JPH052941B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention relates to an isotachophoresis device, and more specifically, a capillary type etc. equipped with a display section that displays the movement position of sample ions in an electrophoresis tube during sample analysis. This relates to a fast electrophoresis device.

(b) Prior Art As shown in FIG. 1, a conventional capillary type isotachophoresis apparatus has a terminal electrode tank 2 at one end of an electrophoresis tube 1, and a leading electrode via a detector 3 at the other end. Each electrode tank 4 is provided, and sample ions are migrated in the migration tube 1 from the terminal electrode tank 2 side to the leading electrode tank 4 side for separation and detection.

However, in this device, from the start of sample ion migration until the sample ions are detected by the detector 3, the detector 3 only detects the ions of the leading electrolyte, that is, the leading ions, and therefore the detection data is draws a baseline indicating a state where no sample ions are detected. Therefore,
Information such as how close the sample ion zone is to the detector 3 and how long it will take to complete the analysis of the sample during electrophoresis could not be obtained.

As a countermeasure against this, it is possible to obtain the above information by measuring in advance the increase in voltage applied between the terminal electrode 5 and the leading electrode 6 in both electrode baths and the migration time of the sample ions. This method has a problem in that the position of the tip of the sample ion zone in the migration tube 1 cannot be accurately determined because the voltage rise width and migration time vary depending on the magnitude of the migration current value.

(C) Purpose This invention is intended to enable a sample analyst to intuitively and accurately know the position of the tip of the sample ion zone in the migration tube during sample analysis.

(D) Configuration The configuration of the present invention is that a migration tube is provided with a terminal electrode tank at one end and a leading electrode tank at the other end, and a high voltage is applied to both of these electrode tanks to move the inside of the migration tube. In an isokinetic electrophoresis device in which an electrophoresis current is applied, an electrophoresis current detecting means for detecting an electrophoresis current value is provided, and an electrophoresis current is applied in an electrophoresis tube containing only a terminal and a leading electrolyte, so that the interface between both electrolytes is placed on the leading electrode side. means for storing or setting the integrated value of the detected electrophoretic current value when the sample is moved toward the boundary surface in correspondence with each position of the boundary surface; An isokinetic electrophoresis apparatus comprising a calculation means for calculating and predicting the tip position of the sample ion zone in the migration tube by comparing with the stored or set integrated value, and a display means for displaying the calculation result. .

(e) Examples This invention will be described in detail below based on examples shown in the figures. Note that the present invention is not limited thereby.

FIG. 2 is a diagram showing the overall configuration of the capillary type isotachophoresis device 7. As shown in FIG.

8 is an electrophoresis tube, and the inner diameter of this electrophoresis tube is 0.8 to 1.0 mm.
It consists of a large-diameter migration tube 9 with a diameter of φ and a small-diameter migration tube 10 with an inner diameter of 0.2 to 0.5 mmφ, and a leading electrode tank 12 is connected to this small-diameter migration tube in communication via a detector 11. At the same time, a terminal electrode tank 13 is connected to the large-diameter migration tube 9 in communication. 14
is a high voltage power supply that applies a high voltage between both electrodes 15 and 16 in both electrode tanks 12 and 13. Note that 17 is a sample injection section.

A migration current detection circuit 1 for detecting the migration current imA flowing in the migration tube 8 in turn is connected to this high voltage power supply.
8 and the electrophoresis current imA, and store the electrophoresis tube 8.
A microcomputer 19 that calculates the position of the tip of the sample ion zone 22 in the sample ion zone 22 is connected to a cathode ray tube (CRT) 20 that displays the calculation results on a display. This microcomputer is
It is connected to the detector 11 and also to a both-end voltage detection circuit 21 which is connected to the high-voltage power supply 14 in parallel with the migration current detection circuit 18 . This detection circuit is for detecting the voltage across the high voltage power supply 14.

Capillary type isotachophoresis device 7 consisting of the above configuration
The operation will be explained below.

First, without injecting a sample into the electrophoresis tube 8, that is, with only the leading electrolyte and the terminal electrolyte, a high voltage is applied to the leading electrode 15 and the terminal electrode 16, and the electrophoresis current imA is applied to the electrophoresis tube 8. flow. Then, the interface between the leading electrolyte and the terminal electrolyte begins to move from the terminal electrode tank 13 side toward the leading electrode tank 12 side. Therefore, the electrophoretic current
The electrophoretic current detection circuit 18 detects imA every moment, the detected electrophoretic current imA is integrated by the microcomputer 19, and the integrated value Q is obtained as shown in the following equation.

Q=∫i(t)dt When the boundary surface reaches A in FIG. 2, for example, if the high voltage power supply 14 is a constant current type,
Since the state of change in the voltage across the high-voltage power supply 14 is different from the normal case, the voltage detection circuit 2 detects this change.
1, and the microcomputer 19 stores Q at this time as the set integrated value Q ₁ when the boundary surface position is A. Furthermore, the boundary surface moves,
When it reaches the detector 11, the detector 11 detects this arrival signal and transmits it to the microcomputer 19, and the microcomputer 19 sets Q at this time as the set integrated value _Q2 when the boundary surface is at the position of the detector 11. memorize it.

Next, when actually analyzing a sample, the integrated value Q of the electrophoresis current from moment to moment is calculated using the set integrated value Q ₁ and
Comparing Q ₂ and the microcomputer 19, the sample zone 22 is larger than the large diameter electrophoresis tube 9.
Alternatively, the position within the small-diameter migration tube 10 is calculated and predicted.

More specifically, if Q matches Q ₁ or Q ₂ , it is predicted that the front end of the sample zone 22, that is, the rear end of the leading electrolyte, is at the position A and the detector 11, respectively. If the value is less than or equal to Q ₁ or between Q ₁ and Q ₂ , Q/Q ₁ , Q-Q ₁ /Q ₂ -
The degree of approach (position) to A or the detector 11 is predicted from the value of _Q1 .

The calculation information obtained in this way can be used, for example, as shown in FIG. CRT20 with
displayed on the screen. Figure 4 A to C show the predicted front end position of the sample zone 22, respectively.
is less than Q ₁ , that is, the predicted front end position of the sample zone ₂₂ is in the middle of the large-diameter electrophoresis tube ₉ . A case in which there are 22 predicted front end positions is shown.

By configuring the capillary isotachophoresis device 7 as described above, a sample analyst can intuitively know the tip position of the sample ion zone in the electrophoresis tube during sample analysis. Moreover, if a sample analyst leaves during an analysis and returns, he or she can easily predict how long it will take to complete the sample analysis, so he or she can do other work without wasting time. be able to. In addition, even if the inner diameters of the electrophoresis tubes are the same, the time from the start of electrophoresis to detection by the detector is investigated in advance, and this time is converted to each position of the sample ion in the electrophoresis tube and stored in the microcomputer. When the sample ion is set, the progress state of the sample ion can be displayed in the same manner as described above.

(F) Effects This invention includes a migration current detection means for detecting a migration current value, a specific calculation means, and a display means for displaying the calculation results, thereby making it possible to detect the sample in the migration tube during sample analysis. This makes it possible to intuitively and accurately know the tip position of the ion zone at all times.

[Brief explanation of the drawing]

Fig. 1 is an explanatory block diagram of a conventional capillary type isotachophoresis device, Fig. 2 is an explanatory block diagram showing an embodiment of the capillary type isotachophoresis device according to the present invention, and Fig. 3 is an explanatory block diagram of this CRT. Plan view showing the screen, Figure 4 A, B,
3 is a diagram corresponding to FIG. 3 showing the position of the tip of the sample ion zone. 7... Capillary isokinetic electrophoresis device, 8... Electrophoresis tube, 12... Leading electrode tank, 13... Terminal electrode tank, 18... Electrophoresis current detection circuit, 19
...Microcomputer, 20...CRT.

Claims (1)

[Scope of Claims] 1. A migration tube is provided with a terminal electrode tank at one end and a leading electrode tank at the other end, and a high voltage is applied to both electrode tanks to apply an electrophoresis current in the migration tube. In an isotachophoresis device, a migration current detection means for detecting the migration current value and a migration current are passed through the migration tube containing only the terminal and leading electrolytes to move the interface between the two electrolytes toward the leading electrode side. means for storing or setting the integrated value of the detected electrophoretic current value in correspondence with each position of the boundary surface; and means for sequentially integrating the detected electrophoretic current value after sample injection and storing or setting the integrated value. 1. An isotachophoresis apparatus comprising: calculation means for calculating and predicting the position of the tip of a sample ion zone in an electrophoresis tube by comparing the calculated integrated value; and display means for displaying the calculation result.