EP1075649A1

EP1075649A1 - Device for enriching particles in a body fluid

Info

Publication number: EP1075649A1
Application number: EP98944993A
Authority: EP
Inventors: Rainer Ballnath; Helmut Fromm
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-04-29
Filing date: 1998-07-16
Publication date: 2001-02-14
Also published as: AU9252598A; WO1999056104A1; DE19820178A1; JP2002513150A; DE19820178C2

Abstract

The invention relates to a device for enriching particles in a body fluid, especially for preparing an enriched suspension for analysis, comprising a receiving body (1), preferably a cylindrical receiving body, and a piston (2) arranged in the receiving body (1) in such a way that it can be displaced to draw in and discharge the fluid. The receiving body (1) has a pipette-like tapered suction/outlet opening (3). In order to simplify the use and construction of the device and avoid contamination of the operator with body fluid, the device is configured and embodied in such a way that a capture device (4) that catches or captures the particles is mounted in the flow path of the fluid being admitted into the receiving body (1) and/or being discharged from the receiving body (1).

Description

"Device for Enriching Particles in Body Fluid"

The present invention relates to a device for enriching particles in body fluid, in particular for providing an enriched suspension for analysis, with a preferably cylindrical receiving body and a piston which is displaceably arranged in the receiving body and is used for drawing in and expelling the liquid, the receiving body being a pipette-like has tapered suction / outlet opening.

Devices of the generic type have been known in practice for years. Reference is made to DE 37 19 302 C1 only by way of example. From this publication, a device for urine examination is known, specifically a device for microscopic quantitative urine sediment analysis. This device comprises a cylindrical receiving body or sample container which has an opening on one side and a pipette tip on the other side. A sample container is inserted into the receiving body. Furthermore, there is a tubular piston in the receiving body which is displaceable in a sealing manner, both the piston and the sample container being made of a transparent material. A stopper is used to close the sample container. A cap for the pipette tip is also provided. A one- or multi-stage filter arrangement is provided in the piston near the lower end, and is integrated in the piston.

The device known from DE 37 19 302 for the enrichment of particles in body fluid is extremely problematic to handle. First of all, it is necessary to lock the flask in the sample container when the cap is removed. Then the piston must be closed with the plug. After immersing the tip of the sample container in a swirled-up urine sample, the plunger is pulled out until the urine drawn in has reached a predetermined mark on the sample container with its liquid upper edge. The tip of the sample container is closed with the cap. In a next step, the plug must be from the top the piston. The piston is slowly and evenly fully inserted into the sample container. Afterwards, the sample container has to be inverted once with the piston inserted in order to pour off the excess urine, which is then discarded. The sample container is then reversed again. It is necessary to pull the plunger out of the sample container again until all of the urine is in the tip and the space above it. The flask is then completely pulled out of the sample container and discarded. Then the sample container is closed on the top with a stopper. The sample container is turned over and the interior is ventilated by removing the cap. After turning the sample container over again with the tip down, the tip is guided over the chamber into a slide. By exerting a slight short pressure approximately on the middle of the sealing plug, a sufficient amount of hammam is dispensed to fill a counting chamber. The above statements make it clear that the handling of the known device is extremely cumbersome, in particular due to the numerous handling steps.

The present invention is based on the object of designing and developing a generic device for enriching particles in body fluid in such a way that simple handling is possible without contaminating the operator with the body fluid. A simple construction of the device should keep the costs as low as possible.

The present invention solves the above object by the features of claim 1. Thereafter, the generic device for enriching particles in body fluid is designed and developed in such a way that in the flow path of the liquid flowing into and / or out of the receiving body, a fluid trapping the particles or receiving catcher is arranged.

According to the invention, it has been recognized that a commercially available syringe with the usual features can ultimately be used to implement a generic device, a special collecting device being used to enrich particles. This collecting device is in the flow path arranged in the receiving body and / or flowing out of the receiving body liquid.

In other words, a special collecting device for floating particles in the body fluid is provided here, so that the collecting device serves on the one hand to intercept and on the other hand to receive and store or store the floating particles or particles in the body liquid.

In the context of a first embodiment, the collecting device could be assigned to the inlet-side end of the receiving body, so that the collecting device is arranged between the piston used for suction and the suction / outlet opening which tapers like a pipette. The collecting device could also be assigned directly to the suction / outlet opening, namely it could be arranged within a component comprising the suction / outlet opening, so that a separation from the collecting device is ensured. In such a case, the collecting device could be easily removed from the receiving body.

In a further embodiment variant, the collecting device could be assigned to the piston surface, through openings being formed in the piston surface. In the context of such a configuration, the inside of the piston would be designed as a collecting container, the inflow of liquid into the collecting container being controllable by preferably manually opening and closing a ventilation valve formed at the end in the piston. It is essential that the body fluid is first sucked into the receiving body and, when the suction / outlet opening is closed, by pressing the piston in the direction opposite to the suction movement, it is pressed into the inside of the piston or into the collecting container. The body fluid passes through the collecting device, so that a thickening of the liquid takes place in the area of the collecting device, ie in the area of the piston surface. As already mentioned above, however, a reciprocal closing of the suction / outlet opening on the one hand and the ventilation valve formed at the end in the piston on the other hand is necessary, namely to first suck the liquid into the receiving body and then flow through the collecting device by introducing the liquid into the interior of the piston to enable. In concrete terms, the collecting device could be designed as a filter, with different filters for different fractions being able to be used depending on the particles or particles to be filtered out. The filter could be cellulose or a filter made of synthetic fibers or synthetic fabric. It is also conceivable to form the filter from an absorbent material with open porosity or passage porosity, so that passage of the liquid through the filter and sticking of the particles of interest in the filter is ensured. In any case, a "thickening" or an accumulation of the particles takes place within the filter.

The collecting device or the filter could be assigned to a filter insert and be removable from the filter insert. In the context of such a configuration, the interchangeability of the filter or the removability of the filter insert is ensured, so that it is also easily possible to remove the filter containing the trapped particles together with the filter insert and to carry them out for further analysis or processing.

The filter insert could be inserted into the inlet-side end of the receiving body and hold the collecting device there. It is also conceivable that the filter insert is an integral part of the inlet end of the receiving body.

Alternatively, the filter insert together with the filter could be attached to the piston surface. In a similar configuration, the filter insert could be an integral part of the piston surface.

In order to ensure a sufficient flow through the filter insert, which is ultimately necessary for trapping the particles in the filter or in the collecting device, it is of particular advantage if the filter insert comprises a liquid-permeable bottom and a wall suitable for holding the filter. The wall of the filter insert could encompass the filter as a whole and overlap, at least partially, at the edge area so that the filter is held securely in the filter insert. Ultimately, the filter of the through the Piston generated flow withstand the liquid and must not change its position.

In a very particularly advantageous manner, the filter insert is at least partially elastically deformable, and preferably compressible at least slightly in the axial direction. In the context of such a configuration, it is ensured that the filter and the filter insert can be virtually squeezed out, as a result of which the parts caught there are at least largely released for analysis or further processing.

The suction / outlet opening could be an integral part of the receiving body, in which case it would have the suction / outlet opening tapering like a pipette. In particular for easy opening or removal of the collecting device, it is of particular advantage to form the suction / outlet opening by a pipette tip that can be screwed onto the receiving body or a pipette tip that can be screwed into the receiving body. It is also conceivable that the suction outlet opening is formed by a pipette tip which can be plugged onto the receptacle body or inserted into the receptacle body. In both cases, the filter insert could be inserted into the pipette tip or into the corresponding component. In this respect, the collecting device or the filter can be removed by removing the filter insert, which ensures that the device can be handled particularly easily. It is also conceivable that the filter insert is an integral part of the pipette tip, so that the filter is only clamped or inserted into the filter insert integrated there.

A pluggable or screw-on closure is provided for closing the pipette tip. This closure is advantageously adapted essentially to the shape of the pipette tip, at least on the inside. In the context of a very particularly advantageous embodiment, the closure has essentially the same cross-section as the receiving body, so that when the pipette tip is closed, the device has a homogeneous appearance, which ensures particularly simple and safe handling, storage, stackability, etc. Finally, it should be noted that the individual components can be made entirely or at least predominantly of plastic, at least the receiving body being made of a transparent material. An observation of the sucked-in liquid but above all of the filter used there is guaranteed.

There are now various possibilities for advantageously designing and developing the teaching of the present invention. For this purpose, on the one hand, reference is made to the claims subordinate to claim 1, and on the other hand to the following explanation of exemplary embodiments of the invention with reference to the drawing. In connection with the explanation of the preferred exemplary embodiments of the invention with reference to the drawing, generally preferred refinements and developments of the teaching are also explained. Show in the drawing

1 shows a schematic side view, in section, of a first exemplary embodiment of a device according to the invention, the collecting device being assigned to the inlet-side end of the receiving body there,

2 shows a schematic side view, in section, of a second exemplary embodiment of a device according to the invention, the suction / outlet opening which tapers like a pipette being designed in the form of a screw-on pipette tip,

3 shows a schematic side view, in section, of a third exemplary embodiment, the collecting device being assigned to the piston surface there,

Fig. 4 in a schematic view, enlarged, a filter insert with an inserted filter, as it is used in the embodiments according to FIGS. 1 to 3 and 7

Fig. 5 in a schematic side view, sectioned and enlarged, a plug-on closure on the pipette tip.

FIGS. 1, 2 and 3 show mutually independent embodiments of a device according to the invention for the enrichment of particles in body fluid, this specifically being a device for providing an enriched suspension for analysis, namely for urinalysis. An examination of the "thickened" urine should thus be possible in the simplest possible way, in order to be able to diagnose inflammation or other diseases due to constituents in the urine. Normal centrifugation of the liquid is not necessary due to the thickening achieved.

The device comprises a cylindrical receptacle body 1 and a piston 2 which is displaceably arranged in the receptacle body 1 and is used for drawing in and expelling the liquid. The receptacle body 1 has a suction / outlet opening 3 which tapers like a pipette.

According to the invention, a collecting device 4 which catches or receives the particles is arranged in the flow path of the liquid flowing into and / or flowing out of the receiving body 1.

In the exemplary embodiments shown in FIGS. 1 and 2, the collecting device is assigned to the inlet-side end of the receiving body 1. In the exemplary embodiment shown in FIG. 2, the collecting device 1 is likewise assigned to the inlet-side end of the receiving body 1, the collecting device 4 being able to be assigned to the suction / outlet opening 3 or the component comprising the suction / outlet opening.

In the exemplary embodiment shown in FIG. 3, the collecting device 4 is assigned to the piston surface 5, the piston surface 5 including through openings 6. In the exemplary embodiment shown in FIG. 3, further sealing means 7 are provided in order to effectively prevent the liquid from escaping to the rear end of the receiving body 1. 8th

In the exemplary embodiment shown in FIG. 3, the interior of the piston is designed as a collecting container 8, in order to be able to receive the liquid through the collecting device 4 inside the piston 2.

Fig. 3 further shows that the inflow of liquid into the collecting container 8 by manual opening and closing of a ventilation valve 9 formed at the end in the piston 2 can be regulated, wherein this ventilation valve 9 can be revealed and closed by a stopper or by finger pressure.

In the exemplary embodiments shown in FIGS. 1, 2 and 3, the collecting device 4 is designed as a filter, the filter being a loose cellulose fabric. Synthetic material can also be used, whereby the formation of a predeterminable fraction must be ensured.

1, 2 and 3, but above all also FIG. 4, show particularly clearly that the collecting device 4 is assigned to a filter insert 10. The filter 11 can be removed from the filter insert 10. Furthermore, it is essential that the filter insert 10 can be installed in the receiving body 1 in different ways, namely as shown in FIGS. 1 and 2. This filter insert 10 is also suitable for placement on the piston 2, so that a direct assignment of the filter insert 10 to the piston 2 is ensured. In this regard, reference is made to the embodiment according to FIG. 3.

With regard to the functioning of the exemplary embodiment shown in FIG. 3, it should be noted that when the piston 2 is initially withdrawn, the through openings 6 formed in the piston 2 are closed by means of the covers 12 provided there. Because of this closure, the negative pressure required for suction is generated within the receiving body 1. If the piston 2 is then moved forward again towards the pipette tip, the front area of the piston 2 detaches from the cover 12, so that the liquid in the receiving body 1 through the through openings 6 into the inside of the piston or into the collecting container 8 inside the Piston 2 can flow. The filtering process takes place. 4, the filter insert 10 comprises a liquid-permeable bottom area 13 and a wall 14 suitable for holding the filter 11. This wall 14 surrounds the filter 11 as a whole and partially overlaps the filter 11, so that a locking or holding the Filters 11 is guaranteed within the filter insert 10.

In the exemplary embodiment shown in FIG. 1, the pipette tip 15 is an integral part of the receiving body 1.

In the exemplary embodiment shown in FIG. 2, the pipette tip 15 is an independent component, which is screwed onto the receiving body 1 from the outside. This is only indicated in Fig. 2.

The same applies to the exemplary embodiment shown in FIG. 3, in which the pipette tip 15 is screwed onto the receiving body 1.

A pluggable closure 16, which is shown in isolation in FIG. 5, is provided for closing the pipette tip 15. The interior of this closure 16 corresponds essentially to the shape of the pipette tip 15 or is adapted to the pipette tip 15. By plugging on the closure 16, the device can be securely closed before and / or after use.

The device discussed above with reference to three exemplary embodiments can be used to find erythrocytes and leukocytes in the urine, namely to compress these components (cells) in the urine. For this purpose, the liquid - or, in the example discussed here, the urine - is drawn out of a sample container not shown in the figures into the receiving body 1, and in the case of the exemplary embodiments shown in FIGS. 1 and 2 by the collecting device 4 or the Filter 11 pulled through.

In the exemplary embodiment shown in FIG. 3, the passage through the collecting device 4 or the filter 11 only takes place when the liquid is ejected or when the liquid penetrates into the interior of the piston or into the collecting container 8. In any case, the cells in the urine settle on or in the filter 11. By rinsing the filter 11 again, the cells are virtually flushed back and can 10

NEN drop by drop from the suction / outlet 3, for example. On a slide or in a cell chamber. In any case, simple means achieve a thickening of the particles in the body fluid, which can then be subjected to an examination.

Finally, it should be particularly emphasized that the exemplary embodiments discussed here serve to explain the claimed teaching, but do not restrict it to the exemplary embodiments.

Claims

11 patent claims

1. Device for enriching particles in body fluid, in particular for providing an enriched suspension for analysis, with a preferably cylindrical receiving body (1) and a piston (2) slidably arranged in the receiving body (1) and used to draw in and expel the liquid. wherein the receiving body (1) has a pipette-like tapering suction / outlet opening (3), characterized in that in the flow path of the liquid flowing into the receiving body (1) and / or flowing out of the receiving body (1), a particle trapping or receiving Collection device (4) is arranged.

2. Apparatus according to claim 1, characterized in that the collecting device (4) is assigned to the inlet-side end of the receiving body (1).

3. Apparatus according to claim 1, characterized in that the collecting device (4) is assigned directly to the suction / outlet opening (3).

4. The device according to claim 1, characterized in that the collecting device (4) is associated with the piston surface (5), through openings (6) being formed in the piston surface (5).

5. The device according to claim 4, characterized in that the piston interior is designed as a collecting container (8).

6. The device according to claim 5, characterized in that the inflow of liquid into the collecting container (8) by preferably manually opening and closing an end in the piston (2) formed ventilation valve (9) is controllable.

7. Device according to one of claims 1 to 6, characterized in that the collecting device (4) is designed as a filter (11). 12

8. The device according to claim 7, characterized in that the filter (11) is made of cellulose or synthetic fibers or synthetic fabric.

9. The device according to claim 7, characterized in that the filter (11) is made of an absorbent material with open porosity or through porosity.

10. Device according to one of claims 1 to 9, characterized in that the collecting device (4) is assigned to a filter insert (10) and can be removed from the filter insert (10).

11. The device according to claim 10, characterized in that the filter insert (10) is inserted into the inlet-side end of the receiving body (1).

12. The apparatus according to claim 10, characterized in that the filter insert (10) is an integral part of the inlet end of the receiving body (1).

13. The apparatus according to claim 10, characterized in that the filter insert (10) is attached to the piston surface (5).

14. The apparatus according to claim 10, characterized in that the filter insert (10) is an integral part of the piston surface (5)

15. Device according to one of claims 1 to 14, characterized in that the filter insert (10) comprises a liquid-permeable bottom (13) and a wall (14) suitable for holding the filter (11).

16. The apparatus according to claim 15, characterized in that the wall (14) surrounds the filter (11) as a whole and, at least partially, engages over at the edge region. 13

17. Device according to one of claims 10 to 16, characterized in that the filter insert (10) is at least partially elastically deformable, preferably at least slightly compressible in the axial direction.

18. Device according to one of claims 1 to 17, characterized in that the suction / outlet opening (3) is an integral part of the receiving body (1).

19. Device according to one of claims 1 to 17, characterized in that the suction / outlet opening (3) is formed by a pipette tip (15) which can be screwed onto the receiving body (1) or screwed into the receiving body (1).

20. Device according to one of claims 1 to 17, characterized in that the suction / outlet opening (3) is formed by a pipette tip (15) which can be plugged onto the receiving body (1) or inserted into the receiving body (1).

21. The apparatus according to claim 19 or 20, characterized in that the filter insert (10) is inserted into the pipette tip (15).

22. The apparatus according to claim 19 or 20, characterized in that the filter insert (10) is an integral part of the pipette tip (15).

23. Device according to one of claims 19 to 22, characterized in that a pluggable or screw-on closure (16) is provided for closing the pipette tip (15).

24. The device according to claim 23, characterized in that the closure (16) is adapted at least in the interior substantially to the shape of the pipette tip (15).

25. Device according to one of claims 1 to 24, characterized in that the individual components are made entirely or at least predominantly of plastic.