JP2006119158A - Electrophoresis device and electrophoresis method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid or reduce adverse effects due to abnormality of a current-carrying passage, in an electrophoresis device. <P>SOLUTION: In this electrophoresis device, current flowing through the current-carrying passage at electrophoresis is measured, the state of a separation medium is detected, and voltage application to the current carrying passage is suspended. Preferably, the presence/absence of a bubble inside the separation medium is detected by the time rate of change of the current value, and voltage application to the current carrying passage is suspended in time of generation. When bubbles, dust or the like are present inside the separation medium in the electrophoresis device that applies high voltage, the adverse effects, such as electric discharges or electroconductivity failures are generated. However, if suspending the electrophoresis is suspended immediately after the bubble generation, for example, the adverse effects, such as the electric discharge or short circuiting, can be avoided or reduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a capillary electrophoresis apparatus for separating and analyzing samples such as nucleic acids and proteins.

As an example of a capillary electrophoresis device, Applied Biosystems (Applied
Biosystems) model 3100 is known. This apparatus can detect the current flowing between the electrode in the cathode side buffer solution and the high voltage power supply and the current flowing between the electrode in the anode side buffer solution and the ground.

Japanese Patent Laid-Open No. 10-253587

  An object of the present invention is to avoid or reduce the adverse effects caused by abnormalities in the current path.

  The present invention relates to an electrophoresis apparatus and method for measuring a current flowing in an energization path during electrophoresis and detecting a state of the energization path. Preferably, the present invention relates to an apparatus and a method for detecting an abnormal situation such as bubble generation from a change in the current value of a current path and taking countermeasures such as stopping electrophoresis. As a result, it is possible to avoid adverse effects such as discharge caused by continuing electrophoresis after occurrence of an abnormal situation.

  The present invention also relates to an electrophoresis apparatus and method for measuring a current in an energization path when a predetermined voltage is applied and detecting a state of the energization path. Preferably, the present invention relates to an electrophoresis apparatus and method for discriminating whether a current path is suitable for electrophoresis from a current value when a voltage that does not induce adverse effects such as discharge is applied. Thereby, the state of the separation medium can be easily determined. Even in an abnormal state where the separation medium is not filled in the capillary, no adverse effect such as discharge is induced.

  According to the present invention, it is possible to avoid and reduce the adverse effects caused by the abnormality of the current path.

  The above and other novel features and benefits of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic diagram of an electrophoresis apparatus according to the present embodiment. Hereinafter, the configuration of the present apparatus will be described with reference to FIG.

  This apparatus includes a detection unit 116 for optically detecting a sample, a thermostatic chamber 118 for maintaining the capillary at a constant temperature, a transporter 125 for transporting various containers to the capillary cathode end, and applying a high voltage to the capillary. A high-voltage power source 119 for detecting the current generated from the high-voltage power source, a second ammeter 112 for detecting the current flowing through the anode electrode, and one or a plurality of capillaries. A capillary array 117 and a pump mechanism 102 for injecting a polymer into the capillaries are configured.

  The capillary array 117 is an exchange member including 96 capillaries, and includes a load header 129, a detection unit 116, and a capillary head. When changing the measurement method, the capillary array is replaced and the length of the capillary is adjusted. When the capillary is damaged or quality is deteriorated, it is replaced with a new capillary array.

  The capillary is composed of a glass tube having an inner diameter of several tens to several hundreds of microns and an outer diameter of several hundreds of microns, and the surface is coated with polyimide in order to improve the strength. However, the light irradiation portion irradiated with the laser light has a structure in which the polyimide coating is removed so that the internal light emission easily leaks to the outside. The inside of the capillary 101 is filled with a separation medium for giving a migration speed difference during electrophoresis. Although the separation medium has both fluidity and non-fluidity, a fluid polymer is used in this embodiment.

  The detection unit 116 is a member that acquires information depending on the sample, and is irradiated with excitation light and emits light having a wavelength depending on the sample. The vicinity of the light irradiation part of 96 capillaries is arrayed and fixed on the optical flat plane with an accuracy of several microns in height. At the time of electrophoresis, two substantially coaxial laser beams are irradiated from both sides and are continuously transmitted through all the light irradiation units. By this laser light, information light (fluorescence having a wavelength depending on the sample) is generated from the sample and emitted from the light irradiation unit to the outside. This information light is detected by the optical detector 115 to analyze the sample.

  Each of the capillary cathode side ends 127 is fixed through a metal hollow electrode 126, and the capillary tip protrudes from the hollow electrode 126 by about 0.5 mm. Further, all the hollow electrodes provided for each capillary are integrally attached to the load header 129. Further, all the hollow electrodes 126 are electrically connected to a high-voltage power source 119 mounted on the apparatus main body, and operate as cathode electrodes when a voltage needs to be applied such as electrophoresis or sample introduction.

  The capillary end (other end) opposite to the capillary cathode end 127 is bundled together by a capillary head. It is a member that can be attached and detached in a bunch of pressure and pressure. The capillary head can be connected to the block 107 in a pressure resistant manner. Then, the syringe 106 fills the capillary with the new polymer from the other end. Refilling the polymer in the capillary is performed for each measurement in order to improve the measurement performance.

The pump mechanism 102 includes a syringe and a mechanism system for pressurizing the syringe. A block 107 is a connection part for communicating the syringe 106, the capillary array 117, the anode buffer container, and the polymer container. The pump mechanism system includes an electric motor 103, a linear actuator 132, and a moving body 104 that contacts the plunger of the syringe and transmits force. The electric motor 103 is rotated forward, the moving body 104 is pressed against the plunger of the syringe 106, the polymer in the syringe is discharged, and the polymer is injected into the capillary via the block 107. In addition, the moving body 104 is provided with a hook 105 that is electrically pulled in and out, and the polymer in the polymer container 109 is sucked into the syringe 106 by reversing the motor while the hook 105 is hooked on the plunger. be able to. In addition, here, forward rotation and reverse rotation of the motor are forward rotation of the motor when the moving body moves in the direction of pushing the syringe, and reverse rotation is reverse rotation. The check valve 108 is located between the polymer container 109 and the block 107, and has a function of allowing the polymer to flow in the direction from the polymer container 109 to the block 107, and conversely blocking the outflow of the polymer from the block 107 to the polymer container 109. is doing. Therefore, the polymer is prevented from flowing back into the polymer container 109 when the polymer is injected into the capillary array 117. The electric valve 113 opens and closes the flow path between the block 107 and the anode buffer container 110, and closes the flow path at least when the polymer is injected into the capillary to prevent the polymer from flowing out into the anode buffer container 110. It is out. Further, when it is necessary to pass a current between the cathode and the anode such as electrophoresis, the flow path is opened.

  The optical detection unit includes a light source 114 for irradiating the detection unit 116 and an optical detector 115 for detecting light emission in the detection unit 116. When the sample in the capillary separated by electrophoresis is detected, the light source 114 irradiates the light irradiation part of the capillary, and the optical detector 115 detects light emission from the light irradiation part.

  The conveyor 125 includes three electric motors and a linear actuator, and is movable in three axes in the vertical direction, the horizontal direction, and the depth direction. Further, at least one or more containers can be placed on the moving stage 130 of the transporter 125. Further, the moving stage 130 is provided with an electric grip 131, and each container can be grasped and released. Therefore, the buffer container 121, the cleaning container 122, the waste liquid container 123, and the sample container 124 can be conveyed to the cathode end as necessary. Note that unnecessary containers are stored in a predetermined container in the apparatus.

  The apparatus main body 101 is used in a state of being connected to the control computer 128 with a communication cable. The operator can control the functions of the apparatus by the control computer 128 and exchange data detected by the detector in the apparatus.

  FIG. 2 is a high-voltage power supply circuit diagram showing the voltage control mechanism of the present apparatus. Hereinafter, the voltage control mechanism will be described with reference to FIG.

  The voltage control mechanism includes a microcomputer 201, a controller 202, a high voltage power supply 203, a first ammeter 204, and a second ammeter 207. The high voltage power supply 203 applies a voltage to the energization path based on the control of the controller. The energization path is a hollow electrode 205, a buffer solution 121 filled in the buffer container 121, an electrophoresis path, a buffer solution 110 filled in the cathode buffer container 110, and an electrode (GND) 206. The electrophoresis path is a polymer filled in a capillary, a block 107, and a connecting pipe (a flow pipe connecting the block 107 and the anode buffer container 110).

  The high-voltage power supply 203 is electrically connected to the hollow electrode 205 via the first ammeter 204 and the electrode (GND) 206 via the second ammeter 207. When a voltage of several tens of kilovolts is applied to both ends, an electric field is generated in the direction from the hollow electrode to the electrode (GND). Due to this electric field, a negatively charged sample such as a nucleic acid moves from the capillary cathode side end 127 to the detection unit 116.

The first ammeter 204 detects the current flowing from the high-voltage power supply 203 to the hollow electrode 205 and transmits the current value to the microcomputer 201. The second ammeter 207 detects a current flowing from the electrode (GND) 206 to the GND, and transmits the current value to the microcomputer 201. Usually, a second ammeter is used for checking a current value and its fluctuation described later. This is because the current value flowing through the electrophoresis path is more directly reflected. When there is a leakage between the first ammeter and the second ammeter, the value indicated by the first ammeter includes the current value of the leakage, whereas the numerical value indicated by the second ammeter is the leakage current. Is not included. That is, the amount of current that flows through the electrophoresis path is detected. Between the first ammeter and the second ammeter is a portion where a medium having a relatively higher resistance than metals such as buffers and polymers is interposed, and there are many connection portions such as blocks and capillaries. Therefore, it can be said that this is a portion in which leakage is likely to occur in the circuit of FIG.

  The microcomputer 201 reads current values from the first ammeter 204 and the second ammeter 207 and performs calculation. Then, the controller 202 is commanded to control the high-voltage power supply 203 to various states such as high voltage application, low voltage application, and voltage forced cutoff. Further, it can communicate with a computer 128 arranged outside the apparatus main body 101.

Next, preparation before starting electrophoresis will be described. The operator sets the following in the device before starting the measurement. An anode buffer container 121 containing a buffer solution, a washing container 122 containing pure water for capillary washing, a waste container 123 for discharging the polymer in the capillary, a polymer container 109 containing a polymer as a separation medium, and A sample container 124 containing a sample to be measured. The anode buffer container 110 is filled with a buffer enough to immerse both the electrode (GND) 111 and the communication pipe. Further, the cathode buffer container 121 fills the buffer so that the hollow electrode 126 and the capillary cathode end 127 are sufficiently immersed. This is because if the buffer solution is insufficient or the measurement is started with the buffer container being empty, there is a risk that a discharge will occur between the negative electrode having a high potential and another having a low potential when a high voltage is applied. Furthermore, it is desirable that both buffer levels are equal. This is to prevent the polymer in the capillary from moving due to the pressure due to the height difference. In addition, all of the flow paths used for electrophoresis or the flow paths used to transport the polymer to the flow paths need to be filled with the polymer before starting the measurement. Usually, when the apparatus is used continuously, the flow path is filled with a polymer. Also, when replacing the flow path with polymer after replacement of the capillary array, cleaning of the flow path, etc., the operator operates the pump mechanism of the device or manually operates the syringe, etc. Is replaced with a polymer. Thereafter, the operator visually confirms that there are no remaining bubbles or foreign matter in the flow path. However, there is a possibility that bubbles or foreign matters remain in the flow path due to an operation error or oversight. In particular, very small bubbles are difficult to catch visually. Such bubbles and foreign matters in the flow path may act as a large resistance when the electrophoretic path is energized, and there is a risk that the analysis accuracy may be lowered due to poor conduction, or the components may be damaged due to discharge. In addition, even a very small bubble may expand due to Joule heat during electrophoresis and eventually block the flow path to cause the discharge as described above. Therefore, the operator needs to pay sufficient attention to the state of the flow path before starting the analysis. Then, the operator starts the measurement after inputting the setting according to the analysis to be started from the control computer. Here, the analysis is an analysis in which a high voltage is applied to the electrophoresis path.

  FIG. 3 is a flowchart showing a flow from the start of analysis to the end of analysis. Hereinafter, the flow of analysis will be described with reference to FIG. The apparatus starts the analysis in response to a command from the computer 128 (301). In preparation for injecting the polymer into the capillary, the apparatus first carries the waste container to the capillary cathode end by means of a carrier mounted on the apparatus (302). Thereafter, the polymer is injected into the capillary by a pump mechanism provided in the apparatus (303). After the injection of a predetermined amount is completed, the transporter transports the cleaning container to the capillary cathode portion, and performs cleaning by immersing the capillary cathode end in pure water in the cleaning container (304). Next, the transporter transports the buffer container to the capillary cathode part (305). And the current path state confirmation (current value confirmation at the time of low voltage application) is performed.

  The energization path state confirmation is a procedure including weak voltage application (306), current value check (307), error display (316), and operator response (317). As a result, for example, an abnormal situation such as a shortage of the amount of liquid in the buffer, remaining bubbles in the electrophoresis path, and contamination of dust can be confirmed. For this reason, it is possible to avoid the risk of applying a high voltage in the presence of these preparatory steps and causing a discharge in the electrophoresis path.

  In the weak voltage application (306), a voltage lower than that of the pre-electrophoresis (308), sample introduction (311), and electrophoresis (313) is applied. The magnitude of the voltage is such that the discharge does not occur even when an abnormal situation such as a shortage of the amount of liquid in the buffer, residual bubbles in the electrophoresis path, or contamination of dust occurs. In this embodiment, a voltage of 1 kilovolt is applied, and the current value is confirmed after another 3 seconds. This is because an accurate current value corresponding to the voltage is grasped in consideration of the rise time of the current. A waiting time of several seconds is sufficient. The numerical value detected at this time is a value read from the second ammeter 207 on the anode side.

  In the current check (307), the current value detected by the weak voltage application (306) is compared with a threshold value. The threshold value is determined in consideration of parameters affecting the current value such as the type of application, specifically the length, number of capillaries, and type of polymer used. In practice, the current value obtained under each use condition can be experimentally investigated in advance, and a value about half to one third can be used as the threshold value. If the current value is lower than the threshold value, factors that inhibit the current, such as a state different from normal, for example, insufficient buffer liquid amount as described above, and residual bubbles in the electrophoresis path are estimated. It is determined that there is an abnormality (error) in the migration path. If an abnormality is confirmed, the voltage is shut off immediately to prevent damage to the parts due to electric discharge. Further, an error message is displayed on the display of the control computer (316), and an operator response is requested (317). The operator who has recognized the error visually checks whether there are bubbles or foreign matters in the electrophoresis path. If an abnormality is confirmed, take countermeasures against the abnormality and start the analysis again or ask a serviceman for maintenance. For example, when the cause of the abnormality is mixing of bubbles or foreign matter, the pump mechanism 102 or the syringe 106 is manually operated to refresh the inside of the flow path. Note that the comparison of current values as described above and the determination of abnormality or normality are executed on software. Further, a threshold value used for determining whether or not it is normal is also stored in the software.

  Also, this current path state confirmation can be performed before sample introduction (311) and electrophoresis (314), respectively. In this way, mainly at the initial preparation stage, the buffer capacity is insufficient and the buffer solution is not in contact with the electrode, and relatively large bubbles are mixed in the electrophoresis path and conduction is not achieved. You can avoid mistakes.

  If there is no abnormality in the energization path, a predetermined voltage is applied and preliminary electrophoresis is started (308). Preliminary electrophoresis is intended to bring the state of the polymer in the capillary into a state suitable for analysis prior to the original analysis step of performing electrophoresis from sample introduction. In preliminary electrophoresis, a voltage of about several to several tens of kilovolts is usually applied for several to several tens of minutes. When the pre-electrophoresis is completed, the tip of the capillary cathode is again washed with the washing container (309), and then the sample container 124 is transported to the capillary cathode end. When a voltage of about several kilovolts is applied to the capillary cathode electrode in the sample liquid stored in the sample container 124, an electric field is generated between the sample liquid and the anode side electrode. This electric field introduces the sample in the sample liquid into the capillary (311).

  After the introduction of the sample is completed, the capillary cathode end is washed with a washing container (312), and then the buffer container is conveyed again to the capillary cathode end (313). Then, electrophoresis is started by applying a predetermined voltage (314).

  Electrophoresis (314) is to impart mobility to the sample in the capillary by the action of the electric field generated between the cathode and anode buffer, and to separate the sample by the difference in mobility depending on the nature of the sample. The separated samples are optically detected in order from the one that reaches the detection unit. For example, when the sample is DNA, a difference in mobility occurs depending on the base length, and consequently, the DNA passes through the detection unit in order from a DNA having a short base length with a fast moving speed. Since a fluorescent substance is attached to DNA in advance, it can be optically detected by the detection unit. Usually, the measurement time and voltage application time are set according to the sample having the longest migration time.

  When a predetermined time elapses from the start of voltage application and the planned data is obtained, the voltage application is stopped and the electrophoresis is terminated (315).

  The above is a series of measurement sequences.

  In the above-described preliminary electrophoresis (308), sample introduction (311), and electrophoresis (314), the occurrence of abnormality in the electrophoresis path is detected by monitoring the current value fluctuation. In the above three procedures, a high voltage of several to several tens of kilovolts is applied to the electrophoresis path. At this time, for example, if the application of a high voltage is continued in a state where minute bubbles that cannot be detected by the previous confirmation of the state of current application by a weak voltage remain in the electrophoresis path, Will grow. If the energization path is blocked by the volume-expanded bubbles, it can cause discharge. For this reason, the apparatus of this embodiment has a function of detecting an abnormality that occurs in the electrophoresis path during voltage application.

  FIG. 4 is a diagram illustrating an abnormality detection flow in the electrophoresis path. Hereinafter, a method for detecting occurrence of abnormality in the electrophoresis path by monitoring current value fluctuation will be described with reference to FIG.

  First, voltage application is started, and preliminary electrophoresis, sample introduction, or electrophoresis is started (401). Subsequently, abnormal current measurement is started, and this function for interrupting measurement when an abnormality in the electrophoresis path is detected is enabled (402). Then, the current value is acquired from the second ammeter 207 (403). If there is a current value acquired in the past, the current value is compared with the past value to determine the state of the energization path (404). When the current value is normal, the current value is stable, and even if it varies with time, its degree is gentle. On the other hand, when the electrophoresis path is blocked by bubbles or the like, the current value changes rapidly. Therefore, it is possible to instantaneously detect an abnormality in the electrophoretic path that occurs during voltage application by monitoring the degree of fluctuation of the current value, specifically, the gradient of the current value. Here, when the amount of decrease in the current value per unit time exceeds the threshold, it is determined that an abnormality has occurred in the energization path. This determination method will be described in detail below. If an abnormality is found in the current path, turn off the voltage and stop the measurement to prevent discharge. Thereafter, an error is displayed (407), and an operator response is requested (408). The operator who has recognized the error visually checks whether there are bubbles or foreign matters in the electrophoresis path. If an abnormality is confirmed, take countermeasures against the abnormality and start the analysis again or ask a serviceman for maintenance. For example, when the cause of the abnormality is mixing of bubbles or foreign matter, the pump mechanism 102 or the syringe 106 is manually operated to refresh the inside of the flow path. If no abnormality is found in the above determination (404), it is confirmed whether or not the voltage is continuously applied (405). When turning off the voltage, the current value monitoring is stopped and the voltage is turned off. When the voltage is continuously applied, the current value is again called and the processing from (403) to (405) is repeated. FIG. 5 is a schematic explanatory diagram of the current fluctuation detection and comparison method, and relates to “comparison with previous numerical value” in FIG. Hereinafter, a method for determining the state of the migration path from the average value of the current values will be described with reference to FIG. In the process of (404), there is a method of comparing the obtained current values as they are, but in this embodiment, an average value for a certain period of time is taken for comparison. This operation has the effect of smoothing the current value for a certain period, and can reduce the influence of the minute fluctuation of the current value caused by the detection accuracy, suddenly generated electrostatic noise, and the like.

While the voltage is applied, the microcomputer 201 reads and checks the fluctuation of the current value at a cycle of 100 msec. The read current value is sequentially recorded as I ₁₀ for the last read value and I ₉ , I ₈ ,. When the current value is read, the last five values read, that is, the average value from I ₆ to I ₁₀ is calculated. Further, five values obtained before that, that is, an average value from I ₁ to I ₅ are calculated. That is, their average value is 100
The average value for 500 msec when the current value is read in the msec cycle is shown. Here, the difference between the latest average value (I _ave. (N)) for 500 msec and the average value (I _ave. (N−1)) for the previous 500 msec is calculated as the fluctuation (ΔI) of the current value (I). ). In a normal state, the current value (I) takes a stable value, and ΔI indicating the fluctuation is almost zero. However, as described above, when a situation occurs in which bubbles in the channel grow due to heat generated by the current and the channel is blocked, the current value (I) decreases rapidly, and ΔI indicating the fluctuation is To rise. Therefore, a certain threshold value is set, and when the fluctuation of the current value exceeds this threshold value, the voltage is instantaneously removed from the electrophoresis path. Further, it is desirable that this threshold is a level that cannot be observed in a normal state and that it easily exceeds when an abnormality occurs in the electrophoresis path such as blockage of the flow path by bubbles. Actually, since the fluctuation (ΔI) in the current value caused by the detection accuracy at the normal time is smaller than the fluctuation at the time of occurrence of the abnormality, it is possible to set a suitable threshold as described above. Also, here, the difference between I (n) and I (n-1) is defined as the fluctuation of the current value.
The fluctuation of the current value can also be obtained from the ratio of I (n) and I (n-1).

  It should be noted that abnormality detection in the electrophoresis path can also be performed by changing the current value. For example, the current value when bubbles are generated in the electrophoresis path is predicted and set as a threshold value. This is sequentially compared with the current value, and when the current value falls below the threshold value, the electrophoresis is stopped as a blockage of the flow path due to bubbles.

  FIG. 6 is a schematic explanatory diagram of current change and current fluctuation detection, and shows function change from the start of measurement to detection of an abnormal state. Hereinafter, changes in actual current value (I) and current value fluctuation (ΔI) will be described with reference to FIG. In the upper diagram of FIG. 6, the horizontal axis indicates the elapsed time, and the vertical axis indicates the current value. In addition, this figure shows when the voltage is applied at a certain point and then once becomes stable, and the bubble expands as the temperature in the channel rises, and the bubble closes the channel at a certain point. It shows the current change. In the lower diagram of FIG. 6, the horizontal axis shows the elapsed time, and the vertical axis shows the fluctuation of the current value obtained by the method described in FIG. Moreover, this figure has shown the fluctuation | variation of the electric current value until a bubble obstruct | occludes a flow path after an electric current value becomes a stable state.

  As shown in the upper diagram of FIG. 6, when a voltage is applied, a current corresponding to the voltage is generated. Actually, it takes a little time until the current value (I) rises from the voltage application, but takes a stable value as soon as there is no abnormality in the electrophoresis path. Further, even if minute bubbles that do not reach the flow path are mixed in the electrophoresis path, the current value (I) is constant. When bubbles that grow to the extent that the electrophoretic path is blocked are generated due to heat generation due to current, the bubbles become a large resistance component, and the current value (I) is greatly reduced. In addition, the current value is drastically reduced as a result of accidents such as short-circuiting of the high-voltage power supply and interruption of the electrophoresis path by an insulator.

  The fluctuation (ΔI) of the current value corresponding to this current change is as shown in the figure below. While the current value (I) is constant, the fluctuation (ΔI) of the current value continues to be a value close to zero. However, when bubbles are generated and the current value (I) decreases, the current value fluctuation (ΔI) increases, and when the threshold value is reached, an abnormal current value fluctuation is detected.

  If a threshold value of several microamperes is set in a system in which a normal current flows about several hundred microamperes, an electrophoretic path abnormality such as generation of bubbles can be detected by the method described so far.

  In addition, when the voltage value is changed during voltage application, the current value also changes at the same time, so this function may not work well. That is, there is a possibility of erroneous detection. In order to prevent this, when changing the voltage, there is a method of stopping the abnormal current detection function in advance and restarting it when the current ground enters the stable region again.

  Alternatively, when the voltage is changed only in the increasing direction, the current decreases when bubbles are generated. Therefore, there is a method of ignoring the variation in the direction in which the current increases and focusing only on the decreasing direction. In this case, the timing of voltage application and abnormal fluctuation detection is reversed, that is, no erroneous detection occurs even when a voltage is applied after the start of abnormal fluctuation detection.

  Further, the present invention for detecting an electrophoretic path abnormality from a current value and its variation is a system that uses a non-flowable separation medium, or a system that does not replace the separation medium in the capillary for each analysis. It is clear that the system functions effectively in a system that suffers harmful effects due to abnormalities such as bubble generation in the electrophoresis path.

It is the schematic of the electrophoresis apparatus concerning a present Example. It is a high voltage power supply circuit diagram which shows the voltage control mechanism of this apparatus. It is a flowchart which shows the flow from an analysis start to an analysis end. It is a flowchart which shows the abnormality detection flow in an electrophoresis path. It is a schematic explanatory drawing of a current fluctuation detection comparison method. It is a schematic explanatory drawing of a current change and a current fluctuation detection.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Apparatus main body, 102 ... Pump mechanism, 103 ... Electric motor, 104 ... Moving body, 105 ... Hook, 106 ... Syringe, 107 ... Block, 108 ... Check valve, 109 ... Polymer container, 110 ... Anode buffer container, 111 DESCRIPTION OF SYMBOLS ... Electrode (GND), 112 ... 2nd ammeter, 113 ... Electric valve, 114 ... Light source, 115 ... Optical detector, 116 ... Detection part, 117 ... Capillary array, 118 ... Constant temperature bath, 11 ... 9 High voltage power supply, 120 DESCRIPTION OF SYMBOLS 1st ammeter, 121 ... Buffer container, 122 ... Cleaning container, 123 ... Waste liquid container, 124 ... Sample container, 125 ... Conveyor, 126 ... Hollow electrode, 127 ... Capillary cathode end, 128 ... Control computer, 129 ... Road header, 130 ... moving stage, 131 ... grip, 132 ... linear actuator.

Claims (20)

An electrophoresis apparatus comprising the following configuration;
(1) One or more capillaries that are filled with a separation medium that separates the sample, and that include an introduction end portion into which the sample is introduced and a light irradiation portion that is irradiated with light;
(2) Excitation optical mechanism for irradiating light to the light irradiation unit;
(3) a light receiving optical mechanism for detecting light emitted from the light irradiation unit;
(4) a detection mechanism for acquiring information depending on the current flowing in the current path;
(5) A power supply mechanism that applies a voltage to an energization path including at least the introduction end and the light irradiation unit and cuts off the voltage based on information acquired by the detection mechanism. The electrophoresis apparatus according to claim 1,
The electrophoretic device in which the power supply mechanism cuts off the voltage based on a change rate of the current value. The electrophoresis apparatus according to claim 2, wherein
The electrophoretic device, wherein the power supply mechanism cuts off the voltage when a rate of change of the current value becomes a predetermined value or more. The electrophoresis apparatus according to claim 3, wherein
An electrophoresis apparatus capable of setting the predetermined value based on a capillary length, the number of capillaries, a separation medium type, and / or a measurement technique. The electrophoresis apparatus according to claim 1,
The electrophoretic device, wherein the power supply mechanism cuts off the voltage when the current value reaches a predetermined value. The electrophoresis apparatus according to claim 1,
An electrophoretic device that does not block the voltage based on information acquired by the detection mechanism when the power supply mechanism changes voltage. The electrophoresis apparatus according to claim 1,
The electrophoretic device, wherein the power supply mechanism cuts off the voltage when bubbles are generated in the separation medium. The electrophoresis apparatus according to claim 1, comprising:
(6) An information transmission mechanism for notifying that bubbles have occurred in the separation medium based on information acquired by the detection mechanism. A method of electrophoresis using a capillary, comprising the following steps;
(1) A procedure for detecting a current value flowing through a separation medium during electrophoresis;
(2) A procedure for stopping electrophoresis based on the current value. The electrophoresis method according to claim 9, comprising:
The method (2) is a “procedure for stopping electrophoresis when the rate of change in current value exceeds a predetermined value”. The electrophoresis method according to claim 9, comprising:
The method (2) is “a procedure for calculating an average value of current values for a predetermined time and stopping electrophoresis when a change rate of the average value is equal to or greater than a predetermined value”. The electrophoresis method according to claim 9, comprising:
The method (2) is a “procedure for stopping electrophoresis when the current value becomes a predetermined value or less”. The electrophoresis method according to claim 10, comprising:
A method of setting the predetermined value based on a capillary length, the number of capillaries, a separation type, and / or a measurement technique. An electrophoresis apparatus comprising the following configuration;
(1) One or more capillaries that are filled with a separation medium that separates a sample, and that include an introduction end portion into which the sample is introduced and a light irradiation portion that is irradiated with light;
(2) Excitation optical mechanism for irradiating light to the light irradiation unit;
(3) a light receiving optical mechanism for detecting light emitted from the light irradiation unit;
(4) a detection mechanism for acquiring information depending on the current flowing in the current path;
(5) A power supply mechanism that applies a voltage to the energization path including at least the introduction end and the light irradiation unit;
(6) A notification mechanism that notifies the state of the energization path based on the current flowing through the energization path when the predetermined voltage is applied. The electrophoresis apparatus according to claim 14, wherein
An electrophoretic device that informs that the state of the energization path is inappropriate for electrophoresis when the notification mechanism has a current smaller than a predetermined value. The electrophoresis apparatus according to claim 14, wherein
The electrophoresis apparatus, wherein the predetermined voltage is smaller than a voltage at which discharge occurs when the capillary is not filled with a separation medium. The electrophoresis apparatus according to claim 14, comprising the following configuration;
(7) A buffer solution container that holds a buffer solution that becomes a part of the current path;
The electrophoresis apparatus, wherein the predetermined voltage is smaller than a voltage at which discharge occurs when the buffer container is not filled with the predetermined buffer. An electrophoresis method using a capillary including the following procedure;
(1) Procedure for filling the capillary with the separation medium (2) Prior to the electrophoresis of the sample, a voltage smaller than the voltage for electrophoresis of the sample is applied to the energization path including the separation medium, and the current flows through the energization path Procedure for detecting current (3) A procedure for determining the state of the energization path based on the detected current. The electrophoresis method according to claim 18, comprising:
The method (3) is “a procedure for determining that the energization path is unsuitable for electrophoresis when the detected current is smaller than a predetermined value”. The electrophoresis method according to claim 18, comprising:
A method in which the voltage is smaller than the voltage at which a discharge occurs when the capillary is not filled with a separation medium or / and there is no appropriate amount of buffer in a buffer container holding a buffer that is part of the current path.

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