DE202011002150U1 - filtration tank - Google Patents

Abstract

Filtration container (1), in particular for the concentration of macromolecules, which can be inserted into a filtrate recovery tube (5), with an upper section (2), a middle section (3) axially adjoining the upper section (2) and an axially adjoining section the middle section (3) adjoining lower section (4), of which - the upper section (3) forms a sample container (8) which is designed as a hollow cylinder or as a hollow truncated cone and an inlet opening (10) on its upper end face (9) - the downwardly tapering middle section (3) has a filtration chamber (13) which has at least one flat first main wall (14) tapering downwards relative to the opposite main wall (15), the at least one flat main wall (14) has a filter window (18) which is tightly closed by a flat membrane filter (19) and - the lower section (4) is attached to the lower edge (21) of the filter window ters (18) in the vertical direction downwards ...

Description

Field of the invention

• – der obere Abschnitt einen Probenbehälter bildet, der hohlzylindrisch oder als hohler Kegelstumpf ausgebildet ist und an seiner oberen Stirnseite eine Einlassöffnung aufweist,
• – der sich nach unten hin verjüngende mittlere Abschnitt eine Filtrationskammer, die mindestens eine nach unten hin relativ auf die gegenüberliegende Wand zulaufende ebene erste Hauptwand aufweist, wobei die wenigstens eine ebene Hauptwand ein Filterfenster aufweist, das durch einen flächigen Membranfilter dicht verschlossen ist und
• – der untere Abschnitt eine sich an die Unterkante des Filterfensters in vertikaler Richtung nach unten anschließende Retentatkammer bildet.

The invention relates to a filtration container, in particular for the concentration of macromolecules, which can be inserted into a filtrate recovery tube, with an upper portion, an axially adjoining the upper portion middle portion and an axially adjacent to the middle portion lower portion, of which

• The upper section forms a sample container which is hollow-cylindrical or formed as a hollow truncated cone and has an inlet opening at its upper end face,
• - The downwardly tapering central portion of a filtration chamber having at least one downwardly relative to the opposite wall tapering planar first main wall, said at least one planar main wall having a filter window which is sealed by a flat membrane filter and
• - The lower portion forms a subsequent to the lower edge of the filter window in the vertical direction down retentate.

State of the art

A concentration of macromolecules, in particular of protein samples, is carried out in a volume range of 500 μl to 20 ml in filtration containers, which are placed in a filtrate recovery tube and concentrated in centrifugal units by the ultrafiltration method. In ultrafiltration, it is common practice to provide a retentate chamber as a so-called dead-stop pocket in the filtration containers to prevent dry running of the sample. In this case, the concentrated sample is collected in the dead volume formed by the retentate chamber and recovered by pipetting. For some applications, such as For example, in protein crystallography, it is important to get a constant volume after concentration for all samples. In the known filtration tanks, this is not possible because the dead-stop pockets of the filtration tanks are adjacent to the membrane, which has been either adhesively or thermally attached to the housing. Heat or glue locally changes the permeability of the membrane so that it is tight in a tolerance range and thus increases the volume of the dead-stop bag.

From the EP 0 651 675 B1 For example, there is known a filtration container for the concentration of macromolecules that collects the concentrated macromolecules in conjunction with a filtrate recovery tube and a microconcentrator for concentrating macromolecules from a solution by rotating the microconcentrator in a centrifuge in a retentate container.

The known filtration tank consists of an upper portion, an axially adjoining the upper portion central portion and an axially adjacent lower portion. The upper portion forms a sample container, which is formed as a hollow cylinder, and the downwardly tapered central portion forms a filtration chamber having two opposing downwardly converging main walls and two connecting them at their lateral edges connecting walls.

One of the main walls forms a filter window for receiving a laminar membrane filter. The adjoining lower section forms a retentate chamber adjoining the lower edge of the filter window, the limiting main and connecting walls of which are planar extensions of the main and connecting walls of the middle section.

Although this known device has basically proven itself, it has been found that it is very difficult to obtain a constant volume after concentration for all samples.

Furthermore, from the JP 62-011564 A1 a filtration vessel for the centrifugal concentration of macromolecules known. A substantially hollow cylindrical container has a cylindrical insert which divides the container in the longitudinal direction and has a sealing collar. Above the covenant, an obliquely cut approach is arranged, whose inlet opening is covered by a filter membrane, which thus rises by an angle between 25 and 45 °. In this case, an annular retentate chamber is formed between the attachment and the surrounding container wall, in which the retentate is collected.

Even with this device, the volume of the dead-stop pocket, which is also adjacent to the boundary region to the membrane here, can increase in a tolerance range by changing the membrane permeability due to adhesive or thermal action.

task

It is therefore an object of the present invention to provide a filtration tank which has a retentate chamber which makes it possible to set a constant volume after concentration in the retentate chamber.

Presentation of the invention

This object is achieved in conjunction with the preamble of claim 1, characterized in that the filter window arranged in the first flat main wall is formed to be tapering towards its lower edge adjacent to the retentate chamber.

Due to the tapering design of the filter window, a negligibly small membrane surface lies directly above the retentate chamber bounded by the lower edge of the filter window. The volume of the retentate is always the same and thus reproducible by their inventive design of filtration tank to filtration tank.

According to a preferred embodiment of the invention, the filter window runs pointed towards its lower edge. Thus, the active membrane with the lower edge of the window has practically only a point contact with negligible membrane area and thus does not lead to a distortion of the retentate volume.

According to a further preferred embodiment of the invention, the flat membrane filter on its side facing away from the filtration chamber on a filter cover with at least one filtrate channel.

According to a further preferred embodiment of the invention, the filter cover is designed as an adapted to the outer shape of the filtration chamber überverschbare sleeve. By using an over-pushable sleeve, the membrane can be mechanically stabilized in the filter window during centrifugation.

According to a further preferred embodiment of the invention, the planar main wall and the opposite wall of the filtration chamber converge toward one another. Due to the converging main walls, the emergence or the formation of a small volume retentate chamber is favored.

In accordance with a further preferred embodiment of the invention, the first main wall of the filtration chamber is connected to an adjacent first main wall of the retentate chamber by means of a sloping slope relative to a horizontal extending transversely to a longitudinal axis. The sloping slope has an angle of greater than or equal to 30 ° relative to the horizontal. Preferably, the sloping slope with respect to the horizontal at an angle of about 45 °.

According to a further preferred embodiment of the invention, at least the retentate chamber is formed from a chemically inert material, in particular from the polymer polystyrene. Polystyrene has the advantage that it is chemically inert and has no protein binding properties. As a result of the construction according to the invention, the collection of the concentrated sample or of the retentate is made possible in a very small volume space, which is also chemically inert.

Further details of the invention will become apparent from the following detailed description and the accompanying drawings, in which preferred embodiments of the invention are illustrated, for example.

Brief descriptions of the drawings

In the drawings show:

1 FIG. 3: an exploded view of a filtration tank with filtrate recovery tubes, FIG.

2 : a side view in section of the filtration tank of 1 inserted into the filtrate recovery tube of 1 and

3 : an enlarged view of detail III of 2 ,

Description of the embodiments

A filtration tank 1 consists essentially of an upper section 2 , a middle section 3 and from a lower section 4 ,

The filtration tank 1 is in a filtrate recovery tube 5 used. Here is the filtration tank 1 with a cap 6 closed, according to the embodiments of the 1 to 3 via a connecting part 7 is formed.

The upper section 2 forms a sample container 8th which is formed substantially hollow cylindrical or as a hollow truncated cone and at its upper end side 9 an inlet opening 10 having.

At its upper end 9 the lower end is the upper section 2 in the middle section 3 above. The middle section 3 tapers downwards in a vertical plane and forms a filtration chamber 13 , the two main walls facing each other down towards each other 14 and 15 having. In the embodiments, the first main wall is 14 just trained while the second main wall 15 is concave inside in cross-section.

In the first flat main wall 14 is a filter window 18 arranged on his the filtration chamber 13 facing away from a filter cover 31 with a flat membrane filter 19 is covered tightly.

The filter window 18 has a transverse to the longitudinal axis 20 of the filtration tank 1 running lower edge 21 on, to which the lower section 4 connects in vertical direction downwards. That in the first flat main wall 14 arranged filter windows 18 is to his the retentate chamber 22 adjacent lower edge 21 formed tapering. This will run the filter window 18 laterally delimiting edges 32 . 33 pointed towards each other.

The lower section 4 forms a retentate chamber 22 with a first flat main wall 23 and an opposite second, semicircular or concave main wall 24 ,

The first main wall 14 the filtration chamber 13 is across one opposite one transverse to the longitudinal axis 20 extending horizontal 27 at an angle 28 slope of about 45 ° 29 with the adjacent first main wall 23 the retentate chamber 22 connected. The retentate chamber 22 is going down in a vertical direction from a ground 30 limited.

The retentate chamber forms for receiving the concentrated sample 22 below the lower edge 21 a retentate volume 34 (Dead space).

The filter cover 31 has at least one filtrate channel 35 on, over that through the membrane filter 19 passing filtrate into the filtrate recovery tube 5 is directed. The filter cover 31 is as one to the outer shape of the of the filtration chamber 13 formed middle section 4 adapted überiebbare sleeve formed The filtration tank 1 is preferably formed from the polymer polystyrene.

LIST OF REFERENCE NUMBERS

1

filtration tank

2

upper section of 1

3

middle section of 1

4

lower section of 1

5

filtrate recovery

6

cap

7

connecting part

8th

sample container

9

upper end of 2

10

Inlet opening of 2

11

Outer wall of 2

12

Inner wall of 5

13

Filtration chamber of 3

14

first main wall of 3

15

second main wall of 3

18

Filter window of 14

19

membrane filter

20

Longitudinal axis of 1

21

Lower edge of 18

22

retentate

23

first main wall of 22

24

second main wall of 22

27

horizontal

28

angle

29

slope

30

Ground of 22

31

filter cover

32

Edge of 18

33

Edge of 18

34

retentate

35

filtrate

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0651675 B1 [0003]
• JP 62-011564 A1 [0007]

Claims (10)

Filtration container ( 1 ), in particular for the concentration of macromolecules, which is introduced into a filtrate recovery tube ( 5 ), with an upper section ( 2 ), one axially to the upper portion ( 2 ) subsequent middle section ( 3 ) and one axially to the middle section ( 3 ) subsequent lower section ( 4 ), of which - the upper section ( 3 ) a sample container ( 8th ), which is formed as a hollow cylinder or as a hollow truncated cone and at its upper end face ( 9 ) an inlet opening ( 10 ), the downwardly tapering middle section (FIG. 3 ) a filtration chamber ( 13 ) having at least one downwardly relative to the opposing main wall ( 15 ) tapering plane first main wall ( 14 ), wherein the at least one planar main wall ( 14 ) a filter window ( 18 ), which by a flat membrane filter ( 19 ) is tightly closed and - the lower section ( 4 ) one to the lower edge ( 21 ) of the filter window ( 18 ) in the vertical direction down subsequent retentate ( 22 ), characterized in that in the plane first main wall ( 14 ) arranged filter window ( 18 ) to its retentate chamber ( 22 ) adjacent lower edge ( 21 ) is tapered towards. Filtration container according to claim 1, characterized in that the filter window ( 18 ) to its lower edge ( 21 ) pointed. Filtration container according to claim 1 or 2, characterized in that the flat membrane filter ( 19 ) on its filtration chamber ( 13 ) facing away from a filter cover ( 31 ) with at least one filtrate channel ( 35 ) having. Filtration container according to claim 3, characterized in that the filter cover ( 31 ) as one to the outer shape of the filtration chamber ( 13 ) adapted sliding sleeve is formed. Filtration container according to one of claims 1 to 4, characterized in that the planar main wall ( 14 ) and the opposite main wall ( 15 ) of the filtration chamber ( 13 ) converge. Filtration container according to one of claims 1 to 5, characterized in that the first main wall ( 14 ) of the filtration chamber ( 13 ) via one opposite one transverse to a longitudinal axis ( 20 ) extending horizontal ( 27 ) sloping slope ( 29 ) with an adjacent first main wall ( 23 ) of the retentate chamber ( 22 ) connected is. Filtration container according to claim 6, characterized in that the sloping slope ( 29 ) in relation to the horizontal ( 27 ) an angle ( 28 ) of greater than or equal to 30 °. Filtration container according to claim 7, characterized in that the sloping slope ( 29 ) in relation to the horizontal ( 27 ) an angle ( 28 ) of about 45 °. Filtration container according to one of claims 1 to 8, characterized in that at least the retentate chamber ( 22 ) is formed of a chemically inert material. Filtration container according to one of claims 1 to 9, characterized in that the retentate chamber ( 22 ) is formed from the polymer polystyrene.

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