JP2932639B2 - Liquid supply device for capillary electrophoresis device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for supplying a sample, an electrolytic solution, a washing solution and the like in a capillary electrophoresis device.

(Prior art) In capillary electrophoresis, a capillary having an inner diameter of about 100 μm is filled with an electrolytic solution, a sample is injected into one end of the capillary, a voltage is applied between both ends of the capillary, and sample components are separated from each other by electrophoresis. Things.

This method has the advantage that a very small amount (a few nl) of the sample is sufficient, and is suitable for the analysis of a very small amount of sample.

In the apparatus for performing the above-described capillary electrophoresis, in order to fill the above-described various liquids into the capillary tube, usually, one end of the capillary tube is inserted downward into a liquid container of the above-described various liquids, and the inside of the tube is inserted. The liquid is sucked.

At this time, when the filling of one liquid is completed and the lower end of the capillary is pulled up from the liquid level in the container of the liquid, the liquid in the container adheres to the lower end of the tube in the form of droplets. The following problems arise from this phenomenon.

(1) If the liquid sucked into the capillary is an electrolytic solution, and the liquid droplets adhere to the lower end of the tube, and then insert the tube into the sample container, this analytical method is originally suitable for microanalysis.
Since there is only a small amount of the sample, the concentration of the sample is diluted by the droplet of the electrolyte, and it is difficult to obtain quantitative data.

(2) After the sample is sucked into the capillary, when the tube end is inserted into the electrolytic solution, a part of a small amount of the sample is taken out as droplets attached to the tube end and discarded in the electrolytic solution. Loss of valuable sample. The problem that the sample is mixed in the electrolyte may not be a problem because the amount of the electrolyte in the container is much larger than that of the sample.

In the conventional capillary electrophoresis apparatus, no aggressive measures have been taken against the above-mentioned problems (1) and (2), and only the liquid at the end of the tube is manually sucked and removed. In this way, sample dilution was prevented, but sample loss was not avoided.

(Problems to be Solved by the Invention) An object of the present invention is to provide a liquid supply device capable of removing droplets adhering to a capillary tube when supplying various liquids to a capillary electrophoresis device. is there.

(Means for Solving the Problems) Means for vertically moving and horizontally moving relatively between the lower end of the capillary tube and the supply liquid container, and inserting the lower end of the capillary tube into the liquid in the container, and then performing the capillary operation The lower end of the capillary is separated from the liquid surface in the container, and in this state, the capillary and the container are moved horizontally in one direction by a predetermined distance, and in this state, the lower end of the capillary and the container further close the mouth of the container. The container was moved up and down in a direction in which it did not come out, and then the horizontal position of the container and the capillary was returned to the original position, and the means was driven so that the lower end of the capillary was pulled out of the mouth of the container.

Further, the containers of the above-mentioned various solutions were made to be able to be centrifuged.

(Operation) The operation will now be described assuming that the container is moved vertically and horizontally. Raise the container so that the lower end of the capillary enters the liquid level in the container. In this state, the solution can be sucked into the capillary. Next, the container is lowered and the lower end of the capillary is brought out from the liquid surface. At this time, a droplet is attached to the lower end of the tube. Next, when the container is moved horizontally a certain distance, the middle of the capillary is pushed against the rim of the container, the lower end of the capillary is bent, and the lower end contacts the inner surface of the container. When the container is lowered in this state, the lower end of the capillary rises up the inner surface of the container while being in contact with the inner surface of the container. During this time, the liquid droplets attached to the lower end of the capillary are transferred to the inner surface of the container, and the solution is drawn vertically to the inner surface of the container. The droplets adhering to the lower end of the capillary flow down the wet strip and flow down, so that the droplets adhering to the lower end of the capillary are removed and returned to the liquid in the original container. afterwards,
When the container is returned to the original position in the horizontal direction and lowered, the lower end of the capillary can be taken out of the mouth of the container, and no liquid drops remain at the lower end of the capillary.

Further, if the container is placed in a form that can be centrifuged, the solution applied to the inner surface of the container as described above can be quickly centrifuged into the liquid in the original container. Can be returned to.

(Embodiment) FIG. 1 shows an embodiment of the present invention. In the figure, reference numeral 1 denotes a column, and a lateral arm 2 is held so as to be slidable up and down. A pinion 21 that meshes with the rack 11 on the side of the column 1 is pivotally attached to the lateral arm 2, and this pinion is driven by a motor 22 attached to the lateral arm 2. An arm 3 attached to the upper part of the column 1 holds a capillary tube 4 and an air supply tube 5 for pushing the solution. 6
Is a sealing plate below the arm 3 and through which the capillary tube 4 and the air supply tube 5 penetrate. When the arm 2 is raised by holding the container 7 on the lateral arm 2, the lower end of the capillary tube 4 is inserted into the liquid in the container 7, and when further raised, the sealing plate 6 comes into contact with the mouth end of the container 7, 7. Close airtightly. When the inside of the container is pressurized by sending air from the air supply pipe 5, the liquid in the container 7 is pushed into the capillary 4. The length of the capillary projecting downward from the sealing plate 6 is such that the lower end of the capillary reaches the bottom of the container 7 when the sealing plate 6 comes into contact with the mouth end of the container 7. A limit switch 81 is attached to the column 1 so that the horizontal arm 2 hits the limit switch so that the raising of the horizontal arm 2 stops. A finger 23 gripping the container 7 on the arm 2 can be manually slid in a horizontal direction on the arm 2 between the contact 24 at the base of the arm and the contact 25 at the tip of the arm. In the position, the tube axis of the capillary tube 4 and the center line of the container 7 match. When the finger 23 is moved to a position where the mouth end thereof is slightly lower than the sealing plate 6 and the finger 23 hits the tip of the lateral arm 2, the sealing plate 6 of the capillary tube 4 is moved as shown in FIG.
A part of the lower part of the container 7 is elastically pushed and bent against the rim of the container 7 so that the capillary is pressed against the inner surface of the container 7. When the container 7 is further lowered in this state, the lower end of the capillary tube 4 moves upward by rubbing the inner surface of the container 7, and during this time, the liquid droplets adhering to the tube end are removed from the container 7 as described in the operation section. 7 Transfer to the inner surface. When the container 7 has been lowered to a certain place, the finger 23 is returned to the contact 24 at the base of the horizontal arm 2 and the horizontal arm 2 is lowered to a position where the container rests on the support substrate 13,
Release the finger 23 to remove the container 7 and replace it with the container containing the next liquid. By exchanging the container while the container is placed on the substrate 13, the height position at which the container is grasped by the finger 23 is determined. Finger 23
Is closed by a spring and can be manually opened to replace the container. The lower arm of the capillary is brought into contact with the inner surface of the container at the lowermost position and the middle of the horizontal arm 2 described above, and the horizontal arm 2 is stopped at two upper and lower positions for moving the lower end of the capillary so as to rub the inner surface of the container in that state. Limit switch 8
2,83,84 are provided.

The motor 22 is driven by the following sequence. At first, the lateral arm 2 hits the limit switch 84, and in this state, the motor 22 is switched to the normal rotation. Then, when the motor-on switch is manually pressed, the motor 22 rotates forward and the arm 2 rises, and when the arm 22 comes into contact with the limit switch 81, the motor 22 is stopped and switched to the reverse rotation. Next, when the motor-on switch is manually pressed again, the motor rotates in the reverse direction and the arm 2 descends, hitting the limit switch 82 and stopping the motor 22. Next, when the motor-on switch is pressed again, the motor 22 rotates in the reverse direction and stops when the arm 2 hits the down limit switch 83. When the motor-on switch is further pressed, the motor continues to rotate in the reverse direction and the arm 2 descends, hits the limit switch 84, and the motor 22 switches to normal rotation and stops. This completes one cycle of the vertical movement of the arm 2.
In this embodiment, all re-operations after the motor is stopped are manually performed, and before the re-operation, horizontal movement of the finger 23 for exchanging the container, operating the air supply, and removing the droplets attached to the lower end of the capillary tube is performed. And so on.

Although the above-described embodiment is manual, the operations such as the vertical movement of the horizontal arm 2, the horizontal movement of the finger 23, and the air supply for press-fitting the liquid in the container into the capillary are performed under a fixed time schedule. It is easy to perform the operation automatically, and the opening and closing of the finger 23 and the replacement of the container can be automated.

If the container 7 is placed in a form that can be applied to a centrifuge, the liquid attached to the lower end of the capillary is attached to the inner surface of the container, and then the liquid can be quickly and completely collected at the bottom of the container.

(Effects of the Invention) According to the present invention, in capillary electrophoresis analysis, loss of a sample having a small volume is prevented, dilution with other liquids is prevented, and quantitative accuracy in analysis of effective use of a small amount of sample is prevented. The effect of improvement is obtained.

[Brief description of the drawings]

FIG. 1 is a side view of an apparatus according to an embodiment of the present invention, and FIG. 2 is an explanatory view of the operation of the apparatus. DESCRIPTION OF SYMBOLS 1 ... Prop, 2 ... Side arm, 4 ... Capillary tube, 5 ... Air supply tube, 6 ... Sealing plate, 7 ... Container, 11 ... Rack, 12 ... Substrate, 21 ... Pinion, 22 ... Motor, 23 ... Finger holding the container , 81-84 ... limit switch.

Claims (2)

(57) [Claims] 1. A means for vertically moving and horizontally moving between a lower end of a capillary and a supply liquid container, and a method of inserting the lower end of the capillary into a liquid in the container, and thereafter, connecting the lower end of the capillary to the container. The inner liquid surface is separated, and in this state, the capillaries and the container are horizontally moved by a predetermined distance in one direction, and in this state, the capillaries and the container are further moved so that the lower end of the capillary does not come out of the mouth of the container. And moving the container in a direction away from the top and bottom, and then returning the horizontal position of the container and the capillary to drive the above means so that the lower end of the capillary is pulled out of the mouth of the container. Liquid supply device for electrophoresis device. 2. The liquid supply device for a capillary electrophoresis device according to claim 1, wherein the containers for the various solutions can be centrifuged.