JPS6147558A - Sample introduction apparatus for liquid chromatography - Google Patents

Abstract

PURPOSE:To introduce a sample accurately and positively into a column without changing the feed of developing solution for introduction of the sample, by combining a buffer pump having two pump bodies and a specified sampling valve. CONSTITUTION:A developing solution to be fed to a first pump body 5a of a buffer pump 5 is always introduced into a side inlet 3 of a column 1 while a developing solution from a second pump body 5b is introduced into the side inlet 3 through passages 14e and 13c of a sampling valve 7. A sample is absorbed by a sample holding tube 7b with a sampling pump 10 from a pippets 9. As a rotor 7a rotates, the passage 13b aligns a channel 15d and the developing solution from the second pump body 5b is fed to introduce all the sample in the tube 7b to a central nozzle 2. In the course of switching, the developing solution from the pump body 5b flows temporarily both to the sample holding tube 7b and the side inlet 3 and thus, there is no variations in the pressure once the column is lowered free from the stoppage of the flow thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to a sample introduction device for liquid chromatography.

[Conventional technology]

BACKGROUND ART In liquid chromatography used in amino acid analyzers and the like, some devices employ a center injection method as a device for introducing a sample into a column. 6th
The figure shows sample introduction in conventional liquid chromatography! It is a system diagram showing an apparatus.

In the drawings, reference numeral 1 denotes a column, the inside of which is filled with resin, and a central nozzle 2 is connected to the upper center, a side inlet 3 is connected to the upper periphery, and an outflow pipe 4 is connected to the lower part. Reference numeral 5 denotes a (dual system) buffer pump, of which a branch pipe 6a of a discharge pipe 6 is connected to the central nozzle 2 via a sampling valve 7, and a branch pipe 6b is connected to the side inlet 3 via a resistor 8. The sampling valve 7 has a sample hold tube 7b on the rotor 7a, which is connected between the branch pipe 6a and the central nozzle 2 in one rotary position, and connected between the pipette 9 and the sampling pump 10 in the other rotation position. It is designed to be connected in between. 11 is a sample tube.

In the above configuration, the sampling valve 7 drives the sampling pump 10 in the state shown in the figure, and the sample is sucked from the sample tube 11 by the pipette 9 and introduced into the sample hold tube 7b. After sampling is completed, when the sampling valve 7 is switched to the position indicated by the broken line, the developing liquid sent from the buffer pump 5 is divided by the resistor 8, and the branch pipe 6a
The developing solution passing through introduces the sample in the sample hold tube 7b into the column 1 from the central nozzle 2, and the developing solution passing through the branch pipe 6b is introduced from the side inlet 3 to the upper periphery of the column 1 and is uniformly developed. .

[Problem that the invention seeks to solve]

In the above-mentioned conventional device, the developing liquid is dispensed by the resistor 8, so the amount of developing liquid tends to change slightly, and the tip of the central nozzle 2 is filtered with a thickness of several microns or less to prevent the resin from flowing back. However, there are problems in that injection resistance increases and injection failure occurs due to foreign matter adhering to the filter.

[Means for solving problems]

This invention is intended to solve the above problems, and by combining a buffer pump having two pump bodies and a specific sampling valve, it is possible to change the amount of the developing solution sent for inserting the sample into the center. To provide a sample introduction device for liquid chromatography that can accurately and reliably forcefully introduce a sample into a column without any problems.

The present invention is a sample introduction device for liquid chromatography that introduces a sample into a central nozzle provided at the center of the upper part of a column, and introduces a developing solution into a side inlet provided at the periphery of the upper part of the column. , a buffer pump having first and second pump bodies; a pipe for introducing the developing liquid sent from the first pump body into the side inlet; The sampling sample is introduced into the central nozzle by a developing solution sent from the second pump body, and the sampling sample is switched to introduce the developing solution sent from the second pump body into the side inlet 1- during sampling and switching. This is a liquid chromatography sample introduction device characterized by having a small number of valves.

[For production]

In the sample introduction device for liquid chromatography configured as described above, a developing solution is delivered by a buffer pump, and the developing solution delivered by the first pump body is introduced into the side inlet of the column. After sampling with the sampling valve, the sampling sample is introduced into the central nozzle of the column by the developing liquid sent from the second pump body, and the developing liquid sent from the second pump body during sampling and switching. The liquid is introduced into the side inlet of the column.

This allows the sample to be accurately and reliably forcibly introduced into the column without changing the amount of developing solution sent to introduce the sampling sample into the column.

Furthermore, the second pump body does not stop feeding liquid during sampling and switching, and noise due to pressure fluctuations does not occur.

〔Example〕

Figures 1 to 4 are system diagrams showing different operating states m of an embodiment of the present invention, Figure 5 is a perspective view of the sampling valve, and the same reference numerals as in Figure 6 indicate the same or equivalent parts. .

The buffer pump 5 is driven by a first pump main body 5 by a driving section.
a and a pump that operates the second pump body 5b,
The suction side is connected to the same developing liquid supply source, and the same high-pressure constant-flow dual plunger pump as the conventional one can be used. The discharge side of the first pump body 5a is connected to the side inlet 1-3 of the column 1 through a pipe 12'a, and the discharge side of the second pump body 5b is connected to the stator 7c of the sampling valve 7 through a pipe 12b. ing.

The sampling valve 7 is mounted on the rotor 7 below the stator 7c.
a repeats rotation by an angle α. The rotor 7a has an axial passage 13a on the same circumference from the sliding surface 7d to the lower end surface 7e.

13b and 13c are provided, and a flow path 13a.

A sample hold tube 7b is connected between the lower ends of the flow path 13b, and the lower end of the flow path 13c is connected to the side inlet 1-3 by a pipe 12c.

The stator 7c has an axial passage 14a extending from the upper end surface 7f to the sliding surface 7d on the same circumference as described above.

14b, 14c, 14d and a flow path 14e branched in an inclined direction from the upper end of the flow path 14d.
Grooves 15b, 15d extending to the right on the same circumference from the lower ends of the channels 4b, 14cl, and a groove 15e extending in the opposite direction from the flow path 14e are formed. The upper end of the flow path 14a is connected to the pipette 9, the upper end of the flow path 14b is connected to the central nozzle 2 via the pipe 12d, the upper end of the flow path 14c is connected to the sampling pump 10, and the upper ends of the flow paths 14d and 14e are connected. are joined together and connected to the second pump main body 5b via a pipe 12b. In addition, when the rotor 7a rotates, the lower ends of the channels 14a to 14e and the grooves 15b, ISd, and 15e
It coincides with the upper ends of the channels 13a to 13c.

In the sample introduction device for liquid chromatography configured as described above, when performing an analysis, the buffer pump 5 is driven and the first and second pump bodies 5a, 5b are
The developing solution is fed from the same developing solution supply source. Among these, the developing liquid sent by the first pump main body 5a is always introduced into the side inlet 3 of the column 1 from the piping 12a.

The developing liquid sent by the second pump main body 5b is supplied to the pipe 1
2b to the sampling valve 7.

In the sampling valve 7, the rotor 7a repeats rotation by an angle α from the A position to the B position, and is switched to perform sampling and sample introduction.

First, the rotor 7a starts rotating in the direction of the arrow from position A in FIG. 5, and the force is in the state shown in FIG. 1 and FIG.

At this time, the channels 13a and 14a, the channels 13b and 14c, and the channel 13c and the groove 15e match, and the sampling pump 1o
The sample is sucked into the sample hold tube 7b from the pipette 9 and sampling is performed, and the developing liquid from the second pump main body 5b is transferred from the flow paths 14e and 13c to the pipe 1.
2c and is inserted into the side inlet 1-3.

When the rotor 7a rotates to the state shown in Fig. 2, the valves at both ends of the sample hold tube 7b are cut and sampling ends, but the developing liquid in the second pump main body 5b continues to flow into the side inlets 1 to 3. be introduced. When the rotor 7a further rotates 11i, the state shown in FIG. 3 is reached, and the flow paths 13a and 14b, the flow paths 13b and 14d, and the flow paths 13c and 14e are aligned, and the liquid is delivered from the second pump body 5b. Part of the liquid is introduced into the sand inlet 3 through the channels 14e and 13c, and part of the liquid is pushed out from the channels 14d and 13b to push out the sample in the sample hold tube 7b. Start the operation to introduce the

When the rotor 7a further rotates, the flow path 1 as shown in FIG.
3c and 14a are blocked, and the flow path 13a and groove 15b are aligned, and the flow path 13b and groove 15d are aligned, and all the developing liquid sent from the second pump body introduces the sample in the sample hold tube 7b into the central nozzle 2. The liquid is delivered as follows. The switching from the state shown in FIG. 1 to the state shown in FIG. 4 is instantaneous and is a single step, but during the switching, the developing liquid from the second pump main body 5b is temporarily transferred to the sample hold tube 7b. Flows to both side inlets 3.

Since there is no stoppage of liquid feeding, pressure fluctuations after the column do not occur.

In the state shown in FIG. 4, the developing liquid from the second pump main body 5b flows only into the sample hold tube 7b, and the sample is forcibly introduced into the central nozzle 2, and is not affected by pressure fluctuations in other systems. Sample injection is performed accurately and reliably even when the injection resistance of the filter increases. During this time, the developing liquid is introduced from the first pump main body 5a to the side inlet 3, and is developed in the collar lz1.

After the injection is completed, the rotor 7a reverses from the B position to the A position, performs sampling in the state shown in FIG. 1, and waits.

In the above device, the sample in the sample hold tube 7b can be forcibly injected into the column 1 by an independent flow system, so it can be introduced accurately and reliably into the column 1 without being affected by other flow systems. can. Further, by using the sampling valve 7, stable injection can be performed without stopping the flow of the developing liquid in the second pump main body 5b and without increasing the number of valves. Furthermore, the entire sample can be continuously injected without dividing the bulb-cut sample.

In addition, in the above description, the sampling valve 7 refers to the second pump main body 5b after sampling.
The sampling sample is introduced into the center nozzle of the column 1 by the developing solution sent from the pump main body 5b, and the developing solution sent from the second pump main body 5b is introduced into the side inlet 3 during sampling and switching. It may be of any type as long as it does not interrupt the liquid, and is not limited to what is shown.

〔Effect of the invention〕

According to the present invention, by combining a buffer pump having a second pump body and a specific sampling valve, the sample can be accurately and reliably delivered without changing the flow rate of the JJIL open liquid for introducing the sample. It can be forcibly introduced into the column, and there is no noise due to pressure fluctuations or sample division, allowing for highly accurate analysis.

[Brief explanation of the drawing]

1 to 4 are system diagrams showing different operating states of an embodiment of the present invention, FIG. 5 is a perspective view of a sampling valve, and FIG. 6 is a system diagram of a conventional device. In each figure, the same reference numerals indicate the same or equivalent parts, 1 is the column, 2 is the central nozzle, 3 is the side inlet, 5 is the buffer pump, 5a is the first pump body, 5b is the second pump body, 7 is the sampling valve, 7a is the rotor,
7b is a sample hold tube, 7c is a stator, 7
d is the sliding surface, 9 is the pivot 1~. 10 is a sampling pump, 12a to 12d are piping, 13a to 13c, 14a"
14e is a flow path, and 15b, 15d, and 15e are grooves.

Claims (4)

[Claims] (1) In a sample introduction device for liquid chromatography, which introduces a sample into a central nozzle provided in the upper central part of the column and a developing solution into a side inlet provided in the upper peripheral part of the column, the first and a buffer pump having a second pump main body; a pipe for introducing the developing solution sent from the first pump main body into the side inlet; A sampling valve that introduces the sampling sample into the central nozzle using a developing solution, and switches to introduce the developing solution sent from the second pump body into the side inlet during sampling and switching. Characteristic sample introduction device for liquid chromatography. (2) a rotor in which the sampling valve has a flow path connected to both sides of the sample hold tube and a flow path connected to the side inlet; and a flow path connected to the pipette;
The stator has a flow path connected to the central nozzle, a flow path connected to the sampling valve, and a stator having two flow paths connected to the second pump body, and the respective flow paths are sequentially connected by rotation of the rotor. The sample introduction device for liquid chromatography according to claim 1, which is switchable. (3) The sample introduction device for liquid chromatography according to claim 2, wherein the flow path connected to the central nozzle and the flow path connected to the second pump body have grooves on the sliding surface with the rotor. . (4) The sample introduction device for liquid chromatography according to any one of claims 1 to 3, wherein the buffer pump is a double plunger pump.