Abstract:
This invention relates to a device for collecting and releasing saliva. The purpose of the invention is to provide sample device which is easy and safe to handle and which is configured as a disposable construction for use especially on medical diagnostics. To this end, the device consists of a porous unit which can take up the sample fluid and can be squeezed out. The unit is located inside a container which is sealed on one side at one end, and is arranged in such a way that it can be displaced out of said container at the other end which can be opened. The end of the container which can be opened is provided with a sealing cap.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a device for collecting and releasing saliva for diagnostic purposes. 
     In the prior art, there are devices and methods, respectively, known in the field of art. So in DE 36 32 303 A1 a chewable, absorbent, elastic, and inert profiled body is placed in the mouth of a proband until said body is penetrated with saliva. Then the body is placed in a centrifuge tube which, at its bottom, is provided with openings through which the saliva escapes in the course of centrifugation so that it is available for further examinations. In EP 0 520 408 A1 there is described a sample device for collecting saliva and other fluid exudations that comprises a sample receptacle with an indicator and a reaction fluid. A special embodiment of the sample receptacle described there is provided with a body made of a porous mass which is adapted to collect the sample fluid and the reagent fluid and which can be squeezed out by a plunger. Due to the fact that the desired chemical reaction or the application of a buffer solution for the saliva sample is carried out within the entire device, in which simultaneously a sample analysis has to be performed, the device design is comparatively expensive so that it is too cost-intensive for a one-off use only. Similar devices have been described in, for example, U.S. Pat. No. 5,268,148, WO 95/02996, and WO 94/04078. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a device for collecting and releasing saliva that permits a simple and safe handling and is designed as a disposable unit, in particular for diagnostic purposes, whereby the risk of contamination both of the sample to be collected and for the personnel handling the device is substantially obviated. 
     The object is realized by the features of the first claim. Advantageous embodiments are covered by the dependent claims. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention will be described hereinafter in more detail by reference to the schematical embodiments. There is shown in: 
     FIG. 1 a lateral section of a first embodiment in an initial position before use, 
     FIG. 2 the embodiment of FIG. 1 in service position for receiving saliva or any other sample fluid, 
     FIG. 3 a lateral partial section of a modified embodiment of FIG. 1 in a service position, 
     FIG. 4 a lateral section of a second embodiment in both, an initial position and in a service position, 
     FIG. 5 an end position according to FIG. 4 in which the collected saliva or the sample fluid is released, 
     FIG. 6 a perspective view of a third embodiment in a service position, 
     FIG. 6 a  a locking cap for an embodiment according to FIG. 6, 
     FIG. 7 a view, partially perspective, of a fourth embodiment in a service position, and 
     FIG. 8 a special embodiment of the locking cap. 
    
    
     FIG. 1 shows a first embodiment of a device for collecting and releasing saliva or other sample fluids. The device comprises a porous unit  1  adapted to be squeezed out that consists of polyurethane, water-catalyzed polyurethane, polyethylene, polypropylene or cellulose. Said porous unit  1  is displaceably arranged in a receptacle, in the present example in a bellow  20 . The bellow  20  is provided with a closed end-portion  21  and an end-portion  22  that can be opened. A locking cap  3  is adapted for fitting on said end-portion  22 . The interior wall of the porous unit  1  is provided with a supporting means which, in the present example, is embodied by a drainage tube  41 . Openings  42  are circumferentially distributed over a part of said drainage tube  41 . Furthermore, the porous unit in the present example is externally enclosed by a hose-like foil  5 . The locking cap  3  used herein comprises a conic mouthpiece  32 , the interior wall of which is provided with capillary grooves  33 . The device is put into a service position by removing the locking cap  3  which is connected to the bellow  20  in that the bellow  20  is seized at a flanged handle  6  by two fingers of one hand while the thumb presses upon the closed end-portion  21  of the bellow. Thereby the porous unit  1  and the drainage tube  41  supporting the former is slidingly moved out of the bellow  20 , whereas the hose-like foil  5  is slidingly pushed together in the interior of the bellow  20  by the action of respective counteractive means or by being bonded to the base ranges of the bellow. The service position described is shown in FIG.  2 . The porous unit  1  is then placed in a not shown mouth of a proband and takes up there a quantum of saliva necessary for further tests. Additionally the porous unit  1  can be impregnated with a substance for stimulating salivation and/or with a test agent for indicating, for example, drugs. In order to define a preselected insertion depth, the bellow  20  and the receptacles represented in the following embodiments, respectively, can additionally be provided with an oral stop plate  9 . 
     Furthermore, the bellow  20  can be provided with means  7 ,  7 ′ that, in the compressed state of the bellow, are interlocked. When sufficient saliva has been taken up, the locking mechanism  7 ,  7 ′ is released and when there is employed an elastic one for the bellow  20 , the porous unit  1  and the drainage tube  41  are retracted into the bellow  20  provided that the drainage tube  41  is brought into a rigid connection with the interior wall  201  of the bellow in the range of the closed end-portion  21  of the bellow. Preferably said rigid connection  24  circumferentially seals the interior wall  201  of the bellow so that two chambers  202  and  203  result to which different pressure can be applied. When the rigid connection  24 , as represented in FIG. 3, is somewhat moved off from the closed end-portion  21  of the bellow, the volume of the chamber  203  is increased in such a manner that when only relieving this part of the bellow an underpressure is produced, as indicated by the arrows in FIG. 3, whereby the porous unit  1  is still better humidified by saliva throughout. 
     In FIG. 4 a second embodiment is represented with substantial features of FIG. 1 in common. Here, however, in contrast to FIG. 1, the bellow  20  is inelastically embodied, the drainage tube  41  is not rigidly connected to interior wall  201  of the bellow and the porous unit  1  is not enclosed by a hose-like foil  5 . Herein the drainage tube  41  is only provided with a stop  43  at the interior side of the bellow. In this example, after removal of the locking cap, not shown in FIG. 4, the porous unit  1  together with the supporting drainage tube  41  is only shaken out of the bellow  20  by force of gravity and brought into the position of service, shown in dash-lines. The dimensions of the stop are such that the latter remains within the bellow  20  even in the position of service. In the following, the procedure is in analogy to FIG.  1 . After sufficient saliva has been taken up the porous unit  1  with the drainage tube  41  supporting the former is moved back again into the bellow. Then the locking cap  3  is put on. The device, which now contains a sample fluid (saliva), can now be fed into an analysis device, not shown in detail. To this end and in the same manner pressure is applied to the devices according to FIG.  1  and FIG. 2, as indicated by an arrow in FIG.  5 . For this purpose the locking cap  3  is provided with an open aperture  31  or with an aperture which will now be opened. The feasibility of closing the aperture  31  is given to the end that the sample fluid in the receptacle is additionally provided with a buffer solution or has already been provided with a reagent and has to be transported or stored. In each case, however, the geometry of the aperture  31  is so designed that it corresponds to the cross-section of the supporting means, which is here the drainage tube  41 , and only permits the passing through of the latter when pressure is applied whereas the porous material remains in the bellow  20  where it is compressed whereby the sample fluid is passed into the analysis device via the protruding drainage tube  41 . Advantageously, the drainage tube as described in the embodiment up to here can be provided on its interior wall, with respect to the molecular weight of the sample fluid, with a selective filter  8 . 
     FIG. 6 shows a simplified embodiment, which lies within the scope of the invention, that comprises a receptacle  2  with a closed end portion  21 , respectively with an end portion  21  adapted to be tightly sealed. The receptacle  2  has a sleeve, not shown in detail, slidingly engaged within said receptacle  2 . Said sleeve is adapted to receive a porous unit  1  that is, according to FIG. 6, of oval-shaped cross-section. A supporting means  4  is inserted into the unit  1  and a supporting means  4 ′, respectively, is worked into the upper circumference of the unit  1 . A locking cap  3 , separately shown in FIG. 6 a , is connected via a connecting tongue  34  to the unlockable end-portion  22  of the receptacle  2 . In the case of the supporting means  4  being centrally inserted and rigidly connected to a slider  11 , the locking cap  3  is also provided with an aperture  31 , the geometry of the same is adapted to the cross-section of the supporting means  4 . It is, however, also feasible to design the embodiment in such a manner that, for example, a circular aperture  31  is provided wherein the opening of the same is not adapted to the cross-section of the supporting means  4 . Then the supporting means  4  is not able to pass through the aperture  31  when the slider  11  is slidingly advanced and the porous unit  1  is compressed. In this case a suitable passage facility for the supporting means  4  has to be provided at the bottom of the not shown sleeve, thus ensuring that said supporting means remains in the receptacle  2  while the porous unit  1  is compressed. At such an embodiment a selective filter  8  can be fitted into the locking cap  3 . Also in this embodiment the locking cap  3  can be designed conically and in analogy to that represented in FIG.  1 . The handling of the present embodiment is in analogy to that described in connection with FIGS. 1 to  5 . 
     FIG. 7 shows a perspective partial view of a further embodiment that largely corresponds to that described in FIG. 6, apart from the fact that here the porous unit  1  is of circular cross-section and the further components are adapted to this geometry. In FIG. 7 the sleeve  12 , not shown in more detail in FIG. 6, is overdrawn in an enlarged view. 
     Furthermore, with all the embodiments described, in which at least the closed end portion  21  of the receptacle is designed optically transparent, the invention suggests within its scope to impregnate with a test agent and/or with an indicator at least that portion of the porous unit  1 , which lies within the range of the closed end portion of the receptacle. As a result thereof and, for example, due to color change, it is feasible to optically indicate a sufficient amount of sample fluid required. 
     In all those cases in which the porous unit  1  is not provided with a supporting means, the locking cap  3  can be further designed in an embodiment as it is indicated by example of FIG.  8 . Said embodiment is designed in such a way that the locking cap  3  is provided, on the one hand, with a filter  35  that permits passage of the sample fluid with the locking cap put on and when the porous unit is compressed and, on the other hand, with a filter  36  permeable to gas that prevents the passage of the sample fluid. Thereby the locking cap itself is adapted to be filled with a sample fluid, it can be removed after cutting through the connecting tongue  34 , closed by a cover  37 , and stored separately. In this case, it lies within the scope of the invention to impregnate the filter  35  with a substance that, for example, preserves the saliva sample (for example, a biocide such as sodium azide), the pH-value of which buffers off, the surface tension of which reduces and complexes metal ions in the saliva sample. It lies within the frame of such a design to provide any further test agents within the locking cap. Furthermore, the outer shape of the locking cap  3  can be so designed that it can be directly inserted into a conventional analysis device. 
     All the embodiments represented are, due to their setup, disposable devices, in particular, for a rapid medical diagnosis by which, however, their application is not restricted. In the same way they can be used in receiving and releasing any desired sample fluids. 
     All features disclosed in the specification, in the subsequent claims, and in the drawing are substantial for the invention both, individually and in any combination with one another. 
     List of Reference Numerals 
       1  porous unit 
       2  receptacle 
       20  bellow 
       201  interior wall of bellow 
       202 ,  203  chambers under different pressure 
       21  closed end-portion of receptacle 
       22  unlockable end-portion of receptacle 
       24  rigid connection 
       3  locking cap 
       31  aperture 
       32  conic mouthpiece 
       33  capillary grooves 
       34  connecting tongue 
       35  filter for sample fluid 
       36  filter permeable to gas 
       37  cover 
       4  supporting means 
       41  drainage tube 
       42  openings 
       43  stop 
       5  hose-like foil 
       6  flanged handle 
       7 ,  7 ′ locking means 
       8  selective filter 
       9  oral stop-plate 
       11  slider 
       12  sleeve