JP4957336B2 - Biopolymer analyzer and biopolymer analysis method - Google Patents

Description

  The present invention relates to a biopolymer analyzer and a biopolymer analysis method, and more particularly to a biopolymer analyzer and a biopolymer analysis method using a solid-state imaging device.

  In order to analyze the expression of genes of various biological species, biopolymer analysis microarrays such as DNA microarrays and antibody microarrays and readers thereof have been developed. The biopolymer analysis microarray is obtained by aligning and fixing cDNA and antibodies having a known base sequence serving as a probe on a solid support such as a slide glass in a matrix. For example, gene expression analysis using a DNA microarray and its reader is performed as follows.

First, a DNA microarray in which a plurality of types of cDNA having a known base sequence (hereinafter referred to as probe DNA) are aligned and fixed on a solid support such as a slide glass is prepared.
Next, mRNA is extracted from the specimen, cDNA is synthesized using reverse transcriptase, and prepared by labeling with a labeling substance (hereinafter referred to as labeled DNA). Here, as the labeling substance, a phosphor, a chemiluminescent substrate, an enzyme that emits light from the chemiluminescent substrate, or the like can be used.
Next, when the labeled DNA is added onto the DNA microarray, the labeled DNA is immobilized on the DNA microarray by hybridizing with the complementary probe DNA.
Next, the DNA microarray is set in the reader and analyzed by the reader (see, for example, Patent Document 1). The reading device irradiates the DNA microarray with an excitation light beam while moving the DNA microarray in the X direction and the Y direction orthogonal thereto, and condenses the light emitted from the labeling substance on the photomultiplier by the condensing lens. By measuring the intensity with a photomultiplier, the light intensity distribution in the surface of the DNA microarray is measured. Thereby, the light intensity distribution on the DNA microarray is output as a two-dimensional image. In the output image, the portion having a high light intensity indicates that a labeled DNA having a base sequence complementary to the base sequence of the probe DNA is included. Therefore, mRNA expressed in the specimen can be identified based on which part of the two-dimensional image has high fluorescence intensity.
JP2000-131237A

However, in order to analyze DNA using a DNA microarray, a small amount of sample DNA must be efficiently bound to the DNA of the DNA microarray.
Thus, an object of the present invention is to provide a biopolymer analyzer and a biopolymer analysis method that can efficiently bind a biopolymer of a sample.

In order to solve the above problems, the invention according to claim 1 is a biopolymer analyzer,
In a solid-state imaging device comprising a semiconductor film, a photosensor having a light-transmissive first gate electrode,
In the sensor detection mode, the first gate electrode is applied with a first voltage in order to accumulate carriers generated according to the amount of light incident on the semiconductor film,
In the target movement mode, the potential changes within a range where the potential difference is less than +30 V with respect to the first voltage and a positive second voltage is applied to attract the biopolymer charged with a negative charge.
It is characterized by.

The invention according to claim 2 is the biopolymer analyzer according to claim 1,
The photosensor includes a second gate electrode,
In the sensor detection mode, after applying the first voltage to the first gate electrode, a third voltage is applied to the second gate electrode in order to flow a current accompanying the action of the carrier after a predetermined time. It is characterized by that.

The invention according to claim 3 is the biopolymer analyzer according to claim 1 or 2,
A heating / cooling element for heating / cooling the solid-state imaging device;
Before the second voltage is applied to the first gate electrode, the heating and cooling element heats the solid-state imaging device,
When the second voltage is applied to the first gate electrode, the heating and cooling element cools the solid-state imaging device,
The heating / cooling element heats the solid-state imaging device after the second voltage is applied to the first gate electrode.

The invention according to claim 4 is the biopolymer analyzer according to any one of claims 1 to 3,
After the second voltage is applied to the first gate electrode, the temperature at which the heating / cooling element heats the solid-state imaging device is a biopolymer mishybridized with the probe fixed on the light receiving surface of the spot. It is the dissociation temperature which dissociates.

The invention according to claim 5 is a method for analyzing a biopolymer,
In a solid-state imaging device comprising a semiconductor film, a photosensor having a light-transmissive first gate electrode,
In the sensor detection mode, a first voltage is applied to the first gate electrode in order to accumulate carriers generated according to the amount of light incident on the semiconductor film,
In the target movement mode, the potential changes within a range where the potential difference is less than +30 V with respect to the first voltage in order to attract the biopolymer charged with a negative charge , and a positive second voltage is applied.
It is characterized by.

According to the present invention, a solution containing a biopolymer of a fluorescently labeled sample is dispersed on a protective insulating film of a solid-state imaging device, and a positive voltage is applied to at least one of a plurality of top gate lines by a top gate driver. When applied, the sample in solution moves. Therefore, the biopolymer can be efficiently guided to the spot using the constituent member of the solid-state imaging device, and the sample biopolymer is concentrated in the spot on the protective insulating film. Therefore, the sample biopolymer can be efficiently bound to the spot biopolymer.
Moreover, since the positive voltage applied to the top gate line can be set arbitrarily, the contact of the top gate line can be suppressed.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

[1] Overall Configuration of Biopolymer Analysis Chip FIG. 1 is a schematic perspective view of a biopolymer analysis chip 1 used in a biopolymer analysis apparatus according to an embodiment of the present invention, and FIG. 2 is this biopolymer analysis chip. 1 is a schematic plan view of FIG.
As shown in FIGS. 1 and 2, the biopolymer analysis chip 1 includes a solid-state imaging device 10, a frame-shaped partition wall 51 provided on the light-receiving surface side of the solid-state imaging device 10, and a light-receiving surface of the solid-state imaging device 10. , And the Peltier element 12 provided on the surface opposite to the light receiving surface of the solid-state imaging device 10.

[2] Solid-State Imaging Device Here, the solid-state imaging device 10 will be described with reference to FIGS. 2 and 3. FIG. 3 is a schematic cross-sectional view showing a developed cross-section along the line shown in FIG.
2 and 3, the solid-state imaging device 10 includes an insulating substrate 17, a bottom gate insulating film 22, a top gate insulating film 29, a protective insulating film 32, an excitation light absorbing layer 33, and spot fixing. The layer 35 is laminated. Between these layers, a plurality of bottom gate lines 41, source lines 42, drain lines 43, top gate lines 44, bottom gate electrodes 21, semiconductor films 23, channel protective films 24, impurity semiconductor films 25 and 26, source electrodes 27, A drain electrode 28 and a top gate electrode 31 (first gate electrode) are provided. Although details will be described later, the bottom gate electrode 21 (second gate electrode), the semiconductor film 23, the channel protective film 24, the impurity semiconductor films 25 and 26, the source electrode 27, the drain electrode 28, and the top gate electrode 31 are doubled. A gate type field effect thin film transistor 20 is formed.

  The insulating substrate 17 has a property of transmitting light (mainly visible light) emitted from a phosphor to be described later (hereinafter referred to as light transmitting property) and has an insulating property, and is a glass substrate such as quartz glass, polycarbonate, PMMA, or the like. It is a plastic substrate such as. That is, the insulating substrate 17 is a transparent substrate.

In this solid-state imaging device 10, a double gate type field effect thin film transistor (hereinafter referred to as a photosensor) 20 is used as a photoelectric conversion element, and a plurality of photosensors 20, 20. The photosensors 20, 20,... Are collectively covered with a protective insulating film 32 such as silicon nitride (Si ₃ N ₄ , SiN) or silicon oxide (SiO ₂ ).
Although FIG. 2 shows a matrix-like two-dimensional array of 8 rows × 8 columns, it may have more rows and columns.

  4 is a plan view showing the photosensor 20, and FIG. 5 is a cross-sectional view taken along the line V-V in FIG. As shown in FIGS. 4 and 5, the photosensor 20 includes a semiconductor film 23 that is a light receiving portion, a channel protective film 24 formed on the semiconductor film 23, and a bottom gate insulating film 22. The bottom gate electrode 21 formed below, the top gate electrode 31 formed on the semiconductor film 23 with the top gate insulating film 29 interposed therebetween, and the impurity semiconductor film 25 formed so as to overlap a part of the semiconductor film 23 An impurity semiconductor film 26 formed so as to overlap another part of the semiconductor film 23, a source electrode 27 overlapped with the impurity semiconductor film 25, and a drain electrode 28 overlapped with the impurity semiconductor film 26. 23 outputs an electric signal of a level according to the amount of light received.

  The bottom gate electrode 21 is formed on the insulating substrate 17 for each photosensor 20. Further, a plurality of bottom gate lines 41, 41,... Extending in the horizontal direction are formed on the insulating substrate 17, and each of the photosensors 20, 20,. These bottom gate electrodes 21 are formed integrally with a common bottom gate line 41. The bottom gate electrode 21 and the bottom gate line 41 have conductivity and light shielding properties, and are made of, for example, chromium, a chromium alloy, aluminum, an aluminum alloy, or an alloy thereof.

The bottom gate electrode 21 and the bottom gate lines 41, 41,... Of the photosensors 20, 20,. That is, the bottom gate insulating film 22 is a film formed in common to all the photosensors 20, 20,. The bottom gate insulating film 22 has insulating properties and light transmissive properties, and is made of, for example, silicon nitride (Si ₃ N ₄ , SiN) or silicon oxide (SiO ₄ ).

  A plurality of semiconductor films 23 are formed on the bottom gate insulating film 22 so as to be arranged in a matrix. The semiconductor film 23 is formed independently for each photosensor 20. In each photosensor 20, the semiconductor film 23 is disposed to face the bottom gate electrode 21, and the bottom gate insulating film 22 is sandwiched between the semiconductor film 23 and the bottom gate electrode 21. The semiconductor film 23 has a substantially rectangular shape in plan view, and is a layer formed of amorphous silicon or polysilicon that generates electron-hole pairs in an amount corresponding to the amount of received fluorescence.

  A channel protective film 24 is formed on the semiconductor film 23. The channel protective film 24 is patterned independently for each photosensor 20, and is formed on the central portion of the semiconductor film 23 in each photosensor 20. The channel protective film 24 has insulating properties and light transmissive properties, and is made of, for example, silicon nitride or silicon oxide. The channel protective film 24 protects the interface of the semiconductor film 23 from an etchant used for patterning. When light enters the semiconductor film 23, an amount of electron-hole pairs according to the amount of incident light is generated around the interface between the channel protective film 24 and the semiconductor film 23. In this case, holes are generated as carriers on the semiconductor film 23 side, and electrons are generated on the channel protective film 24 side.

An impurity semiconductor film 25 is partially formed on one end portion of the semiconductor film 23 so as to overlap the channel protection film 24, and an impurity semiconductor film 26 is partially formed on the other end portion of the semiconductor film 23. The channel protective film 24 is formed so as to overlap. The impurity semiconductor films 25 and 26 are patterned independently for each photosensor 20. The impurity semiconductor films 25 and 26 are made of amorphous silicon (n ⁺ silicon) containing n-type impurity ions.

  A source electrode 27 is formed on the impurity semiconductor film 25, and a drain electrode 28 is formed on the impurity semiconductor film 26. The source electrode 27 and the drain electrode 28 are formed for each photosensor 20. A plurality of source lines 42, 42,... And drain lines 43, 43,... Extending in the vertical direction are formed on the bottom gate insulating film 22. The source electrodes 27 of the photosensors 20, 20,... In the same row arranged in the vertical direction are formed integrally with the common source line 42, and the photosensors 20, 20 in the same row arranged in the vertical direction. ,... Are formed integrally with a common drain line 43. The source electrode 27, the drain electrode 28, the source line 42, and the drain line 43 have conductivity and light shielding properties, and are made of, for example, chromium, a chromium alloy, aluminum, an aluminum alloy, or an alloy thereof.

  The source electrode 27 and the drain electrode 28 and the source lines 42, 42,... And the drain lines 43, 43,. The top gate insulating film 29 is a film formed in common to all the photosensors 20, 20,. The top gate insulating film 29 has insulating properties and light transmissive properties, and is made of, for example, silicon nitride or silicon oxide.

  A top gate electrode 31 is formed for each photosensor 20 on the top gate insulating film 29. In each photosensor 20, the top gate electrode 31 is disposed to face the semiconductor film 23, and the top gate insulating film 29 and the channel protective film 24 are sandwiched between the top gate electrode 31 and the semiconductor film 23. Further, a plurality of top gate lines 44, 44,... Extending in the horizontal direction are formed on the top gate insulating film 29, and the photosensors 20, 20,. These top gate electrodes 31 are formed integrally with a common top gate line 44. The top gate electrode 31 and the top gate line 44 are conductive and light transmissive, for example, indium oxide, zinc oxide, tin oxide, or a mixture containing at least one of them (for example, tin-doped indium oxide ( ITO) and zinc-doped indium oxide).

  The top gate electrode 31 and the top gate lines 44, 44,... Of the photosensors 20, 20,... Are collectively covered with the protective insulating film 32, and the protective insulating film 32 is common to all the photosensors 20, 20,. It is a formed film. The protective insulating film 32 has insulating properties and light transmittance, and is made of silicon nitride or silicon oxide.

  An excitation light absorption layer 33 that absorbs excitation light of a phosphor 64 (shown in FIGS. 10 to 13) to be described later is provided on the upper surface of the protective insulating film 32. The excitation light absorbing layer 33 is preferably one that exhibits high transparency to the fluorescence emitted from the phosphor 64.

  A spot fixing layer 35 is provided on the upper surface of the excitation light absorbing layer 33. The spot fixing layer 35 fixes the spot 60 by covalent bonding or electrostatic coupling with a probe, which will be described later, which becomes the spot 60. The surface on which the spot fixing layer 35 is provided is a light receiving surface of the solid-state imaging device.

  The solid-state imaging device 10 configured as described above uses the surface of the spot fixing layer 35 as a light receiving surface, and is provided so as to convert the amount of light received by the semiconductor film 23 of each photosensor 20 into an electrical signal.

[3] Spot As shown in FIGS. 2 and 3, a spot is formed on the light receiving surface of the solid-state imaging device 10. Each spot 60 is formed by dropping a solution of cDNA (probe DNA 61) having a known base sequence serving as a probe or an antibody onto the spot fixing layer 35 and drying it. Hereinafter, a case where cDNA having a known base sequence is used as a probe will be described.

  In one spot 60, a crowd of a large number of single-stranded probe DNAs 61 having the same base sequence is immobilized on the light receiving surface of the solid-state imaging device 10, and the probe DNA 61 has a different base sequence for each spot 60. As the probe DNA 61, a DNA having a known mRNA base sequence or a DNA having the same or complementary base sequence as a part thereof is used. Specifically, for example, a cDNA library prepared from the same cell specimen as used in the fluorescently labeled DNA 62 described later can be used.

  One spot 60 is formed so as to overlap the photosensor 20. Note that the number of photosensors 20 that overlap one spot 60 may be different. In FIG. 1, 2 × 2 spots 60 are formed, but the number of spots 60 can be set to an arbitrary number according to the size of the solid-state imaging device 10.

[4] Partition Wall As shown in FIGS. 1 and 2, the partition wall 51 is in close contact with the spot fixing layer 35 along the edge of the solid-state imaging device 10. By providing the partition wall 51 in a frame shape, the inner part surrounded by the partition wall 51 becomes the well 52, and the light receiving surface of the solid-state imaging device 10 is exposed in the well 52, and a plurality of spots 60, 60,. Exist.

[5] Peltier element The Peltier element 12 is attached to a surface opposite to the light receiving surface of the solid-state imaging device 10. The Peltier element 12 heats or cools the solid-state imaging device 10. By heating or cooling the Peltier element 12, what is in the well 52 is also heated or cooled. As long as the inside of the well 52 can be heated and cooled, the position where the Peltier element 12 is provided may not be the opposite surface of the light receiving surface of the solid-state imaging device 10, and may be provided, for example, in the partition wall 51. Further, as long as heating and cooling can be performed electrically, the heating / cooling element may not be the Peltier element 12, and may be, for example, a combination of a heater and a cooler.

[7] Biopolymer Analysis Device Since the biopolymer analysis chip 1 is used by setting the biopolymer analysis chip 1 to the biopolymer analysis device 70, the biopolymer analysis device 70 will be described. FIG. 6 is a block diagram showing the configuration of the biopolymer analyzer 70, and FIG. 7 is a circuit diagram showing the set biopolymer analysis chip 1 and its peripheral circuits.

  As shown in FIGS. 6 and 7, the biopolymer analyzer 70 includes a detachable biopolymer analysis chip 1 and a top gate driver 74 that drives the solid-state imaging device 10 of the attached biopolymer analysis chip 1. The bottom gate driver 75, the drain driver 76, the controller 71 that controls these, the output device 72 that outputs (displays or prints) the signal output from the controller 71, and the excitation light ( An excitation light irradiation device 73 that irradiates the biopolymer analysis chip 1 mainly with ultraviolet rays.

  The top gate driver 74 is connected to the top gate lines 44, 44,..., And the bottom gate driver 75 is connected to the bottom gate lines 41, 41,. The drain driver 76 includes a column switch 81, a precharge switch 82, and an amplifier 83. The column switch 81 is connected to the drain lines 43, 43,.

  The solid-state imaging device 10 is detachably provided to the top gate driver 74, the bottom gate driver 75, and the drain driver 76. When the solid-state imaging device 10 is attached to the top gate driver 74, the bottom gate driver 75, and the drain driver 76, the source lines 42, 42,... Are connected to the constant voltage source Vss, specifically, the source lines 42, 42,. Are connected to the ground of ± 0 [V].

  The top gate driver 74, the bottom gate driver 75, and the drain driver 76 are controlled by the controller 71. Here, FIG. 8 is a timing chart of signals output from the top gate driver 74, the bottom gate driver 75, and the controller 71.

  As shown in FIGS. 6 to 8, the controller 71 outputs a control signal φchm, a control signal φtg, and a control signal φbg. The control signal φchm is a signal output from the controller 71 to the top gate driver 74 and the bottom gate driver 75, the control signal φtg is a signal output from the controller 71 to the top gate driver 74, and the control signal φbg is The control signal φpg is a signal output from the controller 71 to the bottom gate driver 75, and the control signal φpg is a signal output from the controller 71 to the precharge switch 82 of the drain driver 76.

  A control signal φchm output from the controller 71 is a gate signal. That is, the controller 71 outputs the control signal φchm to the top gate driver 74 and the bottom gate driver 75, thereby operating the top gate driver 74 and the bottom gate driver 75 in either the target movement mode M1 or the sensor detection mode M2. Specifically, when the control signal φchm is at a high level, the top gate driver 74 and the bottom gate driver 75 operate in the target movement mode M1, and when the control signal φchm is at a low level, the top gate driver 74 and the bottom gate driver 75 are operated. Operates in the sensor detection mode M2.

  The controller 71 operates the top gate driver 74 by outputting a control signal φtg to the top gate driver 74. Further, the controller 71 operates the bottom gate driver 75 by outputting a control signal φbg to the bottom gate driver 75.

  7 and 8, signals φT1 to φTn are signals output to the top gate lines 44 by the top gate driver 74. Numbers 1 to n attached to the signals φT1 to φTn represent row numbers of the top gate lines 44. That is, for example, the output voltage to the top gate line 44 in the first row is the signal φT1, and the output voltage to the top gate line 44 in the second row is the signal φT2. The signals φB1 to φBn are signals output to the bottom gate lines 41 by the bottom gate driver 75. Numbers 1 to n attached to the signals φB1 to φBn represent row numbers of the bottom gate line 41. Further, as shown in FIG. 2, when the total number of rows is 8, n = 8. Each signal shown in FIGS. 7 and 8 is represented by a voltage level.

  The top gate driver 74 operates according to the control signal φchm and the control signal φtg. Here, when the control signal φchm is at a high level, that is, in the target movement mode M1, the top gate driver 74 uses at least one of the top gate lines 44, 44,... According to the control signal φtg (in FIG. A state in which a low level constant voltage (-15 V in FIG. 8) is applied to the first row, the fourth row, and the fifth row is maintained. In the target movement mode M1, the top gate driver 74 applies a voltage higher than the low level (second line) to the other top gate lines 44 (second and third rows in FIG. 8) according to the control signal φtg. Voltage) is applied to change the voltage level.

  On the other hand, when the control signal φchm is at a low level, that is, in the sensor detection mode M2, the top gate driver 74 follows the control signal φtg to a high level pulse voltage (first voltage) exceeding ± 0 [V] (FIG. 8 is +15 [V] as an example.) Are sequentially applied to the top gate lines 44, 44,. When the top gate driver 74 does not apply a pulse voltage, that is, when the signals φT1 to φTn are at a low level, a negative voltage (as an example, −15 [V] in FIG. 8) is applied by the top gate driver 74 to the top gate line. 44, 44,...

  The bottom gate driver 75 operates according to the control signal φchm and the control signal φbg. Here, when the control signal φchm is at a high level, that is, in the target movement mode M1, the bottom gate driver 75 does not apply a voltage to any of the bottom gate lines 41, 41,. Is also at a low level (± 0 [V] in FIG. 8).

  On the other hand, when the control signal φchm is at a low level, that is, in the sensor detection mode M2, the bottom gate driver 75 follows the control signal φbg to generate a high level pulse voltage (third voltage) (in FIG. 8, as an example +15 [V Are sequentially applied to the bottom gate lines 41, 41,. When the bottom gate driver 75 does not apply a pulse voltage, that is, when the signals φB1 to φBn are at a low level, the voltages of the bottom gate lines 41, 41,... Are ± 0 [V].

  The timing of the pulse voltage applied by the top gate driver 74 and the bottom gate driver 75 in the sensor detection mode M2 will be described with reference to FIGS. Here, FIG. 9 shows that in the sensor detection mode M2, the top gate driver 74 applies a high-level pulse voltage to the top gate line 44 in the i-th row, and then the bottom gate driver 75 applies the bottom gate in the (i + 1) -th row. 4 is a timing chart of signals output by a top gate driver 74, a bottom gate driver 75, and a drain driver 76 until a high level read pulse is applied to a line 41; Note that i is an arbitrary number from 1 to n. When the i-th row is the last row, the (i + 1) -th row is the first row.

  As shown in FIGS. 8 and 9, the bottom gate driver 75 applies the bottom gate line 41 of the same row after a predetermined time after the top gate driver 74 applies a high-level pulse voltage to the top gate line 44 of any row. The top gate driver 74 and the bottom gate driver 75 shift the output signal so that a high level pulse voltage is applied to the output signal. That is, in the same row, the timing at which the pulse voltage is applied to the bottom gate line 41 is delayed from the timing at which the pulse voltage is applied to the top gate line 44.

  In FIG. 9, the reset time Treset is the time during which the pulse voltage is applied to the top gate line 44, the read time Tread is the time during which the pulse voltage is applied to the bottom gate line 41, and the storage time Te is The time from when the application of the pulse voltage to the top gate line 44 is stopped to when the application of the pulse voltage to the bottom gate line 41 is started.

  As shown in FIG. 9, the control signal φpg is an amplitude signal that becomes a high level during the storage time Te of any row in the sensor detection mode M2. When the control signal φpg becomes high level, the precharge switch 82 is turned on, and the precharge voltage Vpg is applied to all the drain lines 43, 43,. When the control signal φpg is at a low level, the precharge switch 82 is off, so that the precharge voltage Vpg is not applied to any of the drain lines 43, 43,. In FIG. 9, a precharge time Tprch is a time during which the control signal φpg is at a high level.

  The column switch 81 outputs the voltages of the drain lines 43, 43,... To the amplifier 83 in the column order after the application of the precharge voltage Vpg. The voltage amplified by the amplifier is converted into a digital image signal by the A / D converter 78, and the A / D converted image signal is input to the controller 71.

The controller 71 has a function of turning on the excitation light irradiation device 73. The excitation light irradiation device 73 irradiates the biopolymer analysis chip 1 with excitation light that excites a phosphor to be described later.
The controller 71 has a function of causing the output device 72 to output an image according to the input two-dimensional image data. The output device 72 is a plotter, a printer, or a display.
When the controller 71 controls the Peltier element 12, the Peltier element 12 is heated or cooled, or heating or cooling of the Peltier element 12 is stopped.

[8] Biopolymer Analysis Method, Biopolymer Analysis Chip Control Method, and Analytical Device Operation Next, a method for analyzing a sample using the biopolymer analyzer 70 will be described.

  As a sample to be analyzed by the biopolymer analysis chip 1, DNA can be used. As a sample DNA, mRNA obtained by extracting mRNA expressed in a cell sample and performing RT-PCR reaction using reverse transcriptase can be used. The cDNA is labeled with a fluorophore. As the phosphor, one that is excited by excitation light emitted from the excitation light irradiation device of the analyzer and emits fluorescence by the excitation light is selected. As the phosphor, for example, CyDye Cy2 (Amersham) Made).

  In order to label cDNA with a phosphor, for example, an RT-PCR reaction may be performed using an oligo dT primer labeled with a phosphor or a labeled dNTP mix. Hereinafter, this labeled cDNA is referred to as fluorescently labeled DNA.

  Next, the biopolymer analysis chip 1 is set, the solid-state imaging device 10 is connected to the top gate driver 74, the bottom gate driver 75, and the drain driver 76, the Peltier element 12 is connected to the controller 71, and the excitation light irradiation device 73 is connected. Is opposed to the light receiving surface of the solid-state imaging device 10.

Next, as illustrated in FIG. 10, the controller 71 causes the Peltier element 12 to generate heat, and the solid-state imaging device 10 is heated by the Peltier element 12.
In this heated state, the operator injects a solution containing the fluorescently labeled DNA 62 labeled with the phosphor 64 (hereinafter referred to as a fluorescently labeled DNA solution) into the well 52. The fluorescently labeled DNA solution injected into the well 52 is preferably heated to about 75 ° C. by the Peltier element 12. When the fluorescently labeled DNA solution is heated above room temperature, the fluorescently labeled DNA 62 and the probe DNA 61 become single stranded.

  Next, the controller 71 outputs the control signal φchm to the top gate driver 74 and the bottom gate driver 75, and the control signal φchm becomes high level. Then, the top gate driver 74 and the bottom gate driver 75 operate in the target movement mode M1. That is, as shown in FIG. 8, while the control signal φchm is at a high level, the top gate driver 74 applies a positive voltage to at least one of the top gate lines 44, 44,. , Change its voltage level.

  The movement of the fluorescently labeled DNA 62 in the target movement mode M1 will be described with reference to the schematic diagrams of FIGS. As shown in FIG. 10, when a positive voltage is not applied to the top gate lines 44, 44,..., The fluorescently labeled DNA 62 is floating in the solution on the light receiving surface of the solid-state imaging device 10. After that, as shown in FIG. 11, the control signal φchm becomes a high level, and the fluorescently labeled DNA 62 charged with a negative charge is attracted to the row of the top gate lines 44, 44,. The There is a spot 60 in a row to which a positive voltage is applied, and the concentration of the fluorescently labeled DNA 62 is concentrated around the spot 60. Therefore, the fluorescently labeled DNA 62 is easily hybridized to the probe DNA 61 of the spot 60 in a short time.

  Further, when the controller 71 outputs the high-level control signal φchm, that is, during the target movement mode M1, the controller 71 changes the voltage polarity of the Peltier element 12 to cause the Peltier element 12 to absorb heat. Thereby, the solid-state imaging device 10 and the fluorescence labeled DNA solution are cooled. It is preferable that the fluorescently labeled DNA solution injected into the well 52 is cooled to about 25 ° C. by the Peltier element 12. When the fluorescently labeled DNA solution is cooled to room temperature, it becomes easy to hybridize and becomes double-stranded on the electrode.

  As described above, when the fluorescently labeled DNA 62 is concentrated in the spot 60 and the fluorescently labeled DNA solution is cooled, if the fluorescently labeled DNA 62 is complementary to the probe DNA 61 of the spot 60, the fluorescently labeled DNA 62 is attached to the probe DNA 61. Hybridization improves the efficiency of hybridization. On the other hand, the fluorescently labeled DNA 62 that is not complementary to the probe DNA 61 does not bind to the spot 60.

  In addition, since the positive voltage applied to the top gate line 44 can be arbitrarily set during the target movement mode M1, electric contact of the top gate line 44 can be suppressed. That is, if a positive high voltage having a difference of +30 V or more between the low level and the high level is continuously applied to the top gate line 44, the fluorescently labeled DNA solution or the like existing on the surface passes through the through hole of the protective insulating film 32. There is a possibility that the top gate line 44 may come into contact with the line 44, but in this embodiment, the positive voltage of the top gate line 44 is variable in a range where the potential difference between the low level and the high level is less than + 30V. By setting as described above, electric contact of the top gate line 44 can be suppressed. In particular, the positive voltage of the top gate line 44 is preferably set to 1 V or more and 3 V or less (the potential difference from the low level is +16 V or more and +18 V or less). Further, by performing stepwise without increasing or decreasing the voltage, electric contact can be suppressed without hindering movement of the target. For example, in this embodiment, the first stage is set to -1.5V, and the second stage is set to 1.5V.

  Next, the controller 71 sets the control signal φchm to a low level to stop the application of the positive voltage to the top gate line 44 and to cause the Peltier element 12 to generate heat. As a result, as shown in FIG. 12, the fluorescence-labeled DNA 62 not bound to the probe DNA 61 floats in the solution. At this time, the fluorescently labeled DNA solution injected into the well 52 is preferably heated to the dissociation temperature of the probe DNA 61 by the Peltier element 12. The dissociation temperature of the probe DNA 61 here means that the double strand that is mishybridized and unstable is cut into single strand, and the double strand that is correctly hybridized and stable is double. The temperature at which the chain can remain. The dissociation temperature is specific to the DNA base sequence, but is in the range of 25 ° C. or higher and lower than 75 ° C., and can be arbitrarily set depending on the DNA base sequence to be identified.

  As described above, when the control signal φchm is set to the low level to stop applying the positive voltage to the top gate line 44 and the fluorescently labeled DNA 62 is heated to the dissociation temperature, the DNA other than the one that has formed a normal double strand is used as an electrode. It can be separated from the surroundings and moved.

  Thereafter, the fluorescently labeled DNA solution in the well 52 is washed away with a washing buffer solution, and the fluorescently labeled DNA 62 that has not hybridized with the probe DNA 61 is removed from the well 52. On the other hand, the fluorescently labeled DNA 62 hybridized with the probe DNA 61 remains in the well 52 while being bound to the probe DNA 61.

  Thereafter, when the controller 71 controls the excitation light irradiation device 73 to turn on the excitation light irradiation device 73, excitation light is emitted from the excitation light irradiation device 73 toward the light receiving surface of the solid-state imaging device 10.

  Among the spots 60, 60,..., Fluorescence (mainly in the visible light wavelength region) is emitted from the spot 60 hybridized with the fluorescently labeled DNA 62, and no fluorescence is emitted from the spot 60 that is not bound to the fluorescently labeled DNA 62. Therefore, high-intensity fluorescence is incident on the photosensor 20 corresponding to the spot 60 bonded to the fluorescently labeled DNA 62, and almost no fluorescence is incident on the photosensor 20 corresponding to the spot 60 not bonded to the fluorescently labeled DNA 62. Further, the fluorescence does not enter the photosensor 20 that does not correspond to the spot 60. Because the spots 60, 60,... Are fixed on the light receiving surface of the solid-state imaging device 10, the fluorescence emitted from the spot 60 combined with the fluorescently labeled DNA 62 is not attenuated so much and is applied to the photosensor 20 corresponding to the spot 60. Incident light generates electron-hole pairs. Therefore, even if the sensitivity of the photosensor 20 is low, the intensity can be sufficiently detected.

  The controller 71 outputs the control signal φtg, the control signal φbg, and the control signal φpg to the top gate driver 74, the bottom gate driver 75, and the drain driver 76 in a state where the excitation light irradiation device 73 is turned on. The bottom gate driver 75 and the drain driver 76 drive the solid-state imaging device 10. At this time, since the control signal φchm is at a low level, the sensor detection mode M2 is set.

  In the sensor detection mode M2, as shown in FIG. 8, the top gate driver 74 applies a pulse voltage to the top gate lines 44, 44,... Sequentially from the top gate line 44 of the first row. Further, the bottom gate driver 75 applies a pulse voltage to the bottom gate lines 41, 41, 41,... Sequentially from the bottom gate line 41 of the first row.

  During the precharge time Tprch of each row, the control signal φpg input to the precharge switch 82 of the drain driver 76 is at a high level, so that the precharge voltage Vpg is all drained during the precharge time Tprch of each row. Applied to the lines 43, 43,.

  The operation of each i-th photo sensor 20 will be described in detail. As shown in FIG. 9, the top gate driver 74 applies a pulse voltage to the i-th top gate line 44. In the reset time Treset of the i-th row, carriers (here, holes) accumulated in the semiconductor film 23 of each photosensor 20 in the i-th row and in the vicinity of the interface between the semiconductor film 23 and the channel protective film 24. ) Is repelled and discharged by the voltage of the top gate electrode 31.

  In the storage time Te from the end of the application of the pulse voltage to the i-th top gate line 44 to the application of the pulse voltage to the i-th bottom gate line 41, an amount according to the amount of incident light. Electron-hole pairs are generated in the semiconductor film 23, of which holes are accumulated in the semiconductor film 23 or in the vicinity of the interface between the semiconductor film 23 and the channel protective film 24 by the electric field of the top gate electrode 31.

  Next, during the precharge time Tprch in the second half of the storage time Te, the drain driver 76 applies the precharge voltage Vpg to all the drain lines 43, 43,. In the precharge time Tprch, the voltage of the top gate electrode 31 of each photosensor 20 in the i-th row is a negative voltage (−15 [V]), and the voltage of the bottom gate electrode 21 is ± 0 [V]. The channel between the semiconductor film 23 and the drain electrode 28 is not formed because the gate-source voltage is low only by the charge of the holes accumulated in the semiconductor film 23 or in the vicinity of the interface between the semiconductor film 23 and the channel protective film 24. No current flows between the source electrode 27. Since no current flows between the drain electrode 28 and the source electrode 27 during the precharge time Tprch, the drain electrode 28 of each photosensor 20 in the i-th row is applied by the precharge voltage Vpg applied to the drain lines 43, 43,. Is charged.

  Next, the application of the precharge voltage Vpg by the drain driver 76 is finished, and the bottom gate driver 75 applies a pulse voltage to the bottom gate line 41 of the i-th row. In the read time Tread in which the bottom gate driver 75 applies a pulse voltage to the i-th bottom gate line 41, the voltage of the bottom gate electrode 21 of each photosensor 20 in the i-th row is a positive voltage (+10 [V]). Therefore, each photosensor 20 in the i-th row is turned on.

  In the read time Tread, the carriers accumulated in the storage time Te work so as to alleviate the negative electric field of the top gate electrode 31, so that an n channel is formed in the semiconductor film 23 by the positive electric field of the bottom gate electrode 21, and the drain A current accompanying the action of carriers flows from the electrode 28 to the source electrode 27. Therefore, at the read time Tread, the voltages of the drain lines 43, 43,... Tend to gradually decrease with time due to the drain-source current.

  Here, as the amount of light incident on the semiconductor film 23 increases during the storage time Te, the number of carriers that are generated and accumulated according to the amount of light incident on the semiconductor film 23 increases, and as the number of accumulated carriers increases, the readout time increases. In Tread, the current flowing from the drain electrode 28 to the source electrode 27 also increases. Therefore, the change tendency of the voltage of the drain lines 43, 43,... During the read time Tread depends on the amount of light incident on the semiconductor film 23 during the storage time Te. That is, as the amount of light incident on the semiconductor film 23 increases during the storage time Te, the voltage change rate of the drain lines 43, 43,. Therefore, the drain line 43, 43 after the elapse of a predetermined time from the start of the column switch 81 and the read time Tread between the read time Tread of the i-th row and the precharge time Tprch of the next (i + 1) -th row. ,... Are sequentially output to the amplifier 83 by the column switch 81, amplified by the amplifier 83, and further A / D converted by the A / D converter 78. Thereby, it converts into the intensity | strength of light. Note that the time until the predetermined threshold voltage is reached may be detected via the column switch 81 between the read time Tread of the i-th row and the precharge time Tprch of the next (i + 1) -th row. Even in this case, the light intensity is converted.

  The above-described series of image reading operations is set as one cycle, and the same processing procedure is repeated for each photosensor 20 in all rows, so that the solid-state imaging device 10 detects the light amount by each of the photosensors 20, 20,. The light intensity distribution along the light receiving surface is acquired as a two-dimensional image. The controller 71 inputs an image acquired by the solid-state imaging device 10 and outputs the image to the output device 72. And the process of the controller 71 is complete | finished.

  The operator confirms the presence or absence of hybridization from the image output by the output device 72, and if hybridization has occurred, specifies the base sequence of the fluorescently labeled DNA. That is, since the base sequence of the fluorescence-labeled DNA is a sequence complementary to the spot 60 that overlaps the pixel that emitted fluorescence by hybridization in the image, which part of the output image data emitted fluorescence. Thus, the base sequence of the fluorescently labeled DNA can be specified.

  As described above, according to the present embodiment, in the target movement mode M1, the fluorescently labeled DNA is applied to each spot 60 on the surface of the solid-state imaging device 10 only by applying a positive voltage to the top gate lines 44, 44,. Since it moves and concentrates, it is not necessary to separately provide the solid-state imaging device 10 with an electrode for moving the fluorescently labeled DNA.

  Further, since the spots 60, 60,... Are scattered on the light receiving surface of the solid-state imaging device 10, a two-dimensional image can be obtained simply by imaging with the solid-state imaging device 10. Furthermore, since a clear image can be obtained by the solid-state imaging device 10 without providing a lens in the biopolymer analyzer 70, the biopolymer analyzer 70 can have a simple structure. Furthermore, since the light emitted from the spot 60 is incident on the light receiving surface of the solid-state imaging device 10 without being attenuated, the sensitivity of the solid-state imaging device 10 may not be high.

<Modification 1>
As shown in FIG. 14, electrodes 151 and 152 may be provided in opposing portions of the partition wall 51, and the electrodes 151 and 152 may be opposed to each other. In this case, in the target movement mode M1, when the voltage of the electrode 151 is made higher than the voltage of the electrode 152 and an electric field is generated in the fluorescently labeled DNA solution, the fluorescently labeled DNA 62 in the fluorescently labeled DNA solution migrates toward the electrode 152. To do.

<Modification 2>
As shown in FIG. 15, an auxiliary electrode 153 may be provided so as to face the light receiving surface of the solid-state imaging device 10. In this case, the fluorescently labeled DNA 62 can be moved at higher speed without imposing restrictions on the applied voltage value and voltage application time for sensor detection. For example, the fluorescence-labeled DNA 62 can be moved also in the sensor detection mode M2 by applying a voltage to the auxiliary electrode 153 in the sensor detection mode M2.

<Modification 3>
As shown in FIG. 16, a plurality of auxiliary electrodes 154 orthogonal to the top gate line 44 in plan view may be provided between the protective insulating film 32 and the excitation light absorbing layer 33. By selectively applying a positive voltage to these auxiliary electrodes 154 in the target movement mode M1, the fluorescently labeled DNA 62 can be moved both in the direction of the top gate line 44 and in the direction perpendicular to the top gate line 44. .

<Modification 4>
The spot 60 is composed of the probe DNA 61, but may be composed of a probe antibody. As the probe antibody, an antibody that binds to an antigen such as a known protein or sugar chain to be detected (hereinafter referred to as a probe antibody), for example, a monoclonal antibody can be used.
As the probe of the spot 60, other known biopolymers or low molecules may be used. For example, a peptide or protein serving as an antigen, a sugar chain, a low molecular ligand, a known cell, or the like may be used.

FIG. 1 is a perspective view showing a biopolymer analysis chip used in a biopolymer analyzer according to an embodiment of the present invention. FIG. 2 is a plan view showing the biopolymer analysis chip. FIG. 3 is a schematic cross-sectional view of the surface along III-III. FIG. 4 is a plan view showing a one-pixel photoelectric conversion element in the biopolymer analysis chip. 5 is a cross-sectional view taken along the line V-V in FIG. FIG. 6 is a block diagram showing a configuration of a biopolymer analyzer using the biopolymer analysis chip. FIG. 7 shows the biopolymer analysis chip and its peripheral circuits. FIG. 8 is a timing chart of signal transition for driving the biopolymer analysis chip. FIG. 9 is a timing chart showing the transition of the signal voltage in a certain row. FIG. 10 is an explanatory diagram of a method for hybridizing fluorescently labeled DNA and probe DNA. FIG. 11 is an explanatory diagram of a method for hybridizing fluorescently labeled DNA and probe DNA. FIG. 12 is an explanatory diagram of a method for hybridizing fluorescently labeled DNA and probe DNA. FIG. 13 is an explanatory diagram in a state in which the biopolymer analysis chip is irradiated with excitation light. FIG. 14 is a cross-sectional view showing a biopolymer analysis chip in a modified example. FIG. 15 is a cross-sectional view showing a biopolymer analysis chip in a modified example. FIG. 16 is a cross-sectional view showing a biopolymer analysis chip in a modified example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Solid-state imaging device 12 Peltier device 17 Insulating substrate 23 Semiconductor film 32 Protective insulating film 41 Bottom gate line 44 Top gate line 60 Spot 70 Biopolymer analyzer 74 Top gate driver 75 Bottom gate driver

Claims (5)

In a solid-state imaging device comprising a semiconductor film, a photosensor having a light-transmissive first gate electrode,
In the sensor detection mode, the first gate electrode is applied with a first voltage in order to accumulate carriers generated according to the amount of light incident on the semiconductor film,
In the target movement mode, the potential changes within a range where the potential difference is less than +30 V with respect to the first voltage and a positive second voltage is applied to attract the biopolymer charged with a negative charge.
A biopolymer analyzer characterized by the above. The photosensor includes a second gate electrode,
In the sensor detection mode, after applying the first voltage to the first gate electrode, a third voltage is applied to the second gate electrode in order to flow a current accompanying the action of the carrier after a predetermined time. The biopolymer analyzer according to claim 1. A heating / cooling element for heating / cooling the solid-state imaging device;
Before the second voltage is applied to the first gate electrode, the heating and cooling element heats the solid-state imaging device,
When the second voltage is applied to the first gate electrode, the heating and cooling element cools the solid-state imaging device,
The biopolymer analyzer according to claim 1 or 2, wherein the heating / cooling element heats the solid-state imaging device after the second voltage is applied to the first gate electrode.   After the second voltage is applied to the first gate electrode, the temperature at which the heating / cooling element heats the solid-state imaging device is a biopolymer mishybridized with the probe fixed on the light receiving surface of the spot. The biopolymer analyzer according to any one of claims 1 to 3, wherein the biopolymer analyzer is a dissociation temperature for dissociating. In a solid-state imaging device comprising a semiconductor film, a photosensor having a light-transmissive first gate electrode,
In the sensor detection mode, a first voltage is applied to the first gate electrode in order to accumulate carriers generated according to the amount of light incident on the semiconductor film,
In the target movement mode, the potential changes within a range where the potential difference is less than +30 V with respect to the first voltage in order to attract the biopolymer charged with a negative charge , and a positive second voltage is applied.
A biopolymer analysis method characterized by the above.

Images