JP2013088412A - Flow cell for liquid chromatograph - Google Patents

Flow cell for liquid chromatograph Download PDF

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Publication number
JP2013088412A
JP2013088412A JP2011232443A JP2011232443A JP2013088412A JP 2013088412 A JP2013088412 A JP 2013088412A JP 2011232443 A JP2011232443 A JP 2011232443A JP 2011232443 A JP2011232443 A JP 2011232443A JP 2013088412 A JP2013088412 A JP 2013088412A
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refractive index
flow cell
liquid
porous film
light
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Hideyuki Akiyama
秀之 秋山
Shigeru Matsui
繁 松井
Yusuke Goto
佑介 後藤
Masao Kamahori
政男 釜堀
Hiroshi Sasaki
佐々木  洋
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Hitachi High Tech Corp
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Hitachi High Technologies Corp
Hitachi High Tech Corp
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Abstract

PROBLEM TO BE SOLVED: To provide a long light path flow cell capable of securing a transmission light quantity needed for increasing sensitivity of a detector for liquid chromatograph.SOLUTION: An inner wall surface of a flow cell flow path is covered with a porous film having many fine air gaps filled with air and having a refractive index lower than that of water. One of methods of achieving a low refractive index material is the porous film. It is a film having many fine air gaps filled with air inside, and the refractive index has a value in the middle of the refractive index of a film material and the refractive index of air. Thus, by a selection of the film material and a ratio of the air gaps of the whole porous film, the refractive index lower than that of water is achieved.

Description

本発明は、液体クロマトグラフ用フローセルに関し、特に測定試料の高感度検出に好適な長光路長をもつフローセルに関する。   The present invention relates to a flow cell for liquid chromatography, and more particularly to a flow cell having a long optical path length suitable for highly sensitive detection of a measurement sample.

液体クロマトグラフは、移動相を送液する送液部、測定試料を流路に注入する試料注入部、測定試料を各成分に分離する分離部および分離された成分ごとに検出する検出部より構成される。このうち検出部は主に光学的検出方法が採用されており、中でも試料の吸光度を測定する方法が最も一般的である。液体クロマトグラフ用吸光度検出器は試料の吸光度を測定するためのフローセルが備えられており、これは通常円筒形の流路を有し、この流路の一端面より長手方向に光を入射し、他端面より出射された光を光検出器にて測定する構成となっている。入射光量と出射光量の比の対数を計算することにより、フローセル流路内に収容された試料成分の吸光度を求めることができる。試料成分の吸光度は成分濃度に比例するため、吸光度のクロマトグラムのピーク面積が当該成分の試料中に含まれる物質量に相当する。   The liquid chromatograph is composed of a liquid feeding part for feeding a mobile phase, a sample injection part for injecting a measurement sample into a flow path, a separation part for separating the measurement sample into each component, and a detection part for detecting each separated component. Is done. Of these, an optical detection method is mainly used for the detection unit, and among them, the method of measuring the absorbance of the sample is the most common. The absorbance detector for a liquid chromatograph is provided with a flow cell for measuring the absorbance of a sample, which usually has a cylindrical flow path, and receives light in the longitudinal direction from one end face of the flow path. The light emitted from the other end surface is measured by a photodetector. By calculating the logarithm of the ratio of the incident light quantity and the outgoing light quantity, the absorbance of the sample component accommodated in the flow cell channel can be obtained. Since the absorbance of the sample component is proportional to the component concentration, the peak area of the absorbance chromatogram corresponds to the amount of substance contained in the sample of the component.

米国特許3770350号U.S. Pat. No. 3,770,350 特開平5−196565号公報JP-A-5-196565

液体クロマトグラフでは、その高感度化の要求より、フローセルの長光路化が志向されている。これは検出に吸光度検出器を用いた場合、得られる試料のピーク高さSが試料を透過する光の光路長に比例するため、フローセルの光路長Lを延長することにより検出器の検出感度を向上させることが可能であるからである。   In liquid chromatographs, the flow path has a longer optical path due to the demand for higher sensitivity. This is because when the absorbance detector is used for detection, the peak height S of the obtained sample is proportional to the optical path length of the light passing through the sample. Therefore, the detection sensitivity of the detector is increased by extending the optical path length L of the flow cell. This is because it can be improved.

しかしながら、光路長を単純に延長した場合、これに比例してフローセルの光路容量も増加し、これによりクロマトピークのブロードニングが起こり、試料の各成分ピークの分離性能が悪化する。このため分離性能を維持したまま光路長を延長するには光路の断面積Aを光路長Lに反比例して小さくしなければならない。結果、フローセルの流路の形状は細く長くなり、これに光を透過させた場合の透過光量はおおむねフローセル流路の入射口中心から出射口を見込む立体角Ωに比例する。フローセル流路の立体角Ωは
Ω≒A/L2 …(1)
で表され、さらに上述の条件により
A∝1/L …(2)
が成り立つ。ベースラインノイズNは 透過光量Eに対し
N∝1/√E …(3)
が成り立つことが知られており、この透過光量Eについては上述のとおり
E∝Ω …(4)
が成り立つ。クロマトピーク高さSについては上述のとおり
S∝L …(5)
がなりたつため、(1)から(5)の関係式より、クロマトピークのS/N比について
S/N∝L×√E∝L×√Ω∝L×√1/L3=1/√L …(6)
となり、単純に光路長を延長しただけではクロマトピークのS/N比が却って悪化する結果となり、これがネックとなって吸光度検出器のフローセルの長光路化は実現が遅れていた。
However, when the optical path length is simply extended, the optical path capacity of the flow cell also increases in proportion to this, thereby causing broadening of chromatographic peaks and degrading the separation performance of each component peak of the sample. Therefore, in order to extend the optical path length while maintaining the separation performance, the cross-sectional area A of the optical path must be reduced in inverse proportion to the optical path length L. As a result, the shape of the flow channel of the flow cell becomes thin and long, and the amount of transmitted light when light is transmitted through the flow cell is roughly proportional to the solid angle Ω at which the exit is viewed from the center of the entrance of the flow cell. The solid angle Ω of the flow cell channel is Ω ≒ A / L 2 (1)
Furthermore, according to the above-mentioned conditions, A∝1 / L (2)
Holds. Baseline noise N is N∝1 / √E with respect to transmitted light E (3)
As described above, the transmitted light amount E is E∝Ω (4)
Holds. As described above, the chromatographic peak height S is S∝L (5)
Therefore, from the relational expressions (1) to (5), the S / N ratio of the chromatopeak is S / N∝L × √E∝L × √Ω∝L × √1 / L 3 = 1 / √L (6)
Thus, simply extending the optical path length resulted in a worsening of the S / N ratio of the chromatopeak, which became a bottleneck, and the realization of the long optical path of the absorbance detector was delayed.

この問題の解決方法としてフローセル内壁を水よりも屈折率が低い材料にて被覆し、入射光をフローセル内壁面において全反射させ、フローセル流路自体を光導波路とすることにより、フローセル流路以上の広い立体角の入射光束を損失なく透過させることが可能となる。
近年になって特許文献2に見られるようにフローセル内壁にアモルファスフルオロポリマーを使用し、これによってフローセルの長光路化による高感度化に目途が立つようになった。アモルファスフルオロポリマーは屈折率が1.29と水やメタノールといった通常の液体クロマトグラフィーの移動相に使用する溶媒よりも低い値を持つことが特徴である。
しかしながら、この従来技術は下記の示す問題点を有する。
As a solution to this problem, the inner wall of the flow cell is coated with a material having a lower refractive index than water, the incident light is totally reflected on the inner wall of the flow cell, and the flow cell channel itself is used as an optical waveguide. An incident light beam having a wide solid angle can be transmitted without loss.
In recent years, as shown in Patent Document 2, an amorphous fluoropolymer is used on the inner wall of the flow cell, and as a result, high sensitivity due to the long optical path of the flow cell has become prominent. Amorphous fluoropolymers are characterized by a refractive index of 1.29, which is lower than the solvent used in the mobile phase of normal liquid chromatography such as water and methanol.
However, this prior art has the following problems.

アモルファスフルオロポリマーをフローセル内壁材料に用いる方法では内壁面の屈折率が材料固有の値にて規定されるため、現状以上の低屈折率化への余地がない。   In the method of using an amorphous fluoropolymer for the inner wall material of the flow cell, the refractive index of the inner wall surface is defined by a value specific to the material, so there is no room for lowering the refractive index than the current level.

よって、フローセル流路に取り込むことができる光束の立体角も現状以上に拡大することが不可能である。   Therefore, the solid angle of the light beam that can be taken into the flow cell channel cannot be increased beyond the current level.

移動相に水を用いた場合の入射光束の取込立体角は0.192srにとどまり、この値は従来の標準的なフローセル(例えば内径1.3mm、光路長10mm)にて取込可能な立体角0.133srと比較して拡大されているものの、フローセルの長光路化に伴う入射口径の縮小によって入射口に結像する光源像を従来よりも小さくする必要があるため、縮小系の照明光学系を使用せざるをえず、入射光束の立体角がより拡大することからフローセル側の取込可能な立体角も更に拡大することが望ましい。   When water is used as the mobile phase, the incident solid angle of the incident light beam is limited to 0.192 sr, and this value is a solid that can be captured by a conventional standard flow cell (for example, an inner diameter of 1.3 mm and an optical path length of 10 mm). Although it is enlarged as compared with the angle of 0.133 sr, it is necessary to make the light source image formed at the entrance aperture smaller by reducing the entrance aperture due to the longer optical path of the flow cell. A system must be used, and the solid angle of the incident light beam is further expanded, so that it is desirable to further increase the solid angle that can be captured on the flow cell side.

また、高速液体クロマトグラフィーでは移動相の送液にプランジャーポンプを使用するのが一般的であり、プランジャーの往復動作に同期した圧力リップルの発生が避けられない。この圧力リップルによって移動相の屈折率変動が生じ、これがフローセル内壁での全反射の臨界角が増減することとなり、最終的にはフローセルの透過光量変動によるベースラインノイズの増加につながる。   In high-performance liquid chromatography, a plunger pump is generally used to send the mobile phase, and the generation of pressure ripples that are synchronized with the reciprocating movement of the plunger is inevitable. This pressure ripple causes a change in the refractive index of the mobile phase, which increases or decreases the critical angle of total reflection on the inner wall of the flow cell, and ultimately leads to an increase in baseline noise due to fluctuations in the amount of light transmitted through the flow cell.

この透過光量変動は移動相の屈折率とフローセル内壁の屈折率との差が小さいほど顕著となる。例えば移動相として水(屈折率1.33)、フローセル内壁にアモルファスフルオロポリマー(屈折率1.29)を使用した場合、水の屈折率が±0.1%変動した場合、フローセルに取込可能な光束の立体角の変動率は±3.3%となるが、フローセル内壁の屈折率を仮に1.25とした場合の同変動率は±1.6%と半減する。   This transmitted light amount variation becomes more prominent as the difference between the refractive index of the mobile phase and the refractive index of the inner wall of the flow cell is smaller. For example, when water (refractive index: 1.33) is used as the mobile phase and amorphous fluoropolymer (refractive index: 1.29) is used on the inner wall of the flow cell, it can be taken into the flow cell if the refractive index of water fluctuates by ± 0.1%. The variation rate of the solid angle of a simple light beam is ± 3.3%, but when the refractive index of the inner wall of the flow cell is 1.25, the variation rate is halved to ± 1.6%.

よって、移動相送液時の圧力リップルによるベースラインノイズを改善するためにはフローセル内壁の屈折率を可能な限り低く抑えることが効果的である。   Therefore, in order to improve baseline noise due to pressure ripple during mobile phase liquid feeding, it is effective to keep the refractive index of the inner wall of the flow cell as low as possible.

本発明は、液体クロマトグラフ用検出器の高感度化を実現するために必要な透過光量を確保できる長光路フローセルを提供することを目的とする。   An object of this invention is to provide the long optical path flow cell which can ensure the transmitted light amount required in order to implement | achieve the high sensitivity of the detector for liquid chromatographs.

本発明は、フローセル流路の内壁面を、空気にて充満された微細な空隙を多数有し、水よりも低い屈折率をもつ多孔質膜にて被覆する。   In the present invention, the inner wall surface of the flow cell channel is covered with a porous film having many fine voids filled with air and having a refractive index lower than that of water.

低屈折率材料の実現方法の1つに多孔質膜が挙げられる。これは空気で充満された微細な空隙を内部に多数もつ膜であり、屈折率が膜材料の屈折率と空気の屈折率との中間の値を持つことが特徴である。このため、膜材料の選択と全体に占める空隙の割合によって、水よりも低い屈折率を実現することが可能である。   One method for realizing a low refractive index material is a porous film. This is a film having a number of minute voids filled with air inside, and is characterized in that the refractive index has an intermediate value between the refractive index of the film material and the refractive index of air. For this reason, it is possible to realize a refractive index lower than that of water depending on the selection of the film material and the ratio of voids to the whole.

上記多孔質膜は内部に空気を包含することにより低屈折率を実現するため、接液によって空隙が全て移動相に置換されると膜の屈折率が移動相より高くなり、全反射が起こらなくなってしまう。また、移動相への置換が経時的に進行すると膜の屈折率もこれに合わせて増加し、経時的なフローセルの取込立体角減少によるベースラインドリフトが発生してしまう。   Since the porous film realizes a low refractive index by including air inside, the refractive index of the film becomes higher than that of the mobile phase when the voids are completely replaced by the mobile phase, and total reflection does not occur. End up. Further, when the replacement with the mobile phase proceeds with time, the refractive index of the film also increases accordingly, and baseline drift occurs due to the decrease in the solid angle of the flow cell taken with time.

これらを防止するために多孔質膜の表面部には内部空隙への液体の浸入を防止する保護層を設ける必要がある。この際に保護層の厚さを入射光の波長よりも薄くしておけば保護層自体が持つ屈折率によって膜と移動相界面での全反射が阻害されないようにすることができる。   In order to prevent these, it is necessary to provide a protective layer for preventing liquid from entering the internal voids on the surface of the porous membrane. At this time, if the thickness of the protective layer is made thinner than the wavelength of the incident light, the total reflection at the interface between the film and the mobile phase can be prevented from being hindered by the refractive index of the protective layer itself.

前述のとおりアモルファスフルオロポリマーは現状以上の低屈折率化の余地が残されていないのに対し、この多孔質膜は低屈折率膜材料の採用と高空隙率化により更に低屈折率化することが可能である。   As described above, there is no room for lowering the refractive index of amorphous fluoropolymer than it is currently, whereas this porous film has a lower refractive index by adopting a low refractive index film material and increasing the porosity. Is possible.

また、材料選択と空隙率の調整によりフローセル内壁の屈折率を制御することも可能である。   It is also possible to control the refractive index of the inner wall of the flow cell by selecting the material and adjusting the porosity.

従来技術ではフローセル内壁の屈折率が材料の固有値によって1点に固定されていたのに対し、本発明では実現可能な屈折率の下限を下げることができ、かつ下限以上の範囲において任意の値に設定することができるため、下記の効果が期待できる。
(1)フローセルに取込可能な立体角を従来以上に拡大することができ、光検出系に到達する光量の増加によりベースラインノイズを低減することができる。
(2)取込立体角を拡大することにより照明光学系の倍率を縮小することができ、フローセルの長光路化に伴う入射口径の縮小に対応することができる。
(3)移動相とフローセル内壁の屈折率差を拡大することにより、送液系による移動相の屈折率変動に起因するベースライン変動を低減することができる。
(4)光学系全体の設計において、照明光学系または取込光学系の光学設計に対しフローセル内壁の屈折率を調整することにより、これらに最適化することができる。
In the prior art, the refractive index of the inner wall of the flow cell is fixed to one point by the eigenvalue of the material, but in the present invention, the lower limit of the refractive index that can be realized can be lowered and can be set to an arbitrary value within the range above the lower limit. Since it can be set, the following effects can be expected.
(1) The solid angle that can be taken into the flow cell can be expanded more than before, and the baseline noise can be reduced by increasing the amount of light reaching the light detection system.
(2) The magnification of the illumination optical system can be reduced by enlarging the capture solid angle, and it is possible to cope with the reduction of the incident aperture due to the longer optical path of the flow cell.
(3) By enlarging the refractive index difference between the mobile phase and the inner wall of the flow cell, it is possible to reduce the baseline fluctuation due to the refractive index fluctuation of the mobile phase due to the liquid feeding system.
(4) The overall design of the optical system can be optimized by adjusting the refractive index of the inner wall of the flow cell with respect to the optical design of the illumination optical system or the capture optical system.

液体クロマトグラフの分析原理の説明図。Explanatory drawing of the analysis principle of a liquid chromatography. 液体クロマトグラフ用ダイオードアレイ検出器の吸光度測定原理の説明図。Explanatory drawing of the light absorbency measurement principle of the diode array detector for liquid chromatographs. 本発明の実施例である液体クロマトグラフ用フローセルの構成図。The block diagram of the flow cell for liquid chromatographs which is an Example of this invention.

以下、本発明の実施例の詳細を述べる。   Details of the embodiments of the present invention will be described below.

〔実施例〕
本発明の実施形態の例として、液体クロマトグラフ用ダイオードアレイ検出器を挙げる。液体クロマトグラフの分析原理を図1の流路図を用いて示す。移動相2は送液ポンプ1により分離カラム5に送られる。分離カラム5はカラム恒温装置4により試料の分離に最適な温度に恒温される。分離カラム5の直前にあるオートサンプラ3には複数の試料がセットされ、一定時間ごとに自動的に分離カラム5に導入される。分離カラムにおいてそれぞれの成分に分離展開され時間差を伴い溶出される。その後、順次にダイオードアレイ検出器6に送られ、成分ごとの吸光度を測定し、PCデータ処理部7にとり入れられ、計算処理されてレポート出力される。
〔Example〕
As an example of an embodiment of the present invention, a diode array detector for a liquid chromatograph is given. The analysis principle of the liquid chromatograph is shown using the flow chart of FIG. The mobile phase 2 is sent to the separation column 5 by the liquid feed pump 1. The separation column 5 is kept at a temperature optimum for the separation of the sample by the column thermostat 4. A plurality of samples are set in the autosampler 3 immediately before the separation column 5 and are automatically introduced into the separation column 5 at regular intervals. Each component is separated and developed in the separation column and eluted with a time difference. Thereafter, the light is sequentially sent to the diode array detector 6 and the absorbance of each component is measured. The absorbance is taken into the PC data processing unit 7, calculated, and output as a report.

液体クロマトグラフ用ダイオードアレイ検出器の吸光度測定原理を図2の構成図を用いて示す。光源11から放射された光源光を集光ミラー12にて集光してフローセル13に導入・透過させる。フローセル透過光を集光レンズ14にてスリット15に導入し、回折格子16にて各波長に分散された光をフォトダイオードアレイ検出器17にて検知し、各時点における透過光量スペクトルを得、これをPCデータ処理部18に格納する。試料成分導入前の透過光量スペクトルを基準として試料がフローセルに導入されたときの透過光量スペクトルを測定し、光量変化から各波長における吸光度を計算し、吸光度スペクトルを得る。   The principle of absorbance measurement of the diode array detector for liquid chromatograph will be described with reference to the block diagram of FIG. The light source light emitted from the light source 11 is condensed by the condenser mirror 12 and introduced into and transmitted through the flow cell 13. The light transmitted through the flow cell is introduced into the slit 15 by the condenser lens 14, and the light dispersed at each wavelength by the diffraction grating 16 is detected by the photodiode array detector 17 to obtain the transmitted light amount spectrum at each time point. Is stored in the PC data processing unit 18. The transmitted light amount spectrum when the sample is introduced into the flow cell is measured with reference to the transmitted light amount spectrum before introducing the sample components, and the absorbance at each wavelength is calculated from the change in the light amount to obtain the absorbance spectrum.

本発明を適用したフローセルの構造を図3に示す。フローセル流路21の内壁部を多孔質膜22にて被覆し、移動相24を流路に流すと、多孔質膜の屈折率<移動相の屈折率の場合に入射光23の入射角が多孔質膜の屈折率と移動相の屈折率から定まる臨界角より大きい場合に界面にて全反射が起こる。反射された光は再びフローセル内壁面に到達し、入射角が臨界角よりも大きければ再び全反射を起こし、これを繰り返してフローセル流路の軸方向に伝搬し、流路の出射側端面から出射される。全反射は反射率100%のため、移動相での吸収や散乱以外は損失なく透過する。   The structure of the flow cell to which the present invention is applied is shown in FIG. When the inner wall of the flow cell channel 21 is covered with the porous film 22 and the mobile phase 24 is allowed to flow through the channel, the incident angle of the incident light 23 is porous when the refractive index of the porous film <the refractive index of the mobile phase. Total reflection occurs at the interface when the critical angle determined from the refractive index of the membrane and the refractive index of the mobile phase is larger. The reflected light reaches the inner wall of the flow cell again. If the incident angle is larger than the critical angle, total reflection occurs again. This is repeated and propagates in the axial direction of the flow cell, and exits from the exit end face of the flow channel. Is done. Total reflection has a reflectance of 100%, so that it transmits without loss except for absorption and scattering in the mobile phase.

多孔質膜はSiO2の微粒子(粒径約10nmの球状粒子が数個数珠つなぎになったもの)を材料とし、これをバインダーとともに溶剤に溶かしたものを被覆面に塗布し、乾燥させて作製する。材料粒子が屈曲したひも状であるため、乾燥により凝集しても材料粒子間に空隙が形成される。この空隙の大きさは約数nmから数十nmであり、膜全体に占める全空隙の体積の割合は約42%となった。この膜の屈折率は膜材料と空気の屈折率およびそれぞれの体積比にて決定され、1.5×(1−0.42)+1.0×0.42=1.29となりアモルファスフルオロポリマーの屈折率とほぼ同一となった。 The porous film is made of SiO 2 fine particles (a mixture of several spherical particles with a particle size of about 10 nm), dissolved in a solvent together with a binder, applied to the coated surface and dried. To do. Since the material particles have a bent string shape, voids are formed between the material particles even if they are aggregated by drying. The size of this void was about several nm to several tens of nm, and the ratio of the volume of all voids to the entire film was about 42%. The refractive index of this film is determined by the refractive index of the film material and air and the respective volume ratios, and is 1.5 × (1−0.42) + 1.0 × 0.42 = 1.29. The refractive index was almost the same.

この膜にてフローセル流路内壁を被覆し、移動相として水を送液した場合、低屈折率膜の屈折率(1.29)と水の屈折率(1.33)より臨界角は76°となり、この場合のフローセルに導入可能な光束の立体角は0.187srとなる。従来型のフォトダイオードアレイ検出器用フローセル(内径1.3mm、光路長10mm)における取込可能な光束の立体角は0.133srであり、入射可能な透過光束の立体角では従来型以上となる。光路長を従来比5倍の50mmとした場合、フローセル容量を従来型と同一とすると、内径は1.3×1/√5=0.58mmとなり、従来型のフローセルより導入できる光束が減少するが、照明光学系の倍率を小さくし、入射光の結像の大きさをフローセルの内径よりも小さくし、照明光を全てフローセルに導入すれば、光量にして約1.4倍、約0.84倍のベースラインノイズ改善となる。   When the inner wall of the flow cell channel is covered with this film and water is fed as a mobile phase, the critical angle is 76 ° from the refractive index (1.29) of the low refractive index film and the refractive index of water (1.33). In this case, the solid angle of the light beam that can be introduced into the flow cell is 0.187 sr. The solid angle of the incident light beam in the conventional photodiode array detector flow cell (inner diameter: 1.3 mm, optical path length: 10 mm) is 0.133 sr, and the solid angle of the incident transmitted light beam is greater than that of the conventional type. If the optical path length is 50 mm, which is five times that of the conventional type, and the flow cell capacity is the same as that of the conventional type, the inner diameter is 1.3 × 1 / √5 = 0.58 mm, and the luminous flux that can be introduced from the conventional type flow cell is reduced. However, if the magnification of the illumination optical system is reduced, the image size of incident light is made smaller than the inner diameter of the flow cell, and all the illumination light is introduced into the flow cell, the amount of light is about 1.4 times and about 0.0. The baseline noise is improved by 84 times.

一方、光路長は従来比で5倍であり、クロマトグラムピーク高さは5倍となるため、クロマトグラムピークのS/N比は6.0倍となり、本発明によるフローセル部の改良のみで6倍の高感度化が実現可能となる。   On the other hand, the optical path length is 5 times that of the conventional one, and the chromatogram peak height is 5 times, so that the S / N ratio of the chromatogram peak is 6.0 times. Double the sensitivity.

1 送液ポンプ
2、24 移動相
3 オートサンプラ
4 カラム恒温装置
5 分離カラム
6 ダイオードアレイ検出器
7、18 PCデータ処理部
11 光源
12 集光ミラー
13 フローセル
14 集光レンズ
15 スリット
16 回折格子
17 フォトダイオードアレイ検出器
21 フローセル流路
22 多孔質膜
23 入射光
DESCRIPTION OF SYMBOLS 1 Liquid feed pump 2, 24 Mobile phase 3 Autosampler 4 Column thermostat 5 Separation column 6 Diode array detector 7, 18 PC data processing part 11 Light source 12 Condensing mirror 13 Flow cell 14 Condensing lens 15 Slit 16 Diffraction grating 17 Photo Diode array detector 21 Flow cell flow path 22 Porous film 23 Incident light

Claims (7)

概円筒形の流路を有し、これに液体試料を格納し、この流路の一端面より流路の長手方向に光を入射し、他端面より出射された光を光検出光学系により液体試料の光の吸収を測定する液体クロマトグラフ用フローセルにおいて、流路内壁を多孔質膜にて被覆していることを特徴とする液体クロマトグラフ用フローセル。   It has a substantially cylindrical flow path, a liquid sample is stored in this, light enters from the one end face of the flow path in the longitudinal direction of the flow path, and the light emitted from the other end face is liquidated by a light detection optical system. A liquid chromatograph flow cell for measuring light absorption of a sample, wherein a flow channel inner wall is covered with a porous film. 請求項1において、多孔質膜とは空気にて充満された微細な空隙を内部に有する膜であることを特徴とする液体クロマトグラフ用フローセル。   2. The flow cell for liquid chromatography according to claim 1, wherein the porous membrane is a membrane having fine voids filled with air inside. 請求項2において、多孔質膜の屈折率が膜材料の屈折率と空気の屈折率との中間の値を持つことを特徴とする液体クロマトグラフ用フローセル。   3. The flow cell for liquid chromatography according to claim 2, wherein the refractive index of the porous film has an intermediate value between the refractive index of the film material and the refractive index of air. 請求項3において、多孔質膜の屈折率が水の屈折率よりも小さいことを特徴とする液体クロマトグラフ用フローセル。   4. The flow cell for liquid chromatography according to claim 3, wherein the refractive index of the porous film is smaller than the refractive index of water. 請求項4において、水とほぼ同じ屈折率を持つ液体試料を格納した場合に流路に入射した光が多孔質膜にて被覆された内壁面で全反射し、試料による吸収および拡散分以外は損失なく流路内を伝播することを特徴とする液体クロマトグラフ用フローセル。   In claim 4, when a liquid sample having substantially the same refractive index as water is stored, the light incident on the flow path is totally reflected by the inner wall surface covered with the porous film, except for absorption and diffusion by the sample. A flow cell for liquid chromatography, which propagates through a flow path without loss. 請求項2において、多孔質膜の表面に接触した液体が空隙に浸入することを防止するための保護層を有することを特徴とする液体クロマトグラフ用フローセル。   3. The liquid chromatograph flow cell according to claim 2, further comprising a protective layer for preventing the liquid in contact with the surface of the porous membrane from entering the void. 請求項6において、保護層の厚さが100nm以下であることを特徴とする液体クロマトグラフ用フローセル。   The flow cell for liquid chromatography according to claim 6, wherein the thickness of the protective layer is 100 nm or less.
JP2011232443A 2011-10-24 2011-10-24 Flow cell for liquid chromatograph Pending JP2013088412A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2021024360A1 (en) * 2019-08-05 2021-02-11
CN114563515A (en) * 2020-11-27 2022-05-31 株式会社岛津制作所 Structure of flow cell module for chromatography detector and method for manufacturing capillary tube
CN114577965A (en) * 2022-03-25 2022-06-03 陕西周源光子科技有限公司 Photoelectric detection system for liquid chromatograph

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2021024360A1 (en) * 2019-08-05 2021-02-11
WO2021024360A1 (en) * 2019-08-05 2021-02-11 株式会社島津製作所 Detector for liquid chromatograph
JP7226561B2 (en) 2019-08-05 2023-02-21 株式会社島津製作所 Liquid chromatograph detector
CN114563515A (en) * 2020-11-27 2022-05-31 株式会社岛津制作所 Structure of flow cell module for chromatography detector and method for manufacturing capillary tube
CN114563515B (en) * 2020-11-27 2023-09-29 株式会社岛津制作所 Structure of flow cell assembly for chromatographic detector
CN114577965A (en) * 2022-03-25 2022-06-03 陕西周源光子科技有限公司 Photoelectric detection system for liquid chromatograph

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