JP2005024325A

JP2005024325A - Filtration member of sample for inspecting immunity

Info

Publication number: JP2005024325A
Application number: JP2003188067A
Authority: JP
Inventors: Takeshi Imoarai; 毅一口
Original assignee: Sysmex Corp
Current assignee: Sysmex Corp
Priority date: 2003-06-30
Filing date: 2003-06-30
Publication date: 2005-01-27
Anticipated expiration: 2023-06-30
Also published as: JP4199607B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a specimen pre-treatment method, capable of smooth inspection by preventing the clogging of a chromatographic membrane carrier by a sample, when performing immune chromatography. <P>SOLUTION: A sample, where a sampled specimen is pre-treated, is filtered by using a filtration member in which at least two types of membranes having a different membrane hole diameter are laminated. Then, the sample is smoothly filtered, and further a sample obtained by filtering can be subjected to immune chromatography, without causing clogging in the chromatographic membrane carrier. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明が属する技術分野】
本発明は、免疫クロマトグラフィー用検体前処理用部材に関する。より詳しくは、検体を前処理するための検体ろ過部材に関する。
【０００２】
【従来の技術】
従来から、抗原抗体反応を簡便に利用する方法として免疫クロマトグラフィーについて数多く報告されている（特許文献１〜３等）。これらに開示されている測定方法は、採取した検体を、目的とする抗体を含む検査器具に染み込ませるだけで、抗原の有無や量を知ることができる。この方法は、大別して展開型及びフロースルー型が挙げられる。
【０００３】
展開型は、ニトロセルロースなどの多孔質膜の一端に、目的とする被測定物質（例えば抗原）に対するリガンド（例えば特異抗体）を含み、多孔質膜の中程には同様に特定の被測定物質である抗原のみに結合する別の特異抗体を帯状に含む多孔質膜に固定されている。一端に含む特異抗体は、予め着色されており、その特異抗体が存在している多孔質膜の一端上に試料液を染み込ませるとサンプル液中に特異抗体と反応する被測定物質（抗原）があれば、その抗原は特異抗体と結び付いて着色粒子を付けた状態で多孔質膜を毛細管現象によってサンプル液を染み込ませた側と反対の片端へ向かって移動する。移動の途中で帯状に固定されている別の特異抗体の個所を通過する際に、抗原は多孔質膜上の特異抗体に捕捉され、多孔質膜上に帯状の染みが現れる。このことにより目的の抗原が試料中に存在していること及びその量を知ることができる。
【０００４】
一方、フロースルー型は、通常、上部開口部を有するコンテナーに吸収部材を収容するとともに当該吸収部材の上方に被測定物質と特異的に反応するリガンドを固定したクロマト用膜担体を設けた装置が用いられる。かかる装置を用いた被測定物質の測定は、例えば被測定物質が抗原の場合、上部開口部に被測定物質（即ち、抗原）液を加えて、被測定物質と特異的に反応するリガンド（即ち、抗体）を固定したクロマト用膜担体を通過させ、抗原を捕獲させる。次いで、上部開口部に、標識（例えば、酵素）を結合させた抗体液を添加することにより、当該抗体をクロマト用膜担体上に捕獲させた抗原と結合させ、更に標識に基づくシグナルを測定することにより抗原の測定が行われる。なお、クロマト用膜担体を通過した各液は、前記の吸収部材に吸収される。
【０００５】
免疫クロマトグラフィーの手法において、被測定物質を迅速、簡便かつ良好に検出しうるよう種々の検討がなされ、報告されている（特許文献４、５）。しかしながら、これらの報告は免疫クロマトグラフィー検査用テストストリップに関するものであって、検体前処理に関する報告ではない。
【０００６】
【先行文献】
【特許文献１】特開昭６１−１４５４５９号公開公報
【特許文献２】特開平６−１６０３８８号公開公報
【特許文献３】特開平６−５０９７３号公開公報
【特許文献４】特開２００２−３２８１２９号公開公報
【特許文献５】特開２００２−３２８１３０号公開公報
【０００７】
【発明が解決しようとする課題】
本発明は、免疫クロマトグラフィーを行う場合の、試料によるクロマト用膜担体の目詰まりを防ぎ、スムーズに展開しうる検体前処理方法を提供することである。
【０００８】
【課題を解決するための手段】
本発明者らは、種々検討し研究を重ねた結果、膜孔径が異なる膜を少なくとも２種類積層したもので検体処理液で処理した試料をろ過すると、スムーズにろ過され、更にろ過して得た試料もクロマト用膜担体の目詰まりを起こすことなくスムーズに免疫クロマトグラフィーが行われることを見出し、本発明を完成した。
【０００９】
即ち本発明は、
１．検体を前処理することにより調製された、免疫クロマトグラフィー用試料をろ過するためのろ過部材であって、膜孔径がクロマト用膜担体の膜孔径の１／１０〜１／１倍の孔径であるろ過膜（Ａ）と、膜孔径が（Ａ）の１０〜３０倍の孔径であるろ過膜（Ｂ）の少なくとも２種類のろ過膜を組み合せた構造からなることを特徴とするろ過部材、
２．検体を前処理することにより調製された、免疫クロマトグラフィー用試料をろ過するためのろ過部材であって、膜孔径が０．５〜５μｍのろ過膜と、膜孔径が１０〜５０μｍのろ過膜の少なくとも２種類のろ過膜を組み合せた構造からなることを特徴とするろ過部材、
３．更にガラスフィルターを組み合わせた構造からなる前項１又は２に記載のろ過部材、
４．鼻汁、痰又は咽頭ぬぐい液を検体として処理する前項１〜３のいずれか１に記載のろ過部材、
５．前記検体を前処理するための容器であって、前項１〜４のいずれか１に記載のろ過部材が装着されていることを特徴とする検体処理容器、
６．検体収容部及び試料排出口を有し、試料排出口と検体収容部との間に前項１〜４のいずれか１に記載のろ過部材が装着されており、更に、装着したろ過部材を構成するフィルターが検体収容部から試料排出口に向かって膜孔径が大きいものから順に積層されていることを特徴とする検体処理容器、
７．前項６に記載のろ過部材を装着した試料排出口を有するノズルが、検体収容部と取り外し可能な構造からなる検体処理容器、
８．前項５〜７のいずれか１に記載の検体処理容器を使用する検体の処理方法、
９．前項５〜７のいずれか１に記載の検体処理容器を含む免疫クロマトグラフィー用検査キット、からなる。
【００１０】
【発明の実施の形態】
（免疫クロマトグラフィー）
免疫クロマトグラフィーの手法は既に公知であるが、大別して、展開型及びフロースルー型等がある。本発明のろ過部材でろ過した試料は何れの型の免疫クロマトグラフィーにも適用することができる。
【００１１】
展開型免疫クロマトグラフィーのテストストリップの一例の概略図を図１に示し、その原理を説明する。ここで、テストストリップとは、免疫クロマトグラフィーが実際に行われる本体を意味し、必要に応じて試料添加部材、標識保持部材、クロマト用膜担体、検出捕獲部位、吸収部材等を備えたものをいう。図１の標識保持部材２に被測定物質である抗原に対するリガンド（即ち抗体）を標識した着色粒子を保持させ、検出部位４に、例えば前記抗原の部位を認識する抗体を固定する。図１の試料添加部材１に上記の処理した検体を試料として滴下し、クロマト用膜担体３を介して吸収部材５の方向に試料を展開させる。検体中に被測定物質である抗原）が存在している場合には、該抗原と検出部位４に固定した抗体とが抗原抗体反応し、標識が反応することで検出部位４の位置にシグナルとしてバンドが現れる。検出部位４に現れたバンドの色調等により、検体中に含まれる被測定物質の量を概略的に把握することができる。なお、標識として酵素、放射性物質、蛍光物質等が利用できることや標識に基づくシグナルの測定法はこの分野で周知である。
【００１２】
更に、フロースルー型免疫クロマトグラフィーの反応装置の一例の概略図を図２に示し、その原理を説明する。図２に示される反応装置は、プラスチック等からなる円筒状のコンテナー６に、吸収部材５（例えば、ガラス繊維等）が収容されており、当該吸収部材５の上方にはクロマト用膜担体３が設けられており、更にコンテナー６は上部に開口部７を有する構成となっている。かかる構成からなる反応装置を使用して被測定物質を測定する方法の一例として、被測定物質である抗原を測定する例の概略を説明する。まず、被測定物質である抗原を含有する試料液を試料添加部位である開口部７に供給する。試料液は、抗体（モノクローナル抗体又はポリクローナル抗体）を保持（感作）させたクロマト用膜担体３を通過し、被測定物質である抗原は当該クロマト用膜担体３に捕獲されると共に通過した試料液は吸収部材５に吸収される。次いで、被測定物質に反応する標識された抗体を供給し、クロマト用膜担体３に捕獲された抗原と該標識抗体を結合させる。その後、開口部７から適当な洗浄液を供給してクロマト用膜担体３を洗浄し、常法に準じて標識に基づくシグナルを測定することにより抗原（被測定物質）を測定（定量又は定性）することができる。なお、標識として酵素、放射性物質、蛍光物質等が利用できることや標識に基づくシグナルの測定法も、展開型免疫クロマトグラフィーと同様にこの分野で周知である。
【００１３】
（検体）
本発明において、被測定検体は特に限定されるものではなく、免疫クロマトグラフィーの手法により測定可能な被測定物質を含む可能性のあるものであれば良い。具体的には、例えば、唾液、血液、血漿、血清、尿、汗、涙、鼻汁、痰及び／又は咽頭ぬぐい液等の体液が挙げられる。例えば被測定物質としてインフルエンザウイルスを混入しうるものの例として、鼻汁、痰及び／又は咽頭ぬぐい液などが挙げられる。これらの検体を採取する方法は、特に限定されず、公知の方法を採用することができる。具体的には、綿棒を用いて、鼻汁、痰及び／又は咽頭ぬぐい液を採取することができる。
【００１４】
（検体処理）
上記免疫クロマトグラフィーの手法を利用できる試料は、原理上、多孔質膜であるクロマト用膜担体を毛細管現象によって通過できなければならない。しかし、鼻汁や咽頭ぬぐい液は、これらに存在する高粘性物質であるムチンが多孔質膜の膜孔を塞ぎ、またムチンは生体から剥がれ落ちた上皮付着細胞を凝集させるため、これらの物質により多孔質膜の孔が塞がれて検査を行うことができない。そこで、検体を検体処理液を用いて前処理しておくことにより、検査に不要な成分を予め除去しておくことが好ましい。かかる検体処理液は、一般的に使用されるものであれば良く特に限定されないが、反応に至適なｐＨである５〜９に保持うる緩衝液を構成する成分や、その他の適切な有機酸などを含ませることができ、例えば０．３ｖ／ｖ％ＮＰ４０，０．１５ＭＮａＣｌ及び１０ｍＭジチオスレイトール等を含有する１００ｍＭクエン酸緩衝液（ｐＨ６．０）を使用することができる。検体の処理は、検体処理液０．５〜１．０ｍＬに対して検体０．１〜０．２ｍＬを加え、よく振り混ぜで混和することにより行う。同様に鼻汁などの検体を採取した綿棒を検体処理液に浸し、検体処理液と検体をよく混和することにより行うことができる。検体の処理は、例えば検体処理容器に検体処理液を加えて行うことができる。本明細書では検体を処理液で処理したものを、便宜上「試料」という。更に、検体処理液で処理した試料をろ過することで、検査に不要な成分を予め除去することができる。
【００１５】
（ろ過部材）
上記検体処理液で処理した試料のろ過は、ろ過部材を通すことにより行うことができる。本発明のろ過部材は、膜孔径の異なるろ過膜を少なくとも２種類積層したものを含むものである。試料は、上記説明したようにクロマト用膜担体を毛細管現象により移動するものであるから、ろ過された試料の大きさはクロマト用膜担体の膜孔径よりも同等以下となることが必要である。通常、クロマト用膜担体の膜孔径は３〜１２μｍである。
【００１６】
上記の条件を満たしうるろ過部材を構成するろ過膜のひとつ（Ａ）の膜孔径は、クロマト用膜担体の膜孔径の１／１０〜１／１倍とすることができ、好ましくは１／６〜１／２倍とすることができる。また、他のろ過膜（Ｂ）の膜孔径は、（Ａ）の膜孔径の１０〜３０倍、好ましくは１５〜２５倍とすることができる。
他の態様として、ろ過部材を構成するろ過膜のひとつ（Ａ）の膜孔径は、０．３〜１２μｍとすることができ、好ましくは０．５〜１．５μｍとすることができる。また、他のろ過膜（Ｂ）の膜孔径は、５〜５０μｍ、好ましくは１５〜３０μｍとすることができる。
【００１７】
本発明のろ過部材は、（Ａ）及び（Ｂ）のろ過膜のほかに、更に（Ａ）及び（Ｂ）のろ過膜よりも膜孔径が大きいガラスフィルターを組み合わせることができる。また、ガラスフィルターに加えて他のろ過材を適宜組み合わせることもできるし、ガラスフィルターの他に、他のろ過材を適宜組み合わせることもできる。
上記のろ過部材を構成するろ過膜は、その膜孔径が試料が最初に通過するほうが大きく、試料が排出される方向に対して順次小さいものを重ね合わせる。そうすることで、検体処理液で処理した試料のろ過をスムーズに行うことができる。
【００１８】
本発明のろ過部材は、試料をろ過することができる態様であれば、特に限定されず使用することができる。例えば、検体処理容器に組み合わせて設けることができる。
【００１９】
（キット）
また、本発明は、上記ろ過部材及び該ろ過部材を含む検体処理容器にも及ぶ。更に、上記ろ過部材又はろ過部材を含む検体処理容器を含む免疫クロマトグラフィーに必要な試薬を含む検出キットにも及ぶものである。具体的には、前処理液、免疫クロマトグラフィー用デバイス、免疫クロマトグラフィー装置、各種抗体を含む試薬等が含まれるもの等が例示される。
【００２０】
【実施例】
本発明の理解のために、以下に図を基にした実施例を示して説明するが、本発明はこれら実施例に限定されるものではない。
【００２１】
（実施例１）検体処理
本実施例における検体処理容器及びろ過部材を図３及び４に示した。検体処理容器は、径１ｃｍ、高さ５ｃｍのプラスチックボトル８、試料通過口１２及び試料排出口１３を含むノズル９及びキャップ１０とから構成される。使用するまでは、ボトル内に検体処理液を約０．８ｍＬ含み、キャップ１０をした状態で保存されている。使用に際し、キャップ１０を開け、採取した検体０．１５ｍＬをボトル８内に加え、検体処理液と混和する。その後、キャップ１０の代わりに試料排出口１３を含むを含むノズル９をボトル８に装着し、上記の処理した試料を試料排出口１３から排出する。ノズル９の内側、試料排出口１３と試料通過口１２の間に、本発明のろ過部材１１を装着した（図４）。検体処理液で処理した後の試料は、試料通過口１２からろ過部材１１を経て、試料排出口１３から図１の試料添加部材１に滴下され、免疫クロマトグラフィーが行われる。
【００２２】
（実施例２）ろ過部材
実施例１で示したろ過部材１１を構成する膜は、膜孔径１．５μｍ厚さ０．４ｍｍのガラス繊維濾紙（ろ過膜ａ）、膜孔径２３μｍ厚さ０．４ｍｍのガラス繊維濾紙（ろ過膜ｂ）、厚さ０．７ｍｍのガラスフィルターである。また、ろ過膜ａからなるろ過部材（▲１▼）、ろ過膜ｂからなるろ過部材（▲２▼）、ガラスフィルターからなるろ過部材（▲３▼）、ろ過膜ａ及びろ過膜ｂを積層してなり試料通過口１２から試料排出口１３に向かってろ過膜ｂ、ろ過膜ａの順に積層されているろ過部材（▲４▼）、ろ過膜ａ、ろ過膜ｂ及びガラスフィルターを積層してなり、試料通過口１２から試料排出口１３に向かってガラスフィルター、ろ過膜ｂ、ろ過膜ａの順に積層されているろ過部材（▲５▼）を調製した。
【００２３】
（実験例１）
実施例２で示した▲１▼〜▲５▼の各種のろ過部材をノズル９に装着した検体処理容器を用いて、検体処理後ろ過した試料についてイムノクロマトグラフィーを行ったときの効果を調べた。
まず、０．３ｖ／ｖ％ＮＰ４０、０．４ＭＮａＣｌ及び１０ｍＭジチオトレイトールを含有する１００ｍＭクエン酸緩衝液（ｐＨ６．０）からなる検体処理液０．８ｍＬを含む検体処理容器８に、検体（鼻汁）０．１５ｍＬを加えて撹拌したものを試料とし、その後該試料をろ過した。約１００検体について試験を行い、ろ過部材（▲１▼）でろ過不能であった試料５検体（Ａ〜Ｅ）について各種ろ過部材の効果を検討した。その結果を表１にした。
【００２４】
【表１】

【００２５】
ろ過不能：試料をろ過する際に、膜の目詰まりにより、試験必要量が得られなかった。
判定不能：試料のろ過はできるが、測定において規定の判定時間になっても移動層が着色しており、判定が困難であった。
【００２６】
膜処理をしていない試料について試験を行った結果、クロマト用膜担体上で目詰まりを起こし、試料液の流れを阻害したため、判定ができなかった。
ろ過膜ａ単独では膜孔径が小さいために、試料をろ過する際に膜の目詰まりを起こし、ろ過することができなかった。
ろ過膜ｂ又はガラスフィルター単独では、膜孔径が大きすぎるため、試料は膜を素通りしてしまい、その結果、試料がクロマト用膜担体上で目詰まりを起こし、試料液の流れを阻害したため、判定ができなかった。
ろ過膜ａに、膜孔径の大きな膜を組み合わせることで、試料中の不溶物が段階的に取り除かれ、膜及びクロマト用膜担体上での目詰まりがなくなり、判定することができた。
【００２７】
【発明の効果】
以上詳述したように、本発明のろ過部材を用いて、検体をろ過すると、膜及びクロマト用膜担体上での目詰まりがなくなり、ろ過がスムーズに行われ、イムノクロマトグラフィーの検査がスムーズに行われることが確認された。
【図面の簡単な説明】
【図１】展開型の免疫クロマトグラフィー検査用テストストリップの概略を示す図である。
【図２】フロースルー型の免疫クロマトグラフィー検査用反応装置の一部を示す図である。
【図３】免疫クロマトグラフィー検査用検体処理容器の概略を示す図である。
【図４】図３の検体処理容器のうち、ノズル部分を説明する図である。
【符号の説明】
１試料添加部材
２標識保持部材（被測定物質に対する抗体標識着色粒子保持部）
３クロマト用膜担体
４検出部位（被測定物質に対する抗体固定部）
５吸収部材
６コンテナー
７開口部（試料添加口）
８検体処理用容器
９ノズル
１０キャップ
１１ろ過部材
１２試料通過口
１３試料排出口[0001]
[Technical field to which the invention belongs]
The present invention relates to a specimen pretreatment member for immunochromatography. More specifically, the present invention relates to a sample filtering member for preprocessing a sample.
[0002]
[Prior art]
Conventionally, many immunochromatography methods have been reported as methods for simply utilizing antigen-antibody reactions (Patent Documents 1 to 3 and the like). With the measurement methods disclosed in these publications, the presence / absence and amount of an antigen can be known simply by soaking the collected specimen into a test instrument containing the target antibody. This method is broadly classified into a deployment type and a flow-through type.
[0003]
The deployment type includes a ligand (for example, a specific antibody) for a target substance to be measured (for example, an antigen) at one end of a porous film such as nitrocellulose. Similarly, a specific substance to be measured is located in the middle of the porous film. It is fixed to a porous membrane containing another specific antibody that binds only to the antigen in a band shape. The specific antibody contained at one end is pre-colored, and when the sample solution is soaked on one end of the porous membrane where the specific antibody exists, a substance to be measured (antigen) that reacts with the specific antibody is contained in the sample solution. If present, the antigen moves to one end opposite to the side where the sample solution is impregnated by capillary action in a state where the antigen is combined with the specific antibody and colored particles are attached. When passing through the location of another specific antibody fixed in a band shape during the movement, the antigen is captured by the specific antibody on the porous membrane, and a band-like stain appears on the porous membrane. This makes it possible to know that the target antigen is present in the sample and its amount.
[0004]
On the other hand, the flow-through type is usually an apparatus in which an absorption member is accommodated in a container having an upper opening and a chromatographic membrane carrier in which a ligand that specifically reacts with a substance to be measured is fixed above the absorption member. Used. For example, when the substance to be measured is an antigen, a measurement substance (that is, an antigen) solution is added to the upper opening, and a ligand that specifically reacts with the substance to be measured (that is, an antigen) is measured. The antibody is passed through a chromatographic membrane carrier, and the antigen is captured. Next, an antibody solution to which a label (for example, an enzyme) is bound is added to the upper opening so that the antibody binds to the antigen captured on the chromatographic membrane carrier, and a signal based on the label is measured. Thus, the antigen is measured. Each liquid that has passed through the chromatographic membrane carrier is absorbed by the absorbing member.
[0005]
In the immunochromatography technique, various studies have been made and reported so that a substance to be measured can be detected quickly, conveniently and satisfactorily (Patent Documents 4 and 5). However, these reports relate to immunochromatographic test strips and not to specimen pretreatment.
[0006]
[Prior literature]
[Patent Document 1] Japanese Patent Laid-Open No. 61-14559 [Patent Document 2] Japanese Patent Laid-Open No. 6-160388 [Patent Document 3] Japanese Patent Laid-Open No. 6-50973 [Patent Document 4] Japanese Patent Laid-Open No. 2002-328129 [Patent Document 5] Japanese Unexamined Patent Application Publication No. 2002-328130
[Problems to be solved by the invention]
An object of the present invention is to provide a specimen pretreatment method that prevents clogging of a chromatographic membrane carrier due to a sample when performing immunochromatography and can be smoothly developed.
[0008]
[Means for Solving the Problems]
As a result of various studies and studies, the present inventors have obtained a sample obtained by filtering a sample treated with a specimen treatment liquid by laminating at least two kinds of membranes having different membrane pore diameters, and further filtering. It was found that immunochromatography can be carried out smoothly without clogging the chromatographic membrane carrier, and the present invention was completed.
[0009]
That is, the present invention
1. A filtration member for filtering a sample for immunochromatography prepared by pretreating a specimen, wherein the membrane pore size is 1/10 to 1/1 times the pore size of the chromatographic membrane carrier A filtration member characterized by comprising a structure in which at least two types of filtration membranes (A) and a filtration membrane (B) having a pore diameter 10 to 30 times that of (A) are combined.
2. A filtration member for filtering a sample for immunochromatography prepared by pretreating a specimen, comprising a filtration membrane having a membrane pore size of 0.5 to 5 μm and a filtration membrane having a membrane pore size of 10 to 50 μm A filtration member comprising a structure in which at least two types of filtration membranes are combined;
3. Furthermore, the filtration member according to the preceding

item

1 or 2, comprising a structure in which a glass filter is combined,
4). 4. The filtering member according to any one of items 1 to 3, wherein nasal discharge, sputum or throat swab is treated as a specimen.
5. A container for pre-processing the sample, wherein the filtering member according to any one of the preceding items 1 to 4 is mounted,
6). The filter member according to any one of the preceding items 1 to 4 is mounted between the sample discharge port and the sample storage unit, and further includes a mounted filter member. A sample processing container, wherein the filters are laminated in order from the membrane pore diameter toward the sample discharge port from the sample container;
7. A sample processing container having a structure in which a nozzle having a sample discharge port equipped with the filtration member according to item 6 is removable from the sample container;
8). A sample processing method using the sample processing container according to any one of 5 to 7 above,
9. The immunochromatography test kit comprising the sample processing container according to any one of 5 to 7 above.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
(Immunochromatography)
Immunochromatography techniques are already known, but broadly divided into a development type and a flow-through type. The sample filtered with the filtration member of the present invention can be applied to any type of immunochromatography.
[0011]
A schematic diagram of an example of a test strip for development type immunochromatography is shown in FIG. 1, and its principle will be described. Here, the test strip means a body in which immunochromatography is actually performed, and includes a sample addition member, a label holding member, a chromatographic membrane carrier, a detection capture site, an absorption member, and the like as necessary. Say. A colored particle labeled with a ligand (that is, an antibody) against an antigen as a substance to be measured is held on the label holding member 2 in FIG. The treated specimen is dropped as a sample onto the sample addition member 1 in FIG. 1, and the sample is developed in the direction of the absorption member 5 through the chromatographic membrane carrier 3. When an antigen as a substance to be measured is present in the sample, the antigen and the antibody immobilized on the detection site 4 undergo an antigen-antibody reaction, and the label reacts to produce a signal at the position of the detection site 4 A band appears. The amount of the substance to be measured contained in the specimen can be roughly grasped by the color tone of the band appearing at the detection site 4. Note that enzymes, radioactive substances, fluorescent substances, etc. can be used as labels, and methods for measuring signals based on labels are well known in this field.
[0012]
Further, a schematic diagram of an example of a flow-through type immunochromatographic reaction apparatus is shown in FIG. 2, and the principle thereof will be described. In the reaction apparatus shown in FIG. 2, an absorption member 5 (for example, glass fiber) is accommodated in a cylindrical container 6 made of plastic or the like, and a chromatographic membrane carrier 3 is placed above the absorption member 5. In addition, the container 6 is configured to have an opening 7 at the top. As an example of a method for measuring a substance to be measured using a reaction apparatus having such a configuration, an outline of an example of measuring an antigen as a substance to be measured will be described. First, a sample solution containing an antigen as a substance to be measured is supplied to the opening 7 as a sample addition site. The sample solution passes through the chromatographic membrane carrier 3 holding (sensitized) the antibody (monoclonal antibody or polyclonal antibody), and the antigen to be measured is captured and passed through the chromatographic membrane carrier 3 The liquid is absorbed by the absorbing member 5. Next, a labeled antibody that reacts with the substance to be measured is supplied, and the antigen captured on the chromatographic membrane carrier 3 is bound to the labeled antibody. Thereafter, an appropriate washing solution is supplied from the opening 7 to wash the chromatographic membrane carrier 3, and an antigen (substance to be measured) is measured (quantitative or qualitative) by measuring a signal based on the label according to a conventional method. be able to. Note that enzymes, radioactive substances, fluorescent substances, and the like can be used as labels, and methods for measuring signals based on labels are well known in this field, as in developmental immunochromatography.
[0013]
(Sample)
In the present invention, the sample to be measured is not particularly limited as long as it may contain a substance to be measured that can be measured by an immunochromatography technique. Specific examples include bodily fluids such as saliva, blood, plasma, serum, urine, sweat, tears, nasal discharge, sputum and / or throat swab. For example, nasal discharge, sputum and / or pharyngeal swab can be cited as examples of substances that can be contaminated with influenza virus as a substance to be measured. The method for collecting these specimens is not particularly limited, and a known method can be adopted. Specifically, nasal discharge, sputum and / or throat swab can be collected using a cotton swab.
[0014]
(Sample processing)
In principle, a sample that can use the immunochromatography technique must be able to pass through a chromatographic membrane carrier, which is a porous membrane, by capillary action. However, in nasal discharge and pharyngeal wiping fluid, mucin, which is a highly viscous substance present in them, blocks the pores of the porous membrane, and mucin aggregates epithelial adherent cells that have been detached from the living body. The pores of the membrane are blocked and inspection cannot be performed. Therefore, it is preferable to remove components unnecessary for the test in advance by pre-processing the sample with a sample processing solution. Such a sample treatment solution is not particularly limited as long as it is generally used. However, components constituting a buffer solution that can be maintained at 5 to 9 which is an optimum pH for the reaction, and other suitable organic acids. For example, a 100 mM citrate buffer (pH 6.0) containing 0.3 v / v% NP40, 0.15 M NaCl, 10 mM dithiothreitol, and the like can be used. The sample is processed by adding 0.1 to 0.2 mL of the sample to 0.5 to 1.0 mL of the sample processing solution and mixing by shaking well. Similarly, a cotton swab from which a sample such as nasal discharge is collected is immersed in the sample processing solution, and the sample processing solution and the sample are mixed well. The sample processing can be performed, for example, by adding a sample processing solution to a sample processing container. In this specification, a sample treated with a treatment liquid is referred to as a “sample” for convenience. Furthermore, by filtering the sample processed with the sample processing liquid, it is possible to previously remove components unnecessary for the inspection.
[0015]
(Filtration member)
The sample treated with the sample treatment liquid can be filtered by passing through a filtration member. The filtration member of the present invention includes a laminate in which at least two types of filtration membranes having different membrane pore diameters are laminated. Since the sample moves the chromatographic membrane carrier by capillary action as described above, the size of the filtered sample needs to be equal to or smaller than the membrane pore diameter of the chromatographic membrane carrier. Usually, the membrane pore diameter of the chromatographic membrane carrier is 3 to 12 μm.
[0016]
The membrane pore size of one of the filtration membranes (A) constituting the filtration member that can satisfy the above conditions can be 1/10 to 1/1 times the membrane pore size of the chromatographic membrane carrier, preferably 1/6. It can be set to ½ times. The membrane pore diameter of the other filtration membrane (B) can be 10 to 30 times, preferably 15 to 25 times the membrane pore diameter of (A).
As another aspect, the membrane pore diameter of one of the filtration membranes (A) constituting the filtration member can be 0.3 to 12 μm, and preferably 0.5 to 1.5 μm. The membrane pore diameter of the other filtration membrane (B) can be 5 to 50 μm, preferably 15 to 30 μm.
[0017]
In addition to the filtration membranes (A) and (B), the filtration member of the present invention can be combined with a glass filter having a larger membrane pore diameter than the filtration membranes (A) and (B). In addition to the glass filter, other filter media can be appropriately combined, and other filter media can be appropriately combined in addition to the glass filter.
The filtration membranes constituting the above-described filtration member are superposed with a membrane pore diameter that is larger when the sample first passes and is successively smaller than the direction in which the sample is discharged. By doing so, the sample processed with the sample processing liquid can be smoothly filtered.
[0018]
The filtration member of the present invention can be used without particular limitation as long as it can filter the sample. For example, it can be provided in combination with a sample processing container.
[0019]
(kit)
The present invention also extends to the filtration member and a sample processing container including the filtration member. Further, the present invention extends to a detection kit containing a reagent necessary for immunochromatography including the filtration member or the sample processing container including the filtration member. Specific examples include pretreatment liquids, devices for immunochromatography, immunochromatography apparatuses, and reagents containing various antibodies.
[0020]
【Example】
In order to understand the present invention, examples based on the drawings are shown and described below, but the present invention is not limited to these examples.
[0021]
Example 1 Sample Processing The sample processing container and the filtration member in this example are shown in FIGS. The sample processing container includes a plastic bottle 8 having a diameter of 1 cm and a height of 5 cm, a nozzle 9 including a sample passage port 12 and a sample discharge port 13 and a cap 10. Until use, the bottle contains about 0.8 mL of the sample processing solution and is stored with the cap 10 in place. In use, the cap 10 is opened, and 0.15 mL of the collected sample is added to the bottle 8 and mixed with the sample processing solution. Thereafter, the nozzle 9 including the sample discharge port 13 instead of the cap 10 is attached to the bottle 8, and the processed sample is discharged from the sample discharge port 13. The filtration member 11 of the present invention was mounted inside the nozzle 9 and between the sample discharge port 13 and the sample passage port 12 (FIG. 4). The sample after being treated with the sample treatment liquid is dropped from the sample passage port 12 through the filtration member 11 and from the sample discharge port 13 to the sample addition member 1 of FIG. 1, and immunochromatography is performed.
[0022]
(Example 2) Filtration member The membrane constituting the filtration member 11 shown in Example 1 is a glass fiber filter paper having a membrane pore diameter of 1.5 μm and a thickness of 0.4 mm (filtration membrane a), a membrane pore diameter of 23 μm and a thickness of 0.4 mm. Glass fiber filter paper (filtration membrane b), a glass filter having a thickness of 0.7 mm. In addition, a filtration member (1) made of filtration membrane a, a filtration member (2) made of filtration membrane b, a filtration member (3) made of glass filter, filtration membrane a and filtration membrane b were laminated. The filtration member (4), the filtration membrane a, the filtration membrane b, and the glass filter are laminated in this order from the sample passage port 12 to the sample discharge port 13 in the order of the filtration membrane b and the filtration membrane a. A filtration member (5) in which a glass filter, a filtration membrane b, and a filtration membrane a are laminated in this order from the sample passage port 12 toward the sample discharge port 13 was prepared.
[0023]
(Experimental example 1)
Using the sample processing container in which the various filtering members (1) to (5) shown in Example 2 were attached to the nozzle 9, the effect of performing immunochromatography on the sample filtered after the sample processing was examined.
First, a sample (nasal discharge) was placed in a sample processing container 8 containing 0.8 mL of a sample processing solution consisting of 100 mM citrate buffer (pH 6.0) containing 0.3 v / v% NP40, 0.4 M NaCl and 10 mM dithiothreitol. ) 0.15 mL was added and stirred as a sample, and then the sample was filtered. About 100 specimens were tested, and the effects of various filtration members were examined on five specimens (A to E) that could not be filtered with the filtration member (1). The results are shown in Table 1.
[0024]
[Table 1]

[0025]
Unfilterable: The required amount of the test could not be obtained due to clogging of the membrane when the sample was filtered.
Cannot be determined: Although the sample can be filtered, the moving layer is colored even when the specified determination time is reached in the measurement, and the determination is difficult.
[0026]
As a result of testing the sample not subjected to membrane treatment, it was not possible to judge because clogging occurred on the chromatographic membrane carrier and the flow of the sample solution was hindered.
Since the membrane pore diameter was small with the filtration membrane a alone, the membrane was clogged when the sample was filtered, and the membrane could not be filtered.
With the filter membrane b or the glass filter alone, the membrane pore size is too large, so the sample passes through the membrane, and as a result, the sample clogs on the chromatographic membrane carrier and inhibits the flow of the sample solution. I could not.
By combining a membrane having a large membrane pore size with the filtration membrane a, the insoluble matter in the sample was removed stepwise, and clogging on the membrane and the chromatographic membrane carrier was eliminated, and determination was possible.
[0027]
【The invention's effect】
As described in detail above, when the sample is filtered using the filtration member of the present invention, clogging on the membrane and the chromatographic membrane carrier is eliminated, the filtration is performed smoothly, and the immunochromatography test is performed smoothly. It was confirmed that
[Brief description of the drawings]
FIG. 1 is a diagram showing an outline of a development type immunochromatographic test strip.
FIG. 2 is a diagram showing a part of a flow-through type immunochromatographic test reactor.
FIG. 3 is a diagram showing an outline of a specimen processing container for immunochromatographic examination.
4 is a diagram for explaining a nozzle portion of the sample processing container of FIG. 3. FIG.
[Explanation of symbols]
1 Sample addition member 2 Label holding member (antibody-labeled colored particle holding part for the substance to be measured)
3 Chromatographic membrane carrier 4 Detection site (antibody immobilization part for analyte)
5 Absorbing member 6 Container 7 Opening (sample addition port)
8 Sample processing container 9 Nozzle 10 Cap 11 Filtration member 12 Sample passage port 13 Sample discharge port

Claims

A filtration member for filtering a sample for immunochromatography prepared by pretreating a specimen, wherein the membrane pore size is 1/10 to 1/1 times the pore size of the chromatographic membrane carrier A filtration member comprising a combination of at least two types of filtration membranes, a filtration membrane (A) and a filtration membrane (B) having a pore size 10 to 30 times that of (A).

A filtration member for filtering a sample for immunochromatography prepared by pretreating a specimen, comprising a filtration membrane having a membrane pore size of 0.5 to 5 μm and a filtration membrane having a membrane pore size of 10 to 50 μm A filtration member comprising a structure in which at least two types of filtration membranes are combined.

Furthermore, the filtration member of Claim 1 or 2 which consists of a structure which combined the glass filter.

The filtration member according to any one of claims 1 to 3, wherein nasal discharge, sputum or throat swab is treated as a specimen.

A sample processing container, which is a container for pretreating the sample, wherein the filtration member according to any one of claims 1 to 4 is mounted.

A filtration member according to any one of claims 1 to 4 is mounted between the sample discharge port and the sample storage unit, and further includes a mounted filtration member. The sample processing container is characterized in that the filters to be stacked are stacked in order from the sample containing portion toward the sample discharge port in descending order of the membrane pore diameter.

A sample processing container having a structure in which a nozzle having a sample discharge port on which the filtration member according to claim 6 is mounted is detachable from the sample container.

A sample processing method using the sample processing container according to any one of claims 5 to 7.

A test kit for immunochromatography comprising the sample processing container according to any one of claims 5 to 7.