JPH05180820A - Solvent mixing column - Google Patents

Abstract

PURPOSE:To carry out gradient analysis at high accuracy by providing an element rotated by external induction, in a column, which has inflow and outflow parts for a solvent, and in which the inner capacity can be varied. CONSTITUTION:An element 5 rotated by external induction is provided in a column for chromatography of high speed liquid, which is provided with an inflow part l and an outflow part 2 for a solvent, and in which the inner capacity can be changed by a screw 3. The element 5 is rotated while gradient analysis is carried out, and the solution therein is stirred, and a homogeneously mixed liquid is thus provided. The inner capacity is varied as required by rotating the screw 3. After the column is filled with the solvent, a valve is replaced, and a solvent of the composition different from that is filled in the column is make to flow therein. The solvent is stirred sufficiently by the rotating element 5, and the solvent flows out of the column while the composition is being changed, and the solvent is sent to the analysis column filled with a filler of various characteristics. The gradient of the column can be changed by changing the inner capacity of the column.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solvent mixing column for analyzing a target component with high accuracy in analysis using high performance liquid chromatography.

[0002]

2. Description of the Related Art In recent years, high performance liquid chromatography has been widely used for qualitative, quantitative analysis or separation of various substances. Although various separation methods by high performance liquid chromatography are known, a gradient method is often used for separating multiple components. This method is a method in which the composition ratio of two or more different solvents is sequentially changed over time and is sent to a separation column, but conventionally, two or more pumps separately send the solvent, or a special solvent is used. A different solvent mixing device was required.

Further, with the recent widespread use of microcolumns, it has become possible to analyze a small amount of sample. However, since the amount of liquid sent to the microcolumn is generally extremely small, it is very accurate for performing gradient analysis. I needed more than one good pump.

[0004]

The conventional method requires two or more expensive liquid-sending pumps, and also a computer for controlling each pump, which is very complicated. It was a device. In addition, when performing gradient analysis using a microcolumn, it is necessary to accurately deliver several μl / ml with each pump, but at present it is almost impossible, and the composition ratio of the solvent is accurate. So delicate control was very difficult.

[0005]

SUMMARY OF THE INVENTION The present invention is a column for high performance liquid chromatography having a device having an inflow part and an outflow part of a solvent and capable of changing the internal volume, and having an element rotating by induction from the outside. is there. More specifically, in the column (4) having the solvent inflow portion (1) and the solvent outflow portion (2), the inner volume of which can be changed by the screw (3), the element (5) rotating by induction from the outside ) Is a column for high performance liquid chromatography.

When the column according to the present invention is connected to a high performance liquid chromatography, a gradient method which has been complicated in the past can be performed very easily and inexpensively. It is an object of the present invention to provide a solvent mixing column which enables this simple and inexpensive gradient method.

Since the column according to the present invention needs to withstand a high-pressure solvent containing various salts, it is preferably made of a corrosion-resistant and pressure-resistant metal such as stainless steel. This column is provided with at least one solvent inflow part and one outflow part, and a normal high performance liquid chromatography is connected to this part. In order to prevent bubbles generated during the gradient analysis from staying in the column, the solvent inflow part is usually at the bottom of the column and the outflow part is at the top of the column, but it is not particularly limited. For the same reason, when the outflow portion is located at the upper part of the column, the bottom surface of the screw (3) is preferably concave downward. The column contains a rotating element by induction from the outside, and it can be rotated during the gradient analysis to stir the internal solution to form a uniform mixed solution. A homogeneous mixed solution can be obtained by a method capable of stirring the internal solution other than the rotating element, for example, a method of irradiating ultrasonic waves from the outside.

One of the features of the column according to the present invention is that
The point is that the internal volume of the column can be changed. That is, the inner volume can be arbitrarily changed by turning the inner volume adjusting screw (3) in FIG. The internal volume also varies with the diameter of the column. The internal volume is usually 20 μl to 100 ml, preferably 50
μl to 50 ml. A scale or the like can be attached to the screw or the like so that the amount of the internal volume can be known depending on the position of the internal volume adjusting screw. To change the internal volume, rotate the screw manually, but the motor
It is also possible to connect a driving device such as. Further, other than the screw, the object of the present invention can be achieved as long as it is a method of withstanding high pressure and changing the internal volume.

The column according to the present invention can be used by connecting to a conventionally used high performance liquid chromatography system. Although a detailed experimental example will be described later, after the column is filled with the solvent, the bubbles are switched and a solvent having a composition different from that of the solvent filled in the column is flowed. Since the rotor is rotating inside the column, the solvent is sufficiently stirred, the composition thereof is gradually changed, and the solvent flows out from the column and is sent to the analytical column packed with the packing material having various properties.
The rate of change of the solvent composition, that is, the gradient of the gradient depends on the liquid feed amount and the volume of the column according to the present invention, but controlling the liquid feed amount is limited. Therefore, changing the gradient of the gradient by changing the internal volume of the column according to the present invention is very useful for setting the analysis conditions.

[0010]

[Effect] By using the solvent mixing column according to the present invention, it becomes possible to perform gradient analysis with one pump, which conventionally required two or more liquid feed pumps. That is, by using a syringe or the like, a solvent having a different composition is caused to flow into a column filled with a solvent in advance by a feed pump, sufficiently mixed in the column, and then fed to an analytical column, which enables gradient analysis. .. By using this column, it is possible to perform a reproducible gradient analysis even with the liquid feed amount at the constant flow rate limit of the pump. Of course, more complicated gradient analysis can be performed by connecting two or more pumps. Furthermore, since the inner volume of the column can be changed, the gradient of the gradient can be changed arbitrarily, and the analysis conditions can be set very easily when analyzing many types of samples.

[Experimental Example] An experimental example using the column according to the present invention will be described below. As shown in FIG. 2, the column (8) according to the present invention was connected between the hexagonal valve and the sampling loop. The solvent is injected from the injection part (9) using a syringe or the like, and the column (8) and the sampling loop (7) are injected.
Was filled with solvent. Acetonitrile: water (1
The mixed solution of 5:85) was used. Next, the sample solution in which the sample was dissolved was injected. In this state, the pump (1
0) may be stopped or the solvent may be allowed to flow. Pump (10) and analytical column (11) for solvent flow
And through the detector (12).

Next, switching the hexagonal valve results in FIG. The solvent (13) different from the solvent filled in the column (8) according to the present invention is sent by the pump (10). The solvent was thoroughly mixed and stirred in the column (8) according to the present invention, and the sampling loop (7) and the analytical column (11) were mixed.
And discharged through the detector (12). The sample is separated by the analytical column (11) and detected by the detector (12).

The solvent sent here is mixed and stirred with a different solvent in (8), so that the composition thereof is successively changed when flowing out from (8). That is, in the initial stage, most of the solvent filled with (8) flows out, but the ratio of the new solvent increases successively, and finally only the new solvent flows out. The capacity of the column according to the present invention is 130, 28
Chromatograms when 0,630 μl are shown in FIGS.
It was shown to. Samples are methyl benzoate, ethyl benzoate,
A solution of n-propyl benzoate, n-butyl benzoate, n-heptyl benzoate and n-octyl benzoate dissolved in methanol was used. Injection volume of each sample is 100-500
ng.

High performance liquid chromatography conditions were set as follows. Column: Inertsil ODS-2 (2.1 x 250 mm) Mobile phase: Acetonitrile: Ethanol (1: 1) Detection: UV254 nm Flow rate: 100 μl / min

As is clear from FIGS. 4 to 6, by changing the capacity of the solvent mixing column (8), the retention time of each sample is lengthened and the resolution is improved. Moreover, each peak was extremely sharp even if the holding time was long. Furthermore, the variation of the base line that occurs in the conventional gradient method was not observed, and a very clean chromatogram was obtained.

[0016]

[Brief description of drawings]

FIG. 1 shows a sectional view of a solvent mixing column according to the present invention. FIG. 2 shows a high performance liquid chromatography system in which a solvent mixing column according to the present invention is connected to a high performance liquid chromatography, the solvent mixing column is filled with a solvent, and a sample solution is injected. FIG. 3 shows a high performance liquid chromatography system in which a solvent mixing column according to the present invention is connected to a high performance liquid chromatography, a solvent having a composition different from that of the solvent mixing column is fed, and a gradient analysis is performed. FIG. 4 shows the capacity of the solvent mixing column according to the present invention.
The chromatogram when μl is shown. FIG. 5 shows the capacity of the solvent mixing column according to the present invention of 280.
The chromatogram when μl is shown. FIG. 6 shows the capacity of the solvent mixing column according to the present invention as 630.
The chromatogram when μl is shown.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Yoshida 4-5-18 Honjo, Honjo City, Saitama Prefecture (72) Inventor Tadashi Sato 7-20-10 Tsukushino, Abiko City, Chiba Prefecture

Claims (4)

[Claims] 1. A column for high performance liquid chromatography, comprising a column having a solvent inflow section and a solvent outflow section, the volume of which can be changed, and an element which is rotated by induction from the outside. 2. The column for high performance liquid chromatography according to claim 1, wherein the method of changing the internal volume is a screw method. 3. A column (4) having an inflow part (1) and an outflow part (2) of a solvent, the inner volume of which can be changed by a screw (3), which is rotated by induction from the outside ( A column for high performance liquid chromatography having 5). 4. The column for high performance liquid chromatography according to claim 1, wherein the internal volume is 20 μl to 100 ml.