DE202008003208U1 - Nutrient media unit for receiving a filter from a filtration device - Google Patents

Abstract

Nährmedieneinheit (14) for receiving a filter (4, 4 ') of a filtration device (1) with a filled with nutrient medium lower part (15, 15 ') and a lid (16), characterized in that the Cover (16) in the lower part (15, 15 ') projecting fixing edge (21) for removing the filter (4) from the filtration device (1) with an edge (13, 13 ') of the filter (4, 4') over a Adhesive adhesion (22) with the filter (4, 4 ') is connectable.

Description

Field of the invention

The The invention relates to a culture medium unit for receiving a filter of a filtration device with a nutrient medium filled lower part and a lid.

The is nutrient medium unit according to the invention for the microbiological examination of liquid samples previous filtration can be used, wherein a membrane filter of a filter support lifted and on a surface a nutrient base arranged in a lower part of a culture medium unit stored and the lower part is covered by a lid.

to microbiological analysis of liquids to be filtered or samples with a membrane filter after filtration of the Filter removed and, for example, in Petri dishes with a nutrient medium from agar loaded and covered with a lid, the Nährmedieneinheit in an incubator for several days at elevated temperature outsourced. About the culture medium may receive present microorganisms nutrients that contribute to growth so that they can be determined or counted.

State of the art

For example, from the DE 10 2005 008 220 B3 a filtration device with a arranged on a filter support of a device lower part membrane filter and an attachable to the device lower part essay known.

adversely in this device, which basically works well is that a special expandable extraction ring is necessary is taken with the membrane filter and into a cup-shaped Lower part of the culture medium unit is stored.

Furthermore, from the DE 198 23 993 B4 a disposable device for microbial determination in liquids with a pouring funnel, a microporous membrane with membrane support and a membrane support unit known, wherein the infusion funnel and the membrane support are fixable to each other and wherein at Ausgusstrichter at least one ejection device is provided for the membrane support and the membrane support and the ejection device of a membrane support unit be attacked releasably.

adversely It is that the filtration unit formed relatively expensive is and after filtration in a separate step over a defined pressure point the filter support can be solved got to. After that, in a second additional step the infusion funnel / membrane carrier unit over the opened lower part of the culture medium unit, d. H. the agar dish, positioned and by means of a second and offset by 90 ° pressure point the membrane on the nutrient medium be filed.

Furthermore, from the EP 0 150 775 B1 a device for the examination of a liquid sample by membrane filtration, in which the membrane filter is sealingly attached to the end of a sleeve. This sleeve end is designed so that it serves as a plug-in receptacle for a media container. The second end of the sleeve can be tightly closed with a lid to lock the membrane media unit into the incubator.

adversely this is a firm connection to the infuser, which requires that either a large dead volume is accepted or but additional handling steps to reduce the Dead volume by upsetting or even to separate the unit necessary.

Furthermore, from the US 2002/0096468 A1 a Nährmedieneinheit known, which is composed of parts of a filtration device. After a filtration process, a lid and a funnel are removed from a device base on which a filter is placed on a filter pad formed as a pad. The filter is permanently glued to the device lower part with a fixing edge, which acts as a seal. The lid of the attachment is now placed directly on the device lower part of the filtration device and device lower part and lid are turned with the filter, so that the lid forms a lower part. Subsequently, nutrient solution is fed via the drain of the device lower part and the drain is closed with a special plug. Only then can the device be placed in an incubator.

adversely in the known device is that the filtration device is relatively expensive due to the large number of parts and the Device lower part at least during an incubation period in the incubator not available for further filtration stands. As far as the filter is glued in the lower part of the device, Can not replace the filter pad, but only with a nutrient solution is relatively complicated be soaked. In this known device remains the filter thus either in the lower part of the filtration device or the filter is bspw in a known manner with a tool. taken from a pair of tweezers.

From the US 4 299 921 A is a nutrient media unit known between its lower part and ih Rem lid has a seal. The seal is attached either on the edge of the base or in the lid via an adhesive layer.

adversely in this known Nährmedieneinheit is that a filter introduced from a filtration device with, for example, a pair of tweezers must become.

task

task It is therefore an object of the present invention to provide a device where it is possible to filter after filtration without complicated filtration device and without the use of one additional aid simple and inexpensive into the nutrient media unit.

The the device or Nährmedieneinheit relevant task is in conjunction with the preamble of claim 1 thereby solved that the lid protruding into the lower part Has Fixierrand, the removal of the filter from the filtration device with an edge of the filter via an adhesive bond with the Filter is connectable.

Thereby, in that the lid has a fixing edge, which corresponds to a corresponding one Edge of the filter can be placed over an adhesive bond, The filter adheres to the lid and is easy and simple lift off the filter support and into the base bring in the nutrient media unit. It can on the one hand conventional uncomplicated filtration devices used and secondly, without any additional tools the filter are introduced into the culture medium unit.

To a preferred embodiment of the invention is the Adhesive adhesion formed temporarily or reversibly. Thereby can easily be removed from the filter after incubation or lifted off.

The Adhesive adhesion is in accordance with a preferred embodiment of the invention as an adhesive layer of a suitable adhesive and can at the fixing edge of the lid or at the corresponding edge of the Filters can be arranged. The power of adhesive adhesion can be chosen Be that a subsequent examination of the sample after incubation is possible by returning the filter from the nutrient medium or the fixing edge of the lid deducted and thus access to the has formed microbiological colonies.

To a further preferred embodiment of the invention is the adhesive layer of PSA dispersion adhesive or acrylate copolymer microspheres educated. As a result, wet filters are sufficient at the fixing edge the lid can be attached and also removed again. Suitable pressure-sensitive For example, adhesives are known to those skilled in the art as microsphere-based acrylate adhesives known.

According to one Another preferred embodiment is the adhesive layer executed in such a way that they are for the decrease the filter of the filtration device one possible has high adhesive strength and after contact with the wet filter and the humid nutrient medium with a time delay detachable is and the adhesive strength drops to zero. The needed Time offset results from the application. Must have several minutes the adhesive power for manipulating the filter is available after which it should fall to zero. At least at the end of the Incubation should be the fixing edge of the lid again from Be solvable filter. The end time of incubation is in the case of classical microbiology, if by eye visible colonies appear after about one day. The incubation period is usually set in standards and can last up to several days last for. In the case of rapid tests, the germs and microcolonies already be able to prove before, the adhesive power should be at the latest after about 1 h have fallen so far that the filter can be solved non-destructive from the fixing edge of the lid.

According to one preferred embodiment of the invention, this is time-shifted Adhesive-dissolving behavior through an intermediate layer of a water-soluble Realized connection under the adhesive layer. This detachable Layer is between Fixierrandoberfläche and adhesive layer applied so that the entire adhesive surface safely is underlaid by the releasable layer and also contact surfaces for the penetration of the water required for dissolution available. Such a function is z. Of gelatin Fulfills. The needed for the release Water is deposited on the agar surface after laying Diffuse agar. All chemicals used soluble Layer, as well as the adhesive allowed the intended Do not negatively affect the growth of microorganisms.

The water-soluble intermediate layer may also be on the lid edge and the adhesive layer may be disposed on the filter edge.

According to a further preferred embodiment of the invention, the fixing edge is formed by a free end face of an annular inner wall, which is arranged on the lower part facing the inner lid surface and projects into the lower part. The annular inner wall ensures on the one hand the necessary distance between filter and lid and on the other hand, its diameter in the dimension of the filter diameter is designed so that the filter only on its outer Edge comes into contact with the adhesive layer of the adhesive bond, wherein the edge is disposed outside of the filter surface used.

According to one Another preferred embodiment is the annular Inner wall designed so that the fixing surface not planar, but curved concavely to two predetermined sides so that in use the removal of the filter from the filter support one of these 2 pages will be solved first and so on the vacuum filtration remaining residual vacuum is still broken and the filter is easier to remove. Also when hanging up of the filter on the agar surface thus results positive effect, because with it the inclusion of air bubbles continues is reduced.

The Lower part of the nutrient unit is bowl-shaped trained and has a nutrient medium on which the Lid facing top of the adhesive on the cover filter can be stored is. After placing the cover on the lower part are the filter and The top of the medium and evenly spaced together. The lower part may for example be a Petri dish with Nutrient medium is filled. As nutrient media come filled agar based media as well as cardboard discs with aqueous nutrient media into consideration.

According to one Another preferred embodiment of the invention the top of the medium is convexly arched.

Thereby, that the nutrient medium or agar is convex, d. H. higher in the middle, has the filter or the membrane When placing first contact the center, so on further storage the air can escape to the outside and form no air bubbles. This is desirable because there are air bubbles between the filter and Nutrient medium could otherwise be enclosed, which could lead to a growth inhibition.

To Placing the lid on the bottom are the filter and the Top of the medium and evenly spaced together.

To a further preferred embodiment of the invention is concentric with the outer wall of the lower part of a Culture medium laterally supported in a lower area Support ring arranged, whose inner diameter is about the Outer diameter of the filter corresponds.

By the support ring is less agar used because only the Filter surface is underlaid with agar. The reinforcement ring has the further advantage that the surface of the nutrient medium or the Agarboden is easier to buckle. This embodiment also ensures that through the avoided contact of the glue to the agar, the adhesive properties can be changed by the agar.

According to one Another preferred embodiment of the invention the support ring is positioned and designed so that it by contact or closure against the adhesive layer the lid will change the adhesive properties during storage, for example by dehydration, reduced.

To a further preferred embodiment of the invention is the inner lid diameter of the outer wall of the lid chosen so that it is larger than that Outer diameter of the filter support of the filtration device. Preferably, the inner lid diameter of the outer wall the lid only slightly larger than the outer diameter the filter support. Thus, the lid when putting on led to the filter through the filter support, before the filter or the lid with the adhesive adhesion in contact comes. The correct positioning of the filter in the lid is thereby ensured.

In a further preferred embodiment, the annular Inner wall of the lid on an inner radius, the larger or equal to the inside sealing edge of the filtration funnel. Consequently is ensured during positioning that no Filtration surface covered and thus potentially Filtered germs are prevented from growing. Because commercial Filter (specified by international norm hints and suggestions) have a total diameter of 47 mm, the commercially available Filtration funnels in similar diameters offered, what this embodiment of the invention for the most part for all common Filtration funnel can be offered.

According to one Another preferred embodiment of the invention the adhesive bond between Fixierrand and filter interrupted in places. In a preferred embodiment, the fixing edge or the annular inner wall at least one recess on, through which an air exchange can take place. But it is also possible for example, by two recesses the annular Inner wall in at least two inner wall segments with end faces in the form of circular arc segments of variable length to divide. This circular arc segment-shaped end faces, the form in this embodiment, the fixing edge are over the adhesive layer of adhesive adhesion on the outside The edge of the filter can be fixed, the edge outside the used filter surface is arranged. The adhesive adhesion can on the circular arc segment-shaped end faces or be arranged on the corresponding edge of the filter.

In In another preferred embodiment, the at least two recesses designed so wide that the fixing edge or the annular inner wall on at least two pins is reduced, which form the fixing edge and its from the lid inner surface remote, free ends on the adhesive layer of adhesive adhesion can be fixed on the outer edge of the filter, the edge being outside the used filter surface is arranged. In a particularly preferred embodiment only the free ends of the fixing pins acted upon by the adhesive layer. By these two preferred embodiments is not only a saving on the annular inner wall forming material, but it is also an air exchange guaranteed.

It But it is also possible to use the cover for warranty an air exchange with a resealable gassing for fumigation of the filter surface to train for aerobic germs sufficient air exchange and thus the oxygen supply during the incubation.

Preferably the filters are designed as membrane filters.

According to one preferred embodiment of the invention is the lid on the filter support on the filter so be placed, that a arranged in the lid fixing edge with a Edge of the filter is connected via an adhesive bond, and that the lid with the adhesive filter from the filter support lifted and on the cup-shaped lower part of the Nährmedieneinheit is placed so that the lid facing away from the underside of Filters on the lid facing top of the medium rests.

Thereby, that the filter with the lid is arrested and the lid with lifted off the filter from the filter support and on the top of the arranged in the culture medium container Nutrient soil is added, additional Steps or devices avoided and the filter can without a additional tool in the bowl-shaped base the Nährmedieneinheit be spent. It can simple, conventional filtration devices used become.

So far the adhesive bond is located on the lid is not even one Modification of the filters necessary.

In order to results in a simple and inexpensive manipulation of the filter with the applied sample.

According to one preferred embodiment of the invention is an on the fixing edge of the lid applied water-soluble Interlayer dissolved and the lid can after a Incubation can be released again from the filter.

Further Features of the invention will become apparent from the following detailed Description and the accompanying drawings in which preferred Embodiments of the invention exemplified are.

Brief descriptions of the drawings

 In show the drawings:

1 : a side view of a filtration device in section,

2 a side view of the device lower part of 1 with filter and attached lid of a nutrient media unit in section,

3 FIG. 2: a side view in section of a lower part of a culture medium unit with attached cover and inserted filter, FIG.

4 FIG. 2: a side view of a filter with an adhesive layer in section and enlarged view, FIG.

5 : a side view of the lid of 3 with attached filter in section and enlarged view,

6 FIG. 2: a side view of a lower part of a nutrient media unit with convexly curved culture medium and support ring in section and enlarged representation, FIG.

7 : a soffit on the lid of 5 with an adhesive layer in an enlarged view,

8th a side view of another filtration device in section,

9 : a side view of a culture media unit without filter in section,

10 : a soffit on a lid accordingly 5 in an enlarged view with fixing pins,

11 : a soffit on a lid accordingly 5 in an enlarged view with inner wall segments and

12 : A side view of a lid with water-soluble intermediate layer, adhesive layer and adhering filter in section and Ausriss in enlarged erter representation.

Description of the embodiments

A filtration device 1 consists essentially of an essay 2 , a device base 3 and a filter 4 ,

The device base 3 has a filter support 5 on, on which the filter 4 is stored. The device base 3 still has a paragraph 6 for receiving the essay 2 on.

The essay 2 is as a funnel 7 formed, at its lower end in the vertical direction a cylindrical approach 8th which, with its inner lateral surface 9 about the paragraph 6 of the lower part 3 attacks. In the interior of the cylindrical approach 8th points the funnel 7 an outlet opening 10 on, acting as a stop against the device base 3 or opposite to that on the lower part 3 arranged filters 4 serves, on. The essay 2 or the funnel 7 can be compared to the lower part 3 over a detent 11 be locked.

The filter 4 consists of a membrane 12 with a filter edge 13 that is outside the outlet opening 10 is arranged.

According to the embodiment of 4 is the filter edge 13 of the filter 4 ' with a glue adhesion 22 Mistake.

After filtering the sample becomes the filter 4 . 4 ' into a nutrient media unit 14 brought in. The nutrient media unit 14 consists of a bowl-shaped base 15 , which may be formed as a Petri dish or an agar dish, and a lid 16 , In the lower part 15 is a breeding ground 17 , For example, from agar arranged.

According to the embodiment of 6 has the lower part 15 ' a support ring 18 on, the breeding ground 17 ' supported laterally. In the unloaded state is the top 19 . 19 ' of the nutrient medium 17 . 17 ' , which lies in a vertical direction at the top, convexly curved, so that the culture medium 17 . 17 ' towards the middle is a bit thicker.

The lid 16 is on the lower part 15 . 15 ' the nutrient media unit 14 placed. At his bottom 15 . 15 ' facing inner lid surface 20 points the lid 16 one in the lower part 15 . 15 ' protruding fixing edge 21 on, to remove the filter 4 . 4 ' from the filtration device 1 with the filter edge 13 of the filter 4 . 4 ' about the adhesive adhesion 22 with the filter 4 . 4 ' is connectable. The fixation margin 21 is from a free end face of a lid on the inner surface 20 arranged annular inner wall 23 educated.

Corresponding 7 is the adhesive adhesion 22 as an adhesive layer 27 from a suitable adhesive on the fixing edge 21 of the lid 16 arranged. But it is also possible, the adhesive layer according to 4 at the filter edge 13 ' to arrange.

The adhesive adhesion 22 between fixing edge 21 and filters 4 is interrupted in places to ensure air exchange. For this purpose, the inner wall 23 of the lid 16 on its end face or on the fixing edge 21 recesses 24 on. It is also possible on the support ring 18 recesses 26 to arrange. The adhesive layer of adhesive adhesion 22 is made of an adhesive PSA dispersion adhesive or of acrylate copolymer microspheres.

In a preferred embodiment according to 10 are the recesses 24 designed so wide that the annular inner wall 23 or the fixing edge 21 on at least two pins 29 is reduced, whose from the lid inner surface 20 remote, free ends on the adhesive layer of adhesive adhesion 22 on the outside edge 13 the filter are fixable, the edge 13 is arranged outside of the used filter surface. The free ends are here with the adhesive layer or adhesive adhesion 22 applied. In an alternative embodiment, not shown, have the fixing pins 29 no adhesive layer at their free ends. The adhesive layer is here at the edge of the filter 13 arranged. For stability reasons for the adhesion between filters 4 and lid 16 are at least two pins 29 intended. 10 shows three pins 29 , which are preferably arranged equidistantly on an imaginary circle circumference.

The embodiment of 11 shows an alternative embodiment of a lid 16 , its fixing edge 21 of two inner wall segments 28 with gaps between them 24 is formed.

For introducing the filter designed as a membrane filter 4 in the lower part 15 . 15 ' the nutrient media unit 14 becomes after filtering the essay 2 from the filter support 5 of the device base 3 lifted. Subsequently, the lid 16 from the lower part 15 . 15 ' the nutrient media unit 14 removed and on the on the filter support 5 lying filter 4 so put on that in the lid 16 arranged fixing edge 21 with the filter edge 13 of the filter 4 about the adhesive adhesion 22 is connected and the filter 4 on the lid 16 adheres. The lid 16 is then with the filter 4 from the filter support 5 lifted off and on the lower part 15 . 15 ' the nutrient media unit 14 placed. This is the lid 16 with the bottom 25 of the filter 4 on top 19 . 19 ' of the nutrient medium 17 . 17 ' hung up.

According to the embodiment of 12 is between the adhesive layer 27 the adhesive adhesion 22 and the fixing edge 21 of the lid 16 a water-soluble intermediate layer 30 applied from gelatin.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 102005008220 B3 [0004]
• - DE 19823993 B4 [0006]
• - EP 0150775 B1 [0008]
• US 2002/0096468 A1 [0010]
• US 4299921A [0012]

Claims (22)

Nutrient media unit ( 14 ) for receiving a filter ( 4 . 4 ' ) a filtration device ( 1 ) with a filled with nutrient medium lower part ( 15 . 15 ' ) and a lid ( 16 ), characterized in that the lid ( 16 ) one in the lower part ( 15 . 15 ' ) projecting fixing edge ( 21 ), which is used to remove the filter ( 4 ) from the filtration device ( 1 ) with a border ( 13 . 13 ' ) of the filter ( 4 . 4 ' ) via an adhesive bond ( 22 ) with the filter ( 4 . 4 ' ) is connectable. Culture medium unit according to claim 1, characterized in that the adhesive adhesion ( 22 ) is formed temporarily or reversibly. Culture medium unit according to claim 1 or 2, characterized in that the fixing edge ( 21 ) of the lid ( 16 ) an adhesive layer ( 27 ) has a suitable adhesive. Nutrient media unit according to claim 2 or 3, characterized in that the adhesive via a water-soluble intermediate layer ( 30 ) is applied to the fixing edge of the lid. Culture medium unit according to claim 1, characterized in that the filter edge ( 13 ) of the filter ( 4 ' ) an adhesive layer ( 27 ) has a suitable adhesive. Nutrient media unit according to claim 5, characterized in that the fixing edge ( 21 ) of the lid ( 16 ) a water-soluble layer ( 30 ) having. Culture medium unit according to one of claims 3 to 6, characterized in that the adhesive layer ( 27 ) is formed of a PSA dispersion adhesive or of acrylate copolymer microspheres. Culture medium unit according to one of claims 1 to 7, characterized in that the fixing edge ( 21 ) from a free end face of one of the lower part ( 15 . 15 ' ) facing inside lid surface ( 20 ) arranged annular inner wall ( 23 ) is formed. Nutrient media unit according to claim 8, characterized in that the fixing surface of the fixing edge ( 21 ) is concaved toward two predetermined sides. Culture medium unit according to one of claims 1 to 9, characterized in that the lower part ( 15 . 15 ' ) is cup-shaped and a nutrient medium ( 17 . 17 ' ) on which the lid ( 16 ) facing top ( 19 . 19 ' ) on the lid ( 16 ) adherent filters ( 4 . 4 ' ) can be stored. Nutrient media unit according to claim 10, characterized in that the upper side ( 19 . 19 ' ) of the nutrient medium ( 17 . 17 ' ) is convexly curved. Culture medium unit according to one of claims 8 to 9, characterized in that after placing the lid ( 16 ) on the lower part ( 15 . 15 ' ) the filter ( 4 ) and the top ( 19 . 19 ' ) of the nutrient medium ( 17 . 17 ' ) lie flat and without gaps. Culture medium unit according to one of claims 10 to 12, characterized in that in the lower part ( 15 ' ) concentric to the outer wall, the nutrient medium ( 17 ' ) supporting laterally in a lower region supporting ring ( 18 ) is arranged, whose inner diameter is approximately the outer diameter of the membrane filter ( 4 . 4 ' ) corresponds. Culture medium unit according to claim 13, characterized in that the support ring ( 18 ) is positioned and formed such that it can be brought into contact with the adhesive layer by contact or closure (FIG. 27 ) of the lid ( 16 ) reduces any change in adhesive properties during storage. Nutrient media unit according to one of claims 1 to 14, characterized in that the inner lid diameter of the outer wall of the lid ( 16 ) is selected so that it is greater than the outer diameter of a filter support of the filtration device ( 1 ). Nutrient media unit according to claim 15, characterized in that the inner lid diameter of the outer wall of the lid ( 16 ) is only slightly larger than the outer diameter of the filter support. Culture medium unit according to one of claims 1 to 16, characterized in that the adhesive adhesion ( 22 ) between fixing edge ( 21 ) and filters ( 4 ) is interrupted in places to ensure air exchange. Culture medium unit according to one of claims 1 to 17, characterized in that the fixing edge ( 21 ) of the lid ( 16 ) is interrupted by at least one recess for ensuring an air exchange. Culture medium unit according to one of claims 1 to 18, characterized in that the fixing edge ( 21 ) of the lid ( 16 ) on at least two pins ( 29 ), over which of the filters ( 4 ) with the lid ( 16 ) is connectable. Culture medium unit according to one of claims 1 to 16, characterized in that the lid ( 16 ) to ensure an air exchange has a resealable gassing. Culture medium unit according to one of claims 1 to 20, characterized in that the nutrient medium ( 17 . 17 ' ) is made of agar. Culture medium unit according to one of claims 1 to 21, characterized in that the filter ( 4 ) is formed as a membrane filter.