the substrate via a spacer.

[0048] It can release the noise energy received by the shielding component to the substrate side.

[0049] (Item 6) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein each high-voltage generation circuit can also be used to supply high voltage to any one of a plurality of electrode terminals disposed at the end of the flow channel in the microchip electrophoresis apparatus.

[0050] The voltage ripple supplied to each electrode terminal of the microchip is reduced, thus improving the analysis accuracy.

[0051] (Item 7) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein the shielding component may also contain copper.

[0052] It can effectively consume the induced noise generated by the transformer.

[0053] (Item 8) A high-voltage power supply device for a microchip electrophoresis apparatus according to Item 1, wherein the shielding component may also include the same components as the substrate.

[0054] It can effectively utilize the waste materials generated during substrate manufacturing.

[0055] (Item 9) Another aspect of the present invention relates to a microchip electrophoresis apparatus comprising a high-voltage power supply device for a microchip electrophoresis apparatus as described in any one of items 1 to 8.

[0056] It can provide microchip electrophoresis devices with high analytical precision.

Claims

1. A high-voltage power supply device for a microchip electrophoresis apparatus, characterized in that it is a high-voltage power supply device capable of supplying high voltage to the microchip electrophoresis apparatus, and that... The device comprises: a substrate; a plurality of high-voltage generating circuits disposed on a first surface of the substrate; and a plate-shaped shielding member disposed on the first surface side of the substrate, each high-voltage generating circuit having a transformer, the plurality of high-voltage generating circuits being disposed between the first surface of the substrate and the shielding member, and the plate surface of the shielding member being configured to be parallel to the coil axis of each transformer.

2. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, The coil shafts of each transformer are arranged along a common first direction.

3. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, The coil shafts of each transformer are configured to be parallel to the first surface.

4. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, When viewed from a direction perpendicular to the first surface, the shielding component overlaps with each transformer.

5. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, The shielding component is connected to the GND of the substrate via a spacer.

6. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, Each high-voltage generation circuit is used to supply high voltage to any one of the multiple electrode terminals located at the end of the flow channel in the microchip electrophoresis apparatus.

7. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, The shielding component contains copper.

8. The high-voltage power supply device for the microchip electrophoresis apparatus according to claim 1, characterized in that, The shielding component comprises the same components as the substrate.

9. A microchip electrophoresis apparatus, characterized in that, A high-voltage power supply device for a microchip electrophoresis apparatus according to any one of claims 1 to 8.

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