JPH11248680A - Electrophoresis and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an isoelectric point electrophoresis easily and accurately pesfrmable in a short time. SOLUTION: Is this electrophoresis, a gel 33 after electrophoresis is broughrt into contact with a pH sensor 24 for an optically scanning two-dimensional pH distribution measuring device 1 to directly measure pH at points of the gel 33. The measurement results are recorded, an object to be measured contained in the gel 33 is dyed with a proper method and the position of a band obtained by dying is confirmed in a visible or optical manner and is collated to the pH obtained by the pH measurement to find the pH of the object to be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an electrophoresis method and an apparatus therefor.

[0002]

2. Description of the Related Art Isoelectric focusing is used for analyzing proteins and the like. For the isoelectric focusing, a gel such as acrylamide or agar containing a component that forms a pH gradient by electrophoresis is used. And
When a protein to be measured is included in the gel and subjected to electrophoresis, the gel moves to a specific location in the pH gradient and stops depending on the properties of the protein. Then, where the protein stopped, as an index of its properties, for example, p
A qualitative analysis can be performed, such as I = 8.6.

[0003]

However, the above-mentioned generally performed isoelectric focusing has the following problems. That is, the gradient of the pH formed in the gel may vary depending on the lot of the gel and the like. For this reason, it is necessary to calibrate the pH gradient for each lot of gel using a protein with a known pI as a marker. In addition, each time an experimenter performs an electrophoresis with an appropriate marker together with the sample, it is necessary to determine the pI of the measurement target from the band position of the marker. The above-mentioned calibration work itself is an unnecessary experiment work, and the marker for pI itself is a special protein, which is expensive and has a short storage period. The band formed by the pI marker is not always linear, but has a distorted shape depending on the electrophoresis conditions.
For this reason, it may be difficult to accurately check the pI. Furthermore, in order to improve the accuracy of the pH value comparison in the gel using the pI marker, it is necessary to increase the size of the electrophoresis gel to some extent. However, as the gel size increases, the time required to migrate the sample increases, and either the collation accuracy or the migration time must be sacrificed.

On the other hand, it is conceivable that the pH distribution of the gel is directly measured by a glass electrode method. However, even if the pH gradient is as steep as about 1 pH / cm, and the glass electrode having a special shape is directly measured, It is impossible to do.

There is also a method in which the gel is cut into strips in the direction orthogonal to the pH gradient (divided into fractions), and the components of each fraction are extracted and the pH is measured using a glass electrode or the like, but the procedure is complicated. In addition, there is a drawback that errors are likely to occur due to measurement in many steps.

Recently, research and development of an apparatus for two-dimensionally measuring the concentration of a substance (such as ions) dissolved in a liquid or a liquid impregnated in the substance have been carried out.
One of the methods for measuring the two-dimensional distribution is LAPS.
(Light-Addressable Potent
There is an electrochemical image measurement device including an iometric sensor. Such a device, for example,
Jpn. J. Appl. Phys. Vol. 33 (19
94) As described in pp L394-L397, a semiconductor substrate having a sensor surface responsive to ions and the like is scanned with an appropriate light, and the AC scanning induced in the semiconductor substrate by the optical scanning is performed. The measurement can be performed by taking it out.

[0007] The concentration distribution of the dissolved substance is measured by directly inserting or contacting the sensor section of the apparatus with the target substance to be measured. The obtained data is output as a two-dimensional or three-dimensional density distribution image by computer processing. Not only the concentration distribution at a certain time but also the state of the change can be tracked in real time. An image obtained in real time can be easily compared with an optical image obtained by visual observation, a CCD camera, or the like.

The applicant of the present application has filed an invention on the above-mentioned optical scanning type two-dimensional density distribution measuring apparatus and a technique related thereto with Japanese Patent Application No. Hei 7-39114 (Japanese Unexamined Patent Application Publication No.
213580).

However, the above-mentioned conventional optical scanning type two-dimensional concentration distribution measuring device measures the ion concentration such as pH, and is not used for electrophoresis.

The present invention has been made in consideration of the above-mentioned matters, and has as its object to provide an electrophoresis method and an apparatus thereof which can perform isoelectric focusing easily, accurately and in a short time. .

[0011]

Means for Solving the Problems In order to achieve the above object, in the electrophoresis method of the present invention, the gel after electrophoresis is brought into contact with a pH sensor of an optical scanning type two-dimensional pH distribution measuring device, The pH value at each point of the gel was directly measured, the measurement result was recorded, and then the measurement target contained in the gel was stained by an appropriate method, and the position of the band obtained by this staining was visually or The pI of the object to be measured is determined by confirming with an optical method and comparing the position of the band with the pH value obtained by the pH measurement (claim 1).

An electrophoresis apparatus according to the present invention comprises an optical scanning type two-dimensional pH distribution measuring apparatus having a planar pH sensor on which a gel is placed, a power supply for electrophoresing the gel, and an electrophoresis apparatus. And a solution tank containing a solution for immersing these electrodes (claim 2).

[0013]

Embodiments of the present invention will be described with reference to the drawings. 1 to 5 show a first embodiment of the present invention. FIGS. 1 and 2 schematically show the structure of the apparatus, and are not strict structural diagrams.
Some parts do not match.

First, in FIGS. 1 to 3, reference numeral 1 denotes an optical scanning type two-dimensional pH distribution measuring device main body (hereinafter, simply referred to as a measuring device main body), and a gel cassette 2 and the gel cassette 2 are placed horizontally. And a two-dimensional scanning device 3 for scanning in two-dimensional directions (the directions of arrows X and Y in FIG. 1). Reference numeral 4 denotes a light source for irradiating a pH sensor (to be described later) incorporated in the gel cassette 2 with, for example, a laser beam 5 in a near-infrared region. Reference numeral 7 denotes a contact probe unit for connecting between the control box 6 and the ohmic electrode 8, the counter electrode 9, and the reference electrode 10 (all described later) provided on the measuring apparatus main body 1.

Numerals 11 and 12 denote an electrophoretic anode tank and a cathode tank set above the gel cassette 2, respectively.
Is a power supply for electrophoresis. Reference numeral 14 denotes a cover body that detachably covers the upper surface of the gel cassette 2, and reference numeral 15 denotes an optical image observation device such as a CCD camera provided above the gel cassette 2.

Reference numeral 16 denotes a control / image processing apparatus which controls the entire electrophoresis apparatus, processes signals sent from the measuring apparatus main body 1, the CCD camera 15, and the like, and displays and records the results. It is a computer having an image processing function. The computer 16 has a function of performing processes such as control and various calculations, and includes an input device 17 such as an input keyboard, a display device 18 such as a color display, and a memory device 19.

Next, the structure of each member denoted by reference numerals 2 to 14 will be described in detail. First, the gel cassette 2 will be described with reference to FIG. In this figure, reference numeral 20 denotes a cartridge base, which is made of an appropriate resin, and has a rectangular shape in a plan view having a spot facing surface 21 for holding a pH sensor 24 to be described later on the upper surface side in the center thereof so as not to shift. A through hole 22 is provided. Reference numeral 23 denotes a hole for locking and fixing the anode cell 11 and the cathode cell 12, respectively.

Reference numeral 24 denotes a pH sensor which is removably incorporated into the cartridge base 20 and has a rectangular shape in plan view, and is formed so that its outer shape substantially matches the shape and dimensions of the spot facing surface 21. As shown in FIG. 3, the pH sensor 24 is formed by thermally oxidizing a SiO ₂ layer 26 on a top surface of a semiconductor substrate 25 made of silicon or the like having a small thickness (for example, 100 μm or less) and a Si ₃ N ₄ layer 27 as a sensor surface. It is formed sequentially by a method such as CVD, is formed so as to respond to hydrogen ions, and the size of the sensor surface 27 is, for example, 2.0 cm square.

An ohmic electrode 8 for extracting a current signal is provided so as to be in contact with the lower surface of the semiconductor substrate 25 of the pH sensor 24. The ohmic electrode 8 has an electrode body 28 whose outer shape is countersunk. It has a hole 29 which substantially matches the shape and dimensions of the surface 21 and the center matches the shape and dimensions of the through-hole 22, and has an appropriately bent contact portion 30 at an appropriate location around the hole 29. The ohmic electrode 8 is made of a metal plate of silver or platinum having an appropriate thickness. The contact surface 30a of the contact portion 30 is plated with, for example, gold to prevent oxidation and reduce contact resistance. It is configured.

Reference numeral 31 denotes a packing for sealing, which is formed so that its outer shape substantially matches the ohmic electrode body 8, and has a hole 32 in the center which matches the shape and dimensions of the through holes 22, 29.
have. This packing 31 is made of, for example, silicon rubber.

The pH sensor 24, the ohmic electrode 8 and the packing 31 are composed of the packing 31, the ohmic electrode 8
And a pH sensor 24 on the spot face 21 of the cartridge base 20 in this order. In this case, the pH sensor 24
Is set so that the sensor surface 27 is flush with the upper surface of the cartridge base 20.

Reference numeral 33 denotes a gel for migration of a sample such as a protein, which is made of, for example, polyacrylamide gel, and has a comb-shaped sample injection recess 34 for injecting a sample at one end thereof. × 3.5
It is formed in a size of cm × 2.0 mm (thickness).

Reference numeral 35 denotes a transparent cartridge cover for covering the polyacrylamide gel 33, which is made of a suitable resin, and has a slightly large opening 36 formed substantially in the center thereof.
Rectangular openings 37 and 38 for injecting an anode buffer solution and a cathode buffer solution described later are formed on both sides thereof.

As described above, the gel cassette 2 is constituted, for example, as a disposable unit by members represented by reference numerals 20, 24, 8, 31, 33, and 35.

A two-dimensional scanning device 3 for scanning the gel cassette 2 having the above-described structure in two-dimensional directions is not shown in detail in FIGS. And is configured to be able to irradiate the laser beam 5, and is controlled by the scanning control device 39.

A light source 4 for irradiating the pH sensor 24 of the gel cassette 2 mounted on the two-dimensional scanning device 3 with a laser beam 5 is provided below the two-dimensional scanning device 3 and is controlled by a light source control device 40. The semiconductor substrate 2 of the sensor 24 that is controlled and scanned in the two-dimensional direction by the two-dimensional scanning device 3
The laser beam 5 adjusted to have an optimum beam diameter with respect to the laser beam 5 is emitted at a constant cycle.

Next, the structure of the control box 6 will be described with reference to FIG. 1 and FIG. 2. The control box 6 includes an ohmic electrode 8, a counter electrode 9, and a comparative electrode 10 provided on the measuring apparatus main body 1. Is connected to a contact probe unit 7 including three contact probes 41 to 43 provided to correspond to the above. And
The control box 6 includes a potentiostat 44 for applying an appropriate bias voltage to the semiconductor substrate 25, and a current for converting a current signal extracted from a terminal 30a connected to the ohmic contact 8 formed on the semiconductor substrate 25 into a voltage signal. The voltage converter 45, the current-voltage converter 4
And an interface board 47 for transmitting and receiving signals to and from the operational amplifier circuit 46 and outputting control signals to the scanning control device 39 and the light source control device 40. 47 is connected to the computer 16.

The opening 3 of the cartridge cover 35
6, the configuration of the counter electrode 9 and the comparative electrode 10 provided so as to contact the upper surface of the polyacrylamide gel 33 will be described with reference to FIGS. 4 (A) and 4 (B). First, as shown in FIG. 3A, platinum is formed on the lower surface of one of the members 49 of the main body 48 formed in an L-shape in plan view, which is the contact surface with the polyacrylamide gel 33, as shown in FIG. A band is provided to form a conductive portion 50, and a terminal 5 made of gold is connected to an end of this member 49 so as to be connected to the conductive portion 50.
1 are formed.

As shown in FIG. 2B, the comparative electrode 10 is provided with an internal liquid (for example, a 1.5 M KCl solution) and a liquid in a rectangular parallelepiped container 52 made of an insulating material such as resin.
g / AgCl is accommodated therein, and one outer wall of the container 52 is plated with gold to form a connection terminal 54.
The terminal 54 and the inner electrode 53 are electrically connected by a silver wire 55, and a liquid junction 56 for making contact with the polyacrylamide gel 33 is formed below the container 52. Incidentally, reference numeral 57 denotes an internal liquid inlet.

Next, the structure of the electrophoretic anode tank 11 and the cathode tank 12 set above the gel cassette 2 will be described with reference to FIGS. 5 (A) and 5 (B). First, the anode tank 11 is formed in a rectangular parallelepiped shape as shown in FIG. 1A, and an injection port 58 for an anode buffer solution is opened in a rectangular shape on the upper surface thereof.
On the lower surface, a rectangular opening 59 is formed in the same direction as the injection port 58. The opening 59 has the same shape and the same size as the rectangular opening 37 in the cartridge cover 35, and is for leading out the anode buffer solution. A rod-shaped anode 60 is provided inside the anode tank 11.
An anode terminal 61 is provided laterally in the same direction as the above and is electrically connected to the anode 60.
62a and 62b are engagement legs inserted into the holes 23a and 23b formed in the cartridge cover 35.

The cathode tank 12 has the same shape and the same size as the anode tank 11, and has a rectangular inlet 64 for a cathode buffer solution on the upper surface and a rectangular opening 64 on the lower surface. 63 are formed in the same direction. In this embodiment, the injection port 63 is formed much larger than the injection port 58. The opening 64 has the same shape and the same size as the rectangular opening 38 in the cartridge cover 35, and is for taking out the cathode buffer solution. Further, a rod-shaped cathode 65 is provided inside the cathode tank 12 in the same direction as the injection port 63,
A cathode terminal 66 electrically connected to the cathode 65 is led out from the inlet 63. Further, 67a, 67
b is a hole 23c, 2 formed in the cartridge cover 35.
It is an engagement leg inserted into 3d. Although not shown, the inlets 58 and 63 are provided with detachable lids, respectively.

In the anode tank 11 and the cathode tank 12 having the above-described structure, the inlet 63 is set on the cartridge cover 35 via a sealing packing 68 as shown in FIG. This packing 68 is made of silicon rubber or the like.
The anode 60 and the cathode 65 are connected to the positive and negative electrodes of the power supply 13 for electrophoresis, respectively, as shown in FIG. The electrophoresis power supply 13 is configured to be controlled by a computer 16.

The cover 14 which covers the upper surface of the gel cassette 2 is made of, for example, a resin and is made of a transparent material.
And a suitable concave portion is formed so that the counter electrode 9 and the comparative electrode 10 arranged so as to be in contact with the polyacrylamide gel 33 can be led out.

Next, the electrophoresis method of the present invention will be described.

(1) The packing 31, the ohmic electrode 8, and the pH sensor 24 are placed on the spot facing surface 21 of the cartridge base 20 in this order. At this time, the sensor surface 27 of the pH sensor 24 is made flush with the upper surface of the cartridge base 20.

(2) The polyacrylamide gel 33 having a predetermined size is placed so as to be in contact with the pH sensor surface 27, and the cartridge cover 35 is set on the polyacrylamide gel 33 to constitute the gel cassette 2. .

(3) The gel cassette 2 set up is set in the two-dimensional scanning device 3.

(4) The anode tank 11 and the cathode tank 12 are set on the cartridge cover 35 via the packing 68.

(5) Phosphoric acid, for example, 0.01 M as an anode buffer solution in the anode tank 11, and 0.05 M, for example, as a cathode buffer solution in the cathode tank 12.
Of sodium hydroxide are injected in each case.

(6) After supplying the sample from the cathode tank 12 to the sample injection recess 34 of the polyacrylamide gel 33 using a syringe, the anode tank 11 and the injection ports 58 and 63 of the cathode tank 12 are covered.

(7) The counter electrode 9 and the reference electrode 10 are set on the polyacrylamide gel 33 through the opening 36 of the cartridge cover 35 in a predetermined state.

(8) The transparent cover 14 is placed on the polyacrylamide gel 33. Thereby, all of the polyacrylamide gel 33, the counter electrode 9, and most of the reference electrode 10 are covered. Then, the ohmic electrode 8, the counter electrode 9, and the comparative electrode 10 are connected to the control box 6 via the contact probe unit 7.

(9) In the state of (8), the electrophoresis DC power supply 13 is operated to perform electrophoresis. The electrophoresis conditions are, for example, 100 V for 1 hour, 200 V for 1 hour, 50 hours.
30 minutes at 0V.

(10) After performing the electrophoresis, the laser beam 5 is irradiated while the bias voltage is applied by the potentiostat 44 and the two-dimensional scanning device 3 is used.
Is operated to scan the gel cassette 2 in the two-dimensional direction, the semiconductor substrate 2 of the sensor 24 in the gel cassette 2 is scanned.
5 is sequentially and two-dimensionally irradiated by the laser beam 5. By the two-dimensional irradiation of the laser light 5, a current signal corresponding to the potential at each position can be extracted, and the position signal (X, Y) and the current amount are processed by the computer 16, so that the sensor surface 27 is obtained. The pH value of the polyacrylamide gel 33 in contact with the polyacrylamide gel 33 can be obtained with a positional resolution of 100 μm.

(11) The pH value obtained by the above measurement is displayed in correspondence with the position of the measurement point, and the pH value is determined with respect to the distance from the reference end (for example, the left end) of the polyacrylamide gel 33. Can be grasped how is fluctuating.

(12) Counter electrode 9, reference electrode 10, anode cell 11, cathode cell 12, and cartridge cover 35
Is removed to expose the polyacrylamide gel 33 entirely. At this time, the buffer solution on the polyacrylamide gel 33 is also removed.

(13) The polyacrylamide gel 33
Is stained. This staining is performed, for example, as follows. The polyacrylamide gel 33 is treated with sulfosalicylic acid for 3 hours.
Soak for 0 minutes.・ Immerse in Coomassible + ethanol + acetic acid for 5 minutes.・ Immerse in ethanol + acetic acid for 5 minutes.

As a result of the above staining, the protein to be measured is stained red, and a red band is formed in the polyacrylamide gel 33. Then, it is confirmed using the CCD camera 15 how many positions (places) this band forms from the reference end of the polyacrylamide gel 33. Observation data is input to the computer 16 by the CCD camera 15.

(14) Based on the distribution of the pH values in the polyacrylamide gel 33 obtained by the measurement in the above (11), the pH values at the positions of the bands obtained by the staining in the above (13) are collated. Pi of the protein can be obtained.

In the first embodiment, the electrophoresis and the pH distribution measurement can be performed in one apparatus 1, and the electrophoresis can be performed accurately and easily.

In the first embodiment, the electrophoresis and the pH distribution measurement are performed by one measuring device main body 1.
After the pH measurement, the polyacrylamide gel 33 after the pH measurement was removed from the main body 1 of the measuring apparatus, and the polyacrylamide gel 33 was taken out from the gel cassette 2 and then subjected to the method shown in the above (13). The pH value at the position of the band obtained by the staining is compared based on the distribution of the pH value in the polyacrylamide gel 33 obtained by the measurement in the above (11), thereby obtaining the pI of the protein. May be obtained.

Next, FIG. 6 shows a second embodiment of the present invention. In this embodiment, instead of performing electrophoresis in the measurement device main body 1, after performing electrophoresis using another electrophoresis device, the pH is measured, and then the gel is colored. ing.

That is, as shown in FIG. 6, (21) a polyacrylamide gel 33A is used for electrophoresis by using an electrophoresis apparatus generally used conventionally, for example, a slab type polyacrylamide gel electrophoresis apparatus 70.
Is performed.

(22) After performing the electrophoresis, the polyacrylamide gel 33A is taken out of the electrophoresis apparatus 70, and a part thereof is cut out. The cut gel 33a is made into a gel cassette 2 using the cartridge base 20 and the cartridge cover 35 in the same manner as the above gel cassette, and the gel cassette 2 is set in the two-dimensional scanning device 3 of the measuring device main body 1, and the above (10) Gel 33 in the same manner as described in
Measure the pH value distribution of a.

(23) The pH value obtained by the above measurement is displayed in correspondence with the position of the measurement point, and the gel 33
For the distance from the reference end of a (for example, the left end),
It is possible to grasp how the pH value fluctuates.

(24) The gel not used in the above measurement was
Using a suitable container such as a vat, stain by the method shown in (13) above, and visually determine how far (position) the protein to be measured forms a band from the reference end. Confirm.

(25) Based on the distribution of the pH value in the gel 33a obtained by the measurement in the above (22), the pH value of the position of the band obtained by the staining in the above (24) is compared to obtain the protein. Can be obtained.

In the second embodiment, the gel 3
The pH measurement of 3a is performed using the measuring device main body 1 shown in the first embodiment.
The measurement may be performed using an optical scanning type two-dimensional density distribution measuring device as disclosed in JP-A-13580 or JP-A-9-274007.

In each of the above embodiments, the light source 4 is fixed, and the gel cassette 2 is scanned using the two-dimensional scanning device 3 so that the semiconductor substrate 25 of the sensor 24 in the gel cassette 2 is separated from the light source 4. The laser light 5 is used to sequentially irradiate two-dimensionally. Alternatively, the gel cassette 2 may be fixed and the light source 4 may be two-dimensionally scanned.

Next, as a third embodiment of the present invention, an electrophoresis apparatus having a more compact overall structure, easy handling, and easier portability will be described with reference to FIGS. I do.

That is, in FIG. 7 and FIG.
Is a case made of, for example, resin or an appropriate metal, and is open at the top and the front. At the center of the bottom of the case 81, a light irradiating section 82 composed of a plurality of LED arrays is formed. The light irradiating section 82 is configured such that LEDs are sequentially turned on by a control signal from a control / power supply section 83 described later, and the semiconductor substrate 25 of the sensor 24 of the electrophoretic section 91 described below is sequentially irradiated with laser light. It is configured. Reference numeral 83 denotes a control / power supply unit having a function of supplying power while controlling control and signal processing, and also has a function of the control box 6 and the power supply 13 for electrophoresis in the first embodiment.

In the case 81, connection portions 8A, 9A, and 10 of an ohmic electrode counter electrode and a reference electrode to be described later are provided.
A signal connection portions 84, 85, 86 corresponding to A and power supply connection portions 87, 88 for anode and cathode connection terminals 61, 66 housed in the anode tank 11 and the cathode tank 12, respectively. These connecting portions 84 to 88
Is connected to the control / power supply unit 83. Reference numeral 89 denotes an external connection unit, which is configured to connect a computer and a power cable similar to the computer 16 of the first embodiment. Guide grooves 90 for guiding and holding an electrophoresis unit 91 described later are formed on both sides inside the case 81.

Reference numeral 91 denotes an electrophoresis unit which is set in the case 81 so as to be freely inserted into and removed from the case 81. The gel cassette 2, the anode tank 11, and the cathode tank 1 in the first embodiment are provided.
2 is set via a packing (not shown). 8A is the semiconductor substrate 25 of the sensor 24.
Is a connection part of the ohmic electrode provided in the first embodiment.

The electrophoresis section 91 connects the left and right ends 2 a and 2 b of the gel cassette 2 with the guide grooves 9 in the case 81.
When the electrophoresis section 91 is completely inserted into the case 1, the signal connection section 8A of the ohmic electrode and the connection terminals 61 and 66 of the anode and the cathode are connected to the signal connection section. The unit 84 is configured to be connected to the power connection units 87 and 88, respectively.

Reference numeral 92 denotes a cover body for detachably covering the upper part of the gel cassette 2. Although not shown in detail, the cover body 92 has the same configuration as the cover 14 shown in the first embodiment. The counter electrode and the comparative electrode having the same configuration as the counter electrode 9 and the comparative electrode 10 shown in the first embodiment are integrally incorporated into the cover 14A. Reference numerals 9A and 10A are connection portions of the counter electrode and the comparison electrode.

When the cover 92 is set so as to cover the polyacrylamide gel 33 of the gel cassette 2, the connection portion 9 of the counter electrode and the reference electrode is set.
A and 10A are connected to the signal connection units 85 and 86, respectively.

Reference numeral 93 denotes a cover for closing the opening of the case 1. An optical image observation device 94 such as a CCD camera is provided on the top of the cover 93. In this case, the entirety of the polyacrylamide gel 33 is observed. Reference numeral 95 denotes a signal extraction unit of the optical image observation device 94. By connecting a signal cable (not shown) to a computer to the signal extraction unit 95, an optical image observation device 94 is provided.
Can be imported into a computer.

In the electrophoresis apparatus configured as described above, a computer similar to the computer 16 in the first embodiment is connected to the external connection portion 89 of the case 81, and the main body 91 of the measurement apparatus is inserted into the case 81. By setting the cover 92 and the cover 93 in a predetermined state, the configuration is the same as that of the electrophoresis apparatus of the first embodiment.

In the apparatus configured as described above, the pH of the polyacrylamide gel 33 can be measured and the electrophoresis can be performed as in the first embodiment.

After the electrophoresis, for example, the polyacrylamide gel 33 is colored in the same manner as in the above embodiment, and the position of the band can be confirmed by the optical image observation device 94. Therefore, the pI of the protein can be obtained by checking the pH value at the position of the band obtained by staining based on the previously obtained distribution of the pH value.

In this embodiment, the polyacrylamide gel 33 is once removed from the gel cassette 2 and
After staining outside the device, the position of the band may be confirmed by the optical image observation device 94.

According to the third embodiment, since there are no mechanically movable parts, the number of failures is small, and the whole apparatus can be made smaller and more compact.

In the apparatus according to the third embodiment,
The case 81 may include a microcomputer that controls the entire system and performs signal processing.

[0074]

According to the present invention, isoelectric focusing can be performed easily, accurately and in a short time.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing an overall configuration of an electrophoresis apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view schematically showing a main part of the electrophoresis apparatus.

FIG. 3 is an exploded perspective view showing a configuration of a main part of the electrophoresis apparatus.

FIG. 4A is an enlarged perspective view showing an example of a counter electrode incorporated in the electrophoresis apparatus, and FIG. 4B is an enlarged perspective view showing an example of a comparative electrode incorporated in the electrophoresis apparatus.

FIG. 5A is an enlarged perspective view showing an example of an anode cell incorporated in the electrophoresis apparatus, and FIG. 5B is an enlarged perspective view showing an example of a cathode cell incorporated in the electrophoresis apparatus.

FIG. 6 is a diagram for explaining a second embodiment of the present invention.

FIG. 7 is a perspective view schematically showing a configuration of an electrophoresis apparatus according to a third embodiment of the present invention.

FIG. 8 is a longitudinal sectional view of the electrophoresis apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical scanning type two-dimensional pH distribution measuring device, 11 ... Anode tank, 12 ... Cathode tank, 13 Power supply for electrophoresis, 24 ... p
H sensor, 33: gel, 60: anode for electrophoresis, 6
5. Cathode for electrophoresis.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Shuji Takamatsu 2 Higashi-cho, Kichijoin-miya, Minami-ku, Kyoto, Kyoto Prefecture Inside of Horiba Seisakusho Co., Ltd. Inside HORIBA, Ltd. (72) Inventor Tsuyoshi Nakanishi 2 Higashi-cho, Kichijoin-gu, Minami-ku, Kyoto, Kyoto Prefecture Inside HORIBA, Ltd. (72) Inventor Yoshio Tsujino 1-20-6 Mukonoso, Amagasaki City, Hyogo Prefecture

Claims (2)

[Claims] 1. A gel after electrophoresis is brought into contact with a pH sensor of an optical scanning type two-dimensional pH distribution measuring device, a pH value at each point of the gel is directly measured, and the measurement result is recorded. Next, the measurement object contained in the gel is stained by an appropriate method, the position of the band obtained by this staining is confirmed by visual or optical means, and the position of the band is obtained by the pH measurement. An electrophoresis method, wherein the pI of the object to be measured is determined by comparing the pH value with the pH value. 2. An optical scanning type two-dimensional pH distribution measuring device having a planar pH sensor on which a gel is placed, a power supply for electrophoresing the gel, an anode and a cathode for electrophoresis, and An electrophoresis apparatus comprising: a solution tank containing a solution for immersing an electrode.