JPH03165258A - Ion chromatograph - Google Patents
Ion chromatographInfo
- Publication number
- JPH03165258A JPH03165258A JP1303141A JP30314189A JPH03165258A JP H03165258 A JPH03165258 A JP H03165258A JP 1303141 A JP1303141 A JP 1303141A JP 30314189 A JP30314189 A JP 30314189A JP H03165258 A JPH03165258 A JP H03165258A
- Authority
- JP
- Japan
- Prior art keywords
- choline
- suppressor
- tmaoh
- deriv
- eluent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229960001231 choline Drugs 0.000 claims abstract description 23
- OEYIOHPDSNJKLS-UHFFFAOYSA-N choline Chemical compound C[N+](C)(C)CCO OEYIOHPDSNJKLS-UHFFFAOYSA-N 0.000 claims abstract description 22
- 230000008929 regeneration Effects 0.000 claims description 20
- 238000011069 regeneration method Methods 0.000 claims description 20
- 239000003480 eluent Substances 0.000 claims description 16
- 150000002500 ions Chemical class 0.000 claims description 14
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 claims description 12
- 239000003456 ion exchange resin Substances 0.000 claims description 12
- 229920003303 ion-exchange polymer Polymers 0.000 claims description 12
- 150000001768 cations Chemical class 0.000 claims description 9
- 238000004458 analytical method Methods 0.000 claims description 6
- 150000003248 quinolines Chemical class 0.000 claims description 6
- 238000000926 separation method Methods 0.000 claims description 6
- 238000001514 detection method Methods 0.000 claims description 3
- WGTYBPLFGIVFAS-UHFFFAOYSA-M tetramethylammonium hydroxide Chemical compound [OH-].C[N+](C)(C)C WGTYBPLFGIVFAS-UHFFFAOYSA-M 0.000 abstract description 21
- 239000007788 liquid Substances 0.000 abstract description 17
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 abstract description 14
- 230000001172 regenerating effect Effects 0.000 abstract description 13
- 230000000694 effects Effects 0.000 abstract description 7
- 239000012528 membrane Substances 0.000 abstract description 7
- 239000001763 2-hydroxyethyl(trimethyl)azanium Substances 0.000 abstract description 2
- JJCWKVUUIFLXNZ-UHFFFAOYSA-M 2-hydroxyethyl(trimethyl)azanium;bromide Chemical compound [Br-].C[N+](C)(C)CCO JJCWKVUUIFLXNZ-UHFFFAOYSA-M 0.000 abstract description 2
- 235000019743 Choline chloride Nutrition 0.000 abstract description 2
- 229960003178 choline chloride Drugs 0.000 abstract description 2
- SGMZJAMFUVOLNK-UHFFFAOYSA-M choline chloride Chemical compound [Cl-].C[N+](C)(C)CCO SGMZJAMFUVOLNK-UHFFFAOYSA-M 0.000 abstract description 2
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 abstract 2
- KIZQNNOULOCVDM-UHFFFAOYSA-M 2-hydroxyethyl(trimethyl)azanium;hydroxide Chemical compound [OH-].C[N+](C)(C)CCO KIZQNNOULOCVDM-UHFFFAOYSA-M 0.000 abstract 1
- 239000000463 material Substances 0.000 abstract 1
- 238000004255 ion exchange chromatography Methods 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 3
- 229940112042 peripherally acting choline derivative muscle relaxants Drugs 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000005342 ion exchange Methods 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 150000001450 anions Chemical class 0.000 description 1
- 229960004874 choline bitartrate Drugs 0.000 description 1
- QWJSAWXRUVVRLH-UHFFFAOYSA-M choline bitartrate Chemical compound C[N+](C)(C)CCO.OC(=O)C(O)C(O)C([O-])=O QWJSAWXRUVVRLH-UHFFFAOYSA-M 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000012492 regenerant Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Treatment Of Liquids With Adsorbents In General (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明は、陽イオンのイオンクロマトグラフィに用いら
れるサプレッサの再生液を改良したイオンクロマトグラ
フに関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an ion chromatograph with an improved suppressor regeneration solution used in ion chromatography of cations.
（従来の技術）
イオンクロマトグラフは、高感度な陰・陽イオン分析装
置として、広く用いられている。(Prior Art) Ion chromatographs are widely used as highly sensitive anion/cation analyzers.
このイオンクロマトグラフにおいては、サンプルインジ
ェクタにおいてサンプルを溶離液により溶離し、この溶
離したサンプルを分離カラムにおいてイオン交換樹脂に
より分離している。In this ion chromatograph, a sample is eluted with an eluent in a sample injector, and the eluted sample is separated in a separation column using an ion exchange resin.
そして、この種のイオンクロマトグラフにおいては、前
記分離カラムで分離されたイオンの中で、前記溶離液の
イオン等、分析しようとするイオンの逆の電荷を持つイ
オンを、サプレッサ（サプレッサカラム）で除去し、バ
ックグランドの電気伝導度を下げることにより、高感度
の電気伝導度検出器を用いての高感度な分析を可能とし
ている。In this type of ion chromatograph, a suppressor (suppressor column) is used to suppress ions that have an opposite charge to the ions to be analyzed, such as ions in the eluent, from among the ions separated by the separation column. By removing it and lowering the background electrical conductivity, highly sensitive analysis using a highly sensitive electrical conductivity detector is possible.
前記サプレッサカラムとしては、従来、高容量のイオン
交換カラムが使用されていたが、近年、ファイバサプレ
ッサ、さらにマイクロメンブレンサプレッサ等が開発さ
れ、前記イオンの除去と同時にイオン交換自体の再生が
可能となり、分析が迅速化されている。Conventionally, high-capacity ion exchange columns have been used as the suppressor column, but in recent years, fiber suppressors, micromembrane suppressors, etc. have been developed, making it possible to simultaneously remove the ions and regenerate the ion exchange itself. Analysis is faster.
とれらのサプレッサは、第３図に示すように、矢印Ａ方
向に沿って流動する溶離液１の所要距離をイオン交換樹
脂膜２で包囲するとともに、この膜２の外側に再生液３
を例えば矢印Ｂ＋から矢印Ｂ２へと流す構成をとるもの
で、再生液３としては、一般に、水酸化ナトリウム（Ｎ
ａ ＯＨ）や水酸化テトラメチルアンモニウム（ＴＭ
ＡＯＨ）等が多用されている。As shown in FIG. 3, these suppressors surround the required distance of the eluent 1 flowing in the direction of arrow A with an ion exchange resin membrane 2, and a regenerating liquid 3 is placed on the outside of this membrane 2.
For example, the regenerating liquid 3 is made of sodium hydroxide (N
a OH) and tetramethylammonium hydroxide (TM
AOH) etc. are often used.
前記サプレッサにおいて、例えば陽イオンＬｉ、Ｎａ”
、ＮＨ４” 、に＋の分離、検出を目的とし、再生液
３として前記ＮａＯＨ、イオン交換樹脂膜２としてアミ
ン系樹脂（ＲＮ＋０Ｆ−１＞、溶離液１として塩酸（Ｍ
ＣＩ ）をそれぞれ用いると、溶離液１を除去する除去
反応、およびイオン交換樹脂ｗＡ２を再生する再生反応
は、以下のように行われる。In the suppressor, for example, cations Li, Na''
For the purpose of separating and detecting +,
CI ), the removal reaction to remove eluent 1 and the regeneration reaction to regenerate ion exchange resin wA2 are performed as follows.
すなわち、除去反応は、下式に示すように、溶離液１で
あるＨＣＩと、イオン交換樹脂膜２とが反応し、電気伝
導度の低いＨ２Ｏに変換されるものである。That is, in the removal reaction, as shown in the formula below, HCI, which is the eluent 1, reacts with the ion exchange resin membrane 2, and is converted into H2O, which has low electrical conductivity.
ＨＣ！ ＋ＲＮ＋ ＯＨ→ＲＮ” ＣＩ−＋８．０ま
た、再生反応は、下式に示すように、前記除去反応で活
性が失われたイオン交換樹脂ＭＲＮ”ＣＩ−が、イオン
交換樹脂ＪＩＩｉ２の外側に流される再生液Ｎ ａ Ｏ
Ｈと反応し、再生されるものである。HC! +RN+ OH→RN” CI-+8.0 In addition, in the regeneration reaction, as shown in the formula below, the ion exchange resin MRN"CI- whose activity has been lost in the removal reaction is flowed to the outside of the ion exchange resin JIIi2. Regeneration liquid N a O
It reacts with H and is regenerated.
ＲＮ＋Ｃｌ−＋ＮａＯＨ−＋ＲＮ＋ＯＨ＋Ｎａにのよう
に、除去反応と再生反応とが同時に行われるなかで、溶
離液１濃度が高い等で除去反応が再生反応より進むと、
イオン交換樹脂膜２の活性が失われ、溶離液１の残留が
起こる。すなわち、バックグランドの上昇を生じる。As in RN+Cl-+NaOH-+RN+OH+Na, when the removal reaction and regeneration reaction are performed simultaneously, if the eluent 1 concentration is high and the removal reaction proceeds faster than the regeneration reaction,
The activity of the ion exchange resin membrane 2 is lost, and the eluent 1 remains. In other words, the background increases.
この溶離液１の残留を防ぐためには、再生を早める必要
があるが、再生を早めようとして再生液３の圧力を高め
る際、再生液としてＮａＯＨあるいは前記ＴＭＡＯＨの
ように分子半径が小さい分子の溶液を用いていると、Ｎ
ａ＋または（ＣＨ，＞４Ｎ＋がイオン交換樹脂Ｍ２を通
過して分析系に混入し、この再生液側圧力増加でもバッ
クグランドを上昇させてしまう。In order to prevent this eluent 1 from remaining, it is necessary to speed up the regeneration, but when increasing the pressure of the regeneration fluid 3 in order to speed up the regeneration, the regeneration fluid is a solution of molecules with a small molecular radius such as NaOH or TMAOH. When using N
a+ or (CH, >4N+) passes through the ion exchange resin M2 and mixes into the analysis system, and this increase in pressure on the regeneration liquid side also increases the background.
（発明が解決しようとする課題）
このように、従来においては、再生液３の分子半径が適
切でないことにより、バ・ツクグランドが高くなるとい
う問題があった。(Problems to be Solved by the Invention) As described above, in the past, there was a problem in that the background level became high due to the inappropriate molecular radius of the regenerating liquid 3.
本発明はこのような従来技術の問題を考慮してなされた
ものであり、バ・ツクグランドが低ν）状態で分析を行
えるイオンクロマトグラフを提供することを目的とする
。The present invention has been made in consideration of the problems of the prior art, and it is an object of the present invention to provide an ion chromatograph that can perform analysis in a state where the background ground is low (v).
［発明の構成］
（課題を解決するための手段および作用）本発明者らは
、上記目的を達成するために鋭意研究を重ねる中で、コ
リンないしコリン誘導体を、陽イオンのイオンクロマト
グラフィに用６ｔられるサプレッサカラムの再生液に用
１１れば、著しい効果が得られることを見出だして本発
明を完成するに至った。[Structure of the Invention] (Means and Effects for Solving the Problems) In order to achieve the above object, the present inventors have conducted intensive research and discovered that choline or choline derivatives are used for ion chromatography of cations. The present inventors have discovered that a remarkable effect can be obtained by using the present invention as a regenerating liquid for a suppressor column, and have completed the present invention.
すなわち、本発明は、サンプルインジェクタで溶離液に
より溶離されたサンプルを、分離カラムにおいてイオン
交換樹脂で分離し、サブレ・ノサ（こおいて前記溶離液
の除去を行った後、前記サプレッサより送られてくる陽
イオンを検出分析するイオンクロマトグラフにおいて、
前記サブレ・ノサの再生液に、コリン（２−しドロキシ
エチルトリメチルアンモニウム水酸化物）ないしコリン
誘導体を含有することを特徴としている。That is, in the present invention, a sample eluted with an eluent by a sample injector is separated using an ion exchange resin in a separation column, and after the eluent is removed there, the sample is sent from the suppressor. In ion chromatography, which detects and analyzes cations that
It is characterized in that the Sable Nosa regeneration liquid contains choline (2-droxyethyltrimethylammonium hydroxide) or a choline derivative.
本発明にがかるコリン誘導体としては、塩化コリン、重
酒石酸コリン、臭化コリン等を挙げることができる。Examples of the choline derivatives according to the present invention include choline chloride, choline bitartrate, choline bromide, and the like.
また、これらコリンないしコリン誘導体の再生液におけ
る濃度は、５〜５００ｍＭが望ましく、２０〜１００ｍ
Ｍがより望ましい、前記濃度を５〜５００ｍＭが望まし
いとしたのは、５ｍＭ未満の濃度では、空気中のＣＯ３
とコリンとの反応で溶離時間が変化し易くなるためであ
り、５００ｍＭを越えると、分析系へのＯＨ−混入によ
り、ノくツクグランドが変化しやすいためである。The concentration of these choline or choline derivatives in the regeneration solution is preferably 5 to 500mM, and 20 to 100mM.
The reason why M is more desirable and the concentration is 5 to 500mM is because at a concentration of less than 5mM, CO3 in the air
This is because the elution time tends to change due to the reaction between choline and choline, and when it exceeds 500 mM, the reaction ground tends to change due to OH- contamination in the analysis system.
また、本発明にかかるイオンクロマトグラフの装置構成
としては、第２図に示すように、サンプル１１と溶離液
１とが注入されるサンプフレインジェクタ１２と、溶離
液１で溶離されたサンプル１１をイオン交換樹脂により
分離する分離カラム１３と、溶離液１の除去等を行うサ
ブレ・ノサ１４と、サプレッサ１４から送られてくるイ
オンを検出分析し、検出器（電気伝導度セル＞１５ａ、
電気伝導度計１５ｂ、記録計１５ｃ等備えた検出部１５
等が挙げられる。As shown in FIG. 2, the device configuration of the ion chromatograph according to the present invention includes a sump injector 12 into which the sample 11 and the eluent 1 are injected, and a sample 11 eluted with the eluent 1. A separation column 13 that separates using an ion exchange resin, a sublet nosa 14 that removes the eluent 1, etc. detect and analyze ions sent from the suppressor 14, and a detector (electrical conductivity cell>15a,
Detection unit 15 equipped with an electrical conductivity meter 15b, a recorder 15c, etc.
etc.
コリンは、現在使用されているアルカリ性物質のＮａＯ
Ｈ，ＫＯＨ，ＴＭＡＯ）（と比較し、十分分子半径が大
きく、サプレッサカラムの膜を通過し難いため、再生液
圧力を上げてもバックグランドが上昇し難い、また、コ
リンは、ＴＭＡＯＨと比較しアルカリ性が強いため、Ｔ
ＭＡＯＩ−１より低濃度・低圧力で同じ効果を得ること
ができる。さらに、コリンは、ＴＭＡＯＨより安定度が
良好で価格も低いという利点がある。Choline is the alkaline substance currently used, NaO.
Choline has a sufficiently large molecular radius and is difficult to pass through the membrane of the suppressor column, so even if the regeneration liquid pressure is increased, the background does not easily increase. Due to its strong alkalinity, T
The same effect can be obtained at a lower concentration and pressure than MAOI-1. Furthermore, choline has the advantage of better stability and lower cost than TMAOH.
（実施例）
実施例１
上田の第２図に示したような装置構成を有するイオンク
ロマトグラフで、第３図に示したような構成を有する陽
イオン用マイクロメンブレンサプレッサを用いるととも
に、溶離液として塩酸２５ｍＭ（流速１ｍｌ／ｍ）、再
生液として５０ｍＭ−コリンをそれぞれ用い、陽イオン
Ｌｉ＋、Ｎａ＋ＮＨ４” 、に＋のイオンクロマトグラ
フィを行うことにより、第１図（ａ）に示すようなりロ
マトグラムを得た。(Example) Example 1 An ion chromatograph having the device configuration as shown in Ueda's Figure 2 was used, and a cation micromembrane suppressor having the configuration as shown in Figure 3 was used. By using 25mM hydrochloric acid (flow rate 1ml/m) and 50mM-choline as the regenerating solution, ion chromatography of cations Li+, Na+NH4'', and + was performed to obtain a chromatogram as shown in Figure 1(a). .
比較例１〜２
再生液に、比較例１として４０ｍＭ−ＴＭＡＯＨ１比較
例２として１００ｍＭ−ＮａＯＨを用いた他は、実ｊｉ
！Ｐｓｌと同様にしてイオンクロマトグラフィを行い、
第１図（ｂ）、（ｃ）に示すようなりロマトグラムを得
た。Comparative Examples 1 to 2 The actual examples were the same, except that 40mM-TMAOH was used as the regenerating solution in Comparative Example 1, and 100mM-NaOH was used as Comparative Example 2.
! Perform ion chromatography in the same manner as Psl,
A chromatogram as shown in FIGS. 1(b) and 1(c) was obtained.
第１図（ａ）〜（Ｃ）から明らかなように、コリンを再
生液として用い得られた値は、ピーク値については、Ｎ
ａＯＨを再生液として用いて得られた値と同等であるが
、ＴＭＡＯＨおよびＮａＯＨを再生液として用いて得ら
れた値と比較し、バックグランドの値が大幅に改善され
ており、感度良く測定を行えることがわかった。As is clear from FIGS. 1(a) to (C), the values obtained using choline as the regenerant are as follows:
Although the values are equivalent to those obtained using aOH as the regenerating liquid, the background values are significantly improved compared to the values obtained using TMAOH and NaOH as the regenerating liquid, and the measurement can be performed with good sensitivity. I found out that it can be done.
［発明の効果］
以上の説明から明らかなように、陽イオンのイオンクロ
マトグラフィに用いられるサプレッサカラムの再生液に
、コリンないしコリン誘導体を含有することにより、Ｎ
ａＯＨ再生液およびＴＭＡＯＨ再生液で得られた値と比
較し、バックグランドの値を大幅に改善しており、その
工業的価値は極めて大きい。[Effect of the invention] As is clear from the above explanation, by containing choline or a choline derivative in the regenerating solution of the suppressor column used for ion chromatography of cations, N
Compared to the values obtained with the aOH regenerated liquid and the TMAOH regenerated liquid, the background value is significantly improved, and its industrial value is extremely large.
第１図（ａ＞、（ｂ）、（ｃ）はそれぞれ本発明にかか
るコリン再生液、ＴＭＡＯＨ再生液、Ｎａｏｌ−１再生
液を用いて得られたクロマトグラム、第２図は本発明に
かがるイオンクロマトグラフの概略装置構成図、第３図
はマイクロメンブレンサプレッサ等のサプレッサカラム
の要部構成説明図である。
ｌ・・・溶離液 ２・・・イオン交換樹脂膜３・
・・再生液 １２・・・サンプルインジェクタ１３
・・・分離カラム １４・・・サプレッサ１５・・・検
出部Figure 1 (a>, (b), and (c) are chromatograms obtained using the choline regeneration solution, TMAOH regeneration solution, and Naol-1 regeneration solution according to the present invention, respectively, and Figure 2 is the chromatogram obtained using the choline regeneration solution according to the present invention, respectively. Figure 3 is an explanatory diagram of the main part configuration of a suppressor column such as a micromembrane suppressor.l... Eluent 2... Ion exchange resin membrane 3.
... Regeneration liquid 12 ... Sample injector 13
... Separation column 14 ... Suppressor 15 ... Detection section
Claims (1)
ルを、分離カラムにおいてイオン交換樹脂で分離し、サ
プレッサにおいて前記溶離液の除去を行つた後、前記サ
プレッサより送られてくる陽イオンを検出分析するイオ
ンクロマトグラフにおいて、 前記サプレッサの再生液に、コリンないしコリン誘導体
を含有することを特徴とするイオンクロマトグラフ。[Scope of Claims] A sample eluted with an eluent by a sample injector is separated with an ion exchange resin in a separation column, and the eluent is removed in a suppressor, and then the cations sent from the suppressor are removed. An ion chromatograph for detection and analysis, characterized in that the suppressor regeneration solution contains choline or a choline derivative.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1303141A JPH03165258A (en) | 1989-11-24 | 1989-11-24 | Ion chromatograph |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1303141A JPH03165258A (en) | 1989-11-24 | 1989-11-24 | Ion chromatograph |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03165258A true JPH03165258A (en) | 1991-07-17 |
Family
ID=17917375
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1303141A Pending JPH03165258A (en) | 1989-11-24 | 1989-11-24 | Ion chromatograph |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03165258A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107367561A (en) * | 2017-07-26 | 2017-11-21 | 内蒙古蒙牛乳业（集团）股份有限公司 | The method for detecting Choline Chloride in dairy products |
-
1989
- 1989-11-24 JP JP1303141A patent/JPH03165258A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107367561A (en) * | 2017-07-26 | 2017-11-21 | 内蒙古蒙牛乳业（集团）股份有限公司 | The method for detecting Choline Chloride in dairy products |
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