JP2011085434A - Eluate and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide eluate for generating a deaerated state and maintaining the state for a long time. <P>SOLUTION: The eluate is manufactured by a process of filling the eluate while including a head space in an airtight, flexible vessel including at least one openable/closable opening; a process of substituting an inert gas for the head space; and a process of closing the openable/closable opening. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an eluent capable of maintaining a deaerated state for a long time, and a method for producing the same.

  As shown in FIG. 1, the liquid chromatograph includes an eluent 1, a liquid feed pump 2, a sample introduction device 3, a separation column 4, a detector 5, a control device, and the like.

  The separation column 4 is appropriately selected from a reverse phase column, a normal phase column, an ion exchange column, a size exclusion column, and the like depending on the properties of an object or impurities to be separated using a liquid chromatograph. The eluent 1 is selected according to the nature of the object to be separated and the impurities and the type of separation column 4 to be used. Usually, the eluent 1 is prepared by adding an acid, a base, a salt, a saccharide or the like to water, an organic solvent, or a water / organic solvent mixture.

  In the liquid chromatograph, a pressure of several tens of MPa is applied to the eluent 1 to send it to the separation column 4, and therefore a high-pressure liquid feed pump comprising a ball check valve and a plunger is used as the liquid feed pump 2. If bubbles derived from the gas dissolved in 1 enter the pump main body or the check valve, or bubbles are generated in the pump main body or the check valve, the liquid supply of the eluent 1 is stopped and the flow rate is changed. In addition, when bubbles enter the cells of the detector 5 or bubbles are generated in the cells, it causes noise. In order to solve the problem, the eluent 1 needs to be deaerated before being sucked into the liquid feed pump 2.

As a method for degassing the eluent,
(1) A method of removing gas by passing an eluent through the inside of a tube made of a material such as polytetrafluoroethylene (PTFE) that is easy to pass gas and difficult to pass liquid, and pulling the outside of the tube under reduced pressure or vacuum. (Vacuum degasser),
(2) A method of removing gas by stirring the eluent contained in the eluent container while heating it to near the boiling point,
(3) A method of removing gas by applying ultrasonic waves or reducing pressure while applying ultrasonic waves,
(4) A method of removing gas by reducing pressure while stirring,
(5) A method of replacing a gas dissolved in the eluent with an inert gas by bubbling an inert gas such as helium in the eluent (Patent Documents 1 and 2),
and so on. The method (1) is widely used as a degassing device for liquid chromatographs because it can be used online, but requires a dedicated degassing device consisting of a vacuum source and a vacuum chamber, and elution in the tube. Since it takes time until the liquid is replaced, there is a problem that it takes time until the analysis is stabilized. Method (2) requires agitation because it takes time to reach vapor-liquid equilibrium only by heating, and is applicable to eluents that contain highly volatile solvents or substances that are easily decomposed by heat. There is a problem that it is difficult to do. The method (3) requires a vacuum generation source and an ultrasonic bath, and has a problem of noise derived from ultrasonic waves. The method (4) also requires a vacuum generation source as in the methods (1) and (3). The method (5) is a method that does not require a special device such as a vacuum generation source. However, since the inert gas is replaced by bubbling, it is difficult to apply to an eluent containing a highly volatile solvent. Expensive helium needs to flow constantly, which is problematic in terms of cost.

  Furthermore, the methods (2) to (4) have a problem that the degassing effect is lowered because the gas dissolves again in the eluent as time elapses even after degassing. Also, in the methods (1) and (5), which can stably obtain a degassed eluent, a device that constantly bubbles a vacuum generation source or an inert gas while the degassed eluent is required. Need to be running.

  As a method for solving the problem in the degassing method, there is a method (Patent Document 3) in which an eluent degassed in advance by any one of the above methods is filled in a vacuum package state (Patent Document 3). Even if the device for maintaining the deaeration state is not operated, the deaeration state of the eluent can be maintained. However, even with this method, it is difficult to completely remove the air in the flexible container, and if air remains in the container at the time of filling, there is a problem that the remaining air is dissolved in the eluent. there were.

Japanese Examined Patent Publication No. 6-011392 Japanese Patent Laid-Open No. 9-127079 JP-A-10-082773

  An object of the present invention is to provide an eluent capable of producing a deaerated state and maintaining the state for a long time, and a method for producing the same.

  The present invention made in view of the above problems includes the following inventions.

  According to a first aspect of the present invention, an airtight flexible container having at least one opening that can be opened and closed is filled with a headspace, and an inert gas is filled in the headspace. The eluent is filled.

  A second invention is the eluent according to the first invention, wherein the inert gas is helium or neon.

The third invention is
Filling the eluent with a head space in an airtight flexible container provided with at least one opening that can be opened and closed;
Replacing the headspace with an inert gas;
Closing the opening;
An eluent production method comprising:

  A fourth invention is the manufacturing method according to the third invention, wherein the step of replacing the head space with an inert gas is a step of introducing and replacing the inert gas into the head space.

  A fifth invention is the manufacturing method according to the third invention, wherein the step of replacing the head space with an inert gas is a step of replacing the head space by bubbling the inert gas.

  A sixth invention is the production method according to any one of the third to fifth inventions, wherein the inert gas is helium or neon.

  Hereinafter, the present invention will be described in detail.

  The flexible container used in the eluent of the present invention may be provided with at least one openable / closable opening for introducing and discharging the eluent and the inert gas. When the eluent of the present invention is provided in a liquid chromatograph device, if one of the openable and closable openings is an opening that can be airtightly connected to a pipe communicating with the liquid feeding pump of the liquid chromatograph device, Even in the analysis, it is preferable in that the deaerated state of the eluent can be maintained for a long time. Further, an inert gas inlet and / or an inert gas outlet and / or an eluent inlet may be provided separately from the opening. When a plurality of openings that can be opened and closed are provided, the openings that are not used may be sealed with caps or cocks so as not to communicate with the outside air.

  The material of the flexible container used in the eluent of the present invention may be any material that has airtightness that does not transmit outside air and is not reactive with the eluent. For example, glycohemoglobin manufactured by Tosoh Corporation A resin film sandwiched between aluminum, which is a flexible container used in the eluent for the analyzer HLC-723G8.

  The size of the flexible container used in the eluent of the present invention may be appropriately selected in consideration of the amount of liquid to be fed and the continuous analysis time, but is usually selected in the range of 500 mL to 2 L.

  The inert gas that fills the head space with the eluent of the present invention is preferably a gas that is not reactive with the eluent, has a low solubility in the eluent, and has a low temperature dependency of the solubility. Neon is preferred. When helium is bubbled into the eluent, the partial pressure of oxygen and nitrogen in the bubbles is lower than atmospheric pressure, so oxygen and nitrogen dissolved in the eluent migrate into the bubbled helium bubbles, Since the partial pressure of helium is close to 1 atm, helium dissolves in the eluent. The solubility of helium in water is 1/4 to 1/2 that of oxygen and nitrogen, and the temperature dependence of the solubility is small, so bubbles are not easily generated even if the pressure is reduced or the temperature rises in the pump. . Neon, like helium, has a low solubility in water, so it is somewhat expensive but can be used as an alternative gas for helium.

  One embodiment of the eluent 10 of the present invention is shown in FIG. An opening 12 is provided on one side of the flexible container 11 so that an inert gas can be introduced / discharged, an eluent can be introduced, and a pipe communicating with the liquid feeding pump of the liquid chromatograph apparatus can be connected in an airtight manner. The opening 12 can be opened and closed by a cap 13 or a cock (FIG. 2 shows an example in which the opening is opened and closed by the cap 13).

  Another embodiment of the eluent 10 of the present invention is shown in FIGS. An inert gas inlet 12b, an inert gas outlet 12c, and an eluent that can be introduced into one side of the flexible container 11 and an opening that can be hermetically connected to a pipe that communicates with a liquid feeding pump of a liquid chromatograph Each of the openings can be opened and closed by the cap 13 or the cock 14 (FIG. 3 shows an example of opening and closing the opening by the cap 13, and FIG. 4 shows an example of opening and closing by the cock 14, respectively. )

  When the eluent 10 of the present invention shown in any of FIGS. 2 to 4 is provided in a liquid chromatograph apparatus, it is airtight with a pipe communicating with the liquid feed pump of the liquid chromatograph apparatus provided in the flexible container 11. What is necessary is just to connect the pipe | tube connected to the said liquid feeding pump to the connectable opening part 12, maintaining airtightness. 5 and 6 show the configuration of a liquid chromatograph apparatus provided with the eluent 10 of the present invention shown in any of FIGS. In addition, when the tube 17 connected to the opening 12 is not provided, the configuration shown in FIG. 5 is used, and when the tube 17 connected to the opening 12 is provided, the configuration shown in FIG. After the eluent 10 is provided in the liquid chromatograph apparatus, the amount of the eluent 15 decreases as the eluent 15 filled in the flexible container is sent by the liquid feed pump 2, but the eluent 10 is kept airtight. Therefore, the flexible container 11 is deformed as the eluent 15 filled in the flexible container decreases.

The eluent of the present invention comprises:
Filling the eluent with a head space in an airtight flexible container provided with at least one opening that can be opened and closed;
Replacing the headspace with an inert gas;
Closing the opening;
Can be manufactured. The eluent of the present invention is only required to be suitable for the nature of the object to be separated or the contaminants and the type of separation material to be used, and includes additives such as acids, bases, salts, and sugars, and organic solvents. It may be a thing.

  In the eluent production method of the present invention, if the eluent to be filled is an eluent preliminarily degassed by the degassing methods (1) to (5) described in the prior art, the degassing state is maintained for a long time. It is possible. On the other hand, as disclosed in the examples, even when the eluent that is not degassed is filled and manufactured, the eluent filled in the container can be degassed and the state can be maintained for a long time. There is no need to degas the eluent before filling.

  In the eluent production method of the present invention, the step of replacing the head space with the inert gas may be performed by simply introducing the inert gas into the head space through the inert gas inlet, or replacing the inert gas with the inert gas inlet. It may be replaced by introducing an inert gas from the tube and bubbling the tube in a state where it is immersed in the eluent filled with the tip of the tube that is more communicated. The replacement by bubbling is preferable because the oxygen gas and nitrogen gas dissolved in the eluent can be efficiently removed in the process of passing the inert gas through the eluent. As disclosed, even when the inert gas is simply introduced into the head space and replaced, the eluent filled in the container can be degassed and maintained in this state for a long time. The present invention can also be applied to a case where replacement by bubbling cannot be performed, such as an eluent containing a highly soluble solvent. When replacing by bubbling, as shown in FIGS. 3 and 4, if a porous body 18 such as porous glass or porous hard resin is provided at the tip of the tube 17 communicating with the inert gas inlet 12b, Since the inert gas that has passed through the body becomes fine bubbles and the contact between the liquid and the inert gas is promoted, it is particularly preferable in that oxygen gas and nitrogen gas dissolved in the eluent can be removed with less inert gas. .

  The eluent of the present invention can be produced by filling a flexible container having airtightness with a headspace, and then replacing the headspace with an inert gas, and eluting before filling. Regardless of whether or not the liquid is deaerated, the deaerated state of the eluent can be maintained for a long time. Further, by providing the liquid chromatograph apparatus with the eluent of the present invention, it is not necessary to provide the liquid chromatograph apparatus with a degassing device such as a vacuum generation source, a vacuum chamber, and an inert gas bubbling apparatus. The size of the apparatus can be reduced.

  Further, the present invention makes it possible to industrially produce a degassed eluent, which has been difficult until now. Therefore, there is no need for the analyst to prepare the degassed eluent before use before analysis. In addition, since an eluent having a degassed and stable composition can be industrially produced, it is possible to provide a stable result with less noise during analysis.

  In the method for producing the eluent of the present invention, the amount of the inert gas used is the amount that replaces the gas in the headspace at the time of production, or the gas dissolved in the eluent and the gas in the headspace are replaced. Since the amount is sufficient, the amount of the inert gas used can be reduced as compared with a conventional degassing method in which an inert gas is constantly flowed and bubbled during analysis. In addition, when replacing the head space with an inert gas, it is not always necessary to introduce the inert gas into the eluent by bubbling and replace the air dissolved in the eluent with the inert gas. It is only necessary to replace with an inert gas. Therefore, the present invention can also be applied to an eluent containing a volatile solvent that is difficult to apply by the conventional degassing method by bubbling of inert gas.

The block diagram of a general liquid chromatograph. The figure which shows the one aspect | mode of the eluent of this invention. The figure which shows another aspect of the eluent of this invention. The figure which shows another aspect of the eluent of this invention. The block diagram of the liquid chromatograph provided with the eluent of this invention. The block diagram of the liquid chromatograph provided with the eluent of this invention. FIG. 3 is a view showing a manufacturing process of the eluent A described in Example 1. FIG. 5 is a diagram showing a manufacturing process of the eluent C described in Example 2.

  Examples will be shown below to describe the present invention in more detail. However, these examples are only examples of the present invention, and the present invention is not limited to the examples.

Example 1
In this example, the eluent 10 shown in FIG. 2 was used. The flexible container 11 used in the eluent 10 is made of a resin film on which aluminum foil is laminated, and has sufficient airtightness. One opening 12 is provided on one side of the flexible container 11, and the mouth can be opened and closed by a cap 13. The capacity of the flexible container 11 used in the eluent 10 is 800 mL.

  The flexible container 11 is filled with 600 mL of tap water as the eluent 15 to be filled in the flexible container, and a PTFE tube 17 (inner diameter 2 mm, outer diameter 3 mm, length 720 mm) for introducing helium is attached to the flexible container 11. After insertion to the bottom, it was bubbled with 2-3 kPa helium for several minutes (FIG. 7). After bubbling, the tube 17 was extracted, and the eluent 10 was manufactured by quickly sealing the head space 16 with helium filled (hereinafter referred to as eluent A). In addition, after filling the flexible container 11 with 600 mL of tap water as the eluent 15 to be filled in the flexible container, the headspace 16 was sealed in a state of being filled with air and manufactured as a control (hereinafter, referred to as “eluent 15”). Eluent B).

  After being left for 3 days, the amount of dissolved oxygen was measured with a dissolved oxygen meter manufactured by Central Science Co., Ltd. in order to estimate the amount of dissolved air. The dissolved oxygen amount of tap water in the eluent A was 1.0 mg / L. On the other hand, the dissolved oxygen amount of tap water in the eluent B was 8.0 mg / L. From this result, it can be seen that the eluent 10 obtained by the production method of the present invention produces a deaerated state and can maintain the state for a long time.

Example 2
In this example, the same eluent 10 shown in FIG.

  A PTFE tube 17 (inner diameter: 2 mm, outer diameter: 3 mm, length: 720 mm), which is filled with 600 mL of tap water as an eluent 15 to be filled in the flexible container, is introduced into the flexible container and helium is introduced. After inserting into the flexible container, the headspace 16 was replaced with helium by blowing 2 to 3 kPa of helium into the headspace 16 for several minutes (FIG. 8). After the replacement with helium, the tube 17 was extracted, and the head space 16 was quickly sealed in a state in which helium was filled to produce the eluent 10 (hereinafter referred to as eluent C). As a control, the eluent B of Example 1 was used.

  After being left for 3 days, the amount of dissolved oxygen was measured with a dissolved oxygen meter manufactured by Central Science Co., Ltd. in order to estimate the amount of dissolved air. The dissolved oxygen amount of tap water in the eluent C was 1.7 mg / L. On the other hand, the dissolved oxygen amount of tap water in the eluent B was 8.0 mg / L. From this result, when producing the eluent 10 of the present invention, the eluent 10 is degassed and degassed as long as the head space 16 is replaced with the inert gas without bubbling the inert gas. It can be seen that it can be maintained for a long time.

  The present invention can be used as an eluent used in analysis. In addition, since the eluent of the present invention can be produced by an easy method and a degassed state can be produced and maintained for a long time, the degassed eluent can be produced industrially. .

1: Eluent 2: Liquid feeding pump 3: Sample introduction device 4: Separation column 5: Detector 10: Eluent of the present invention 11: Flexible container 12: Opening portion 13: Cap 14: Cock 15: Flexible Eluent filled in container 16: Head space 17: Tube 18: Porous body 19: Bubble

Claims (6)

Elution, wherein an airtight flexible container having at least one openable / closable opening is filled with a headspace, and the headspace is filled with an inert gas. liquid. The eluent of claim 1, wherein the inert gas is helium or neon. Filling the eluent with a head space in an airtight flexible container provided with at least one opening that can be opened and closed;
Replacing the headspace with an inert gas;
Closing the opening;
An eluent production method comprising: The manufacturing method according to claim 3, wherein the step of replacing the head space with an inert gas is a step of introducing and replacing the inert gas into the head space. The manufacturing method according to claim 3, wherein the step of replacing the head space with an inert gas is a step of bubbling the inert gas to replace the head space. The manufacturing method according to claim 3, wherein the inert gas is helium or neon.

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