WO2005068967A1

WO2005068967A1 - A device for investigating biological test fluids, especially blood, urine or the like

Info

Publication number: WO2005068967A1
Application number: PCT/EP2004/014551
Authority: WO
Inventors: Herbert Argauer
Original assignee: Wilden Ag
Priority date: 2004-01-15
Filing date: 2004-12-21
Publication date: 2005-07-28
Also published as: DE202004000567U1

Abstract

A device for investigating biological test fluids, especially blood, urine or the like, comprises a sample application portion (6), a measuring chamber (2), and an axial slide valve element (8) which includes a dosing capillary (10). The axial slide valve element (8) can be moved from a first position in which the sample application portion (6) is in fluid communication with the dosing capillary (10), to a second position in which the dosing capillary (10) is in fluid communication with the measuring chamber (2). Checking means are provided for checking a filling of the dosing capillary (10) with test fluid in the first position of the axial slide valve element (8) and/or an emptying of the dosing capillary (10) into the measuring chamber (2) in the second position of the axial slide valve element (8). The checking means comprise a checking chamber (13) adapted to be filled with the test fluid. The checking chamber is in fluid communication with one of the end portions of the dosing capillary (10) at least in the first position of the axial slide valve element (8), and is visible through a checking opening (7) in the first position of the axial slide valve element (8).

Description

A DEVICE FOR INVESTIGATING BIOLOGICAL TEST FLUIDS, ESPECIALLY BLOOD, URINE OR THE LIKE

FIELD AND BACKGROUND OF THE INVENTION

The invention relates to a device for investigating biological test fluids, especially blood, urine or the like.

A device of the present type is known from EP 1 240 944 A2 and comprises a dosing element in the form of a rotary part which is seated in a rotor housing for rotation about an axis. A dosing capillary having two openings is integral part of the rotary part. The rotary part can be rotated between two positions which differ in regard to the orientation of the dosing capillary. In a first position, the dosing capillary is connected to a sample collecting zone so that a blood sample present therein can enter the dosing capillary for filling it. Since complete filling of the dosing capillary is of importance for the accuracy of the analysis, a monitoring capillary incorporating an electronic fill- checking device in the form of a light barrier is provided in the rotary housing at a position whereat the rotary part is located when the capillary is full. A device of the present type is further known from DE 35 07 032 C2, wherein a dosing capillary is integrated into a moveable supplying slide valve which, in two different embodiments thereof, is either displaceable in a direction transverse to the longitudinal direction of a dosing capillary or is mounted in appropriate fit seat for rotation between different rotational positions. The known devices are of complicated construction and are correspondingly expensive which thus undermines their intended purpose of being disposable products, and, moreover, there is a need of an improvement as regards the handling thereof. OBJECTS OF THE INVENTION

An object of the present invention is to provide a device of the present type which is of simplified construction and can be manufactured in economical manner with less costs. A more specific object of the present invention is to provide a device of the present type by which a high accuracy of analysis can be ensured whilst at the same time the device should be adapted to be handled in quick and safe manner. Still another object of the present invention is to provide a device of the present type in the form of a throw-away product for single use.

SUMMARY OF THE INVENTION

In accordance with the present invention these and other objects are obtained by a device for investigating biological test fluids, especially blood, urine or the like, which comprises: a sample application portion; a measuring chamber, and an axial slide valve element having a dosing capillary, said axial slide valve element can be moved or displaced from a first position in which the sample application portion is in fluid communication with the dosing capillary to a second position in which the dosing capillary is in fluid communication with the measuring chamber.

There is further provided a checking means for visually checking or monitoring a filling of the dosing capillary with the test fluid in the first position of the axial slide valve element and/or an emptying of the dosing capillary into the measuring chamber in the second position of the axial slide valve element. On the one hand, this ensures that the dosing capillary is properly filled as a requirement for obtaining reliable test results whilst, on the other hand, it can be checked as to whether the test fluid has been transferred from the dosing capillary to the test strips so to enable an accurate analysis of the sample.

In one advantageous embodiment of the invention, the checking means comprises a checking chamber which is adapted to be filled with the test fluid and is in fluid communication with one of the end portions of the dosing capillary at least in the first position of the axial slide valve element. The checking chamber is visible through a checking opening at least when the axial slide valve element is in the first position thereof. This enables information to be obtained in regard to the degree to which the dosing capillary is filled.

According to one advantageous embodiment of the invention in order to provide a fluid communication between the checking chamber and the dosing capillary in simple manner, a connecting channel between one of the end portions of the dosing capillary and the checking chamber is provided in the axial slide valve element. According to a further embodiment of the invention, an end portion of the dosing capillary facing the sample application portion may be permanently connected to the checking chamber through the connecting channel. This permits a person to determine whether or not filling of the dosing capillary is taking place. In an alternative embodiment of the invention, the end portion of the dosing capillary can be remote from the sample application portion and can be connected to the checking chamber by the connecting channel in the first position of the axial slide valve element only. This enables a person to determine whether or not complete filling of the dosing capillary has taken place.

The checking opening can be aligned with the dosing capillary in the second position of the axial slide valve element so that the dosing capillary can be ventilated through the checking opening for the purpose of equalising pressure in the second position. Thereby proper supply of the sample fluid from the dosing capillary is ensured while this can be monitored. The axial slide valve element advantageously is formed as a piston assembly. This substantially facilitates the handling of the device according to the invention by one hand.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are shown in the drawings, wherein:

Fig. 1 is a perspective, partly cut-away view of a first embodiment of a device according to the invention,

Fig. 2 is an enlarged detailed view of the device similar to Fig. 1 with the axial slide valve element in a secured status,

Fig. 3 is a view of the device similar to Fig. 2 with the axial slide valve element i a pushed inward status,

Fig. 4 is a longitudinal sectional view of the device with the axial slide valve element in a pushed inward status ,

Fig. 5 is a longitudinal sectional view of the device with the axial slide valve element in a secured status,

Fig. 6 is a perspective view of a second embodiment of a device according to the invention,

Fig. 7 is a perspective exploded view of the device shown in Fig. 6,

Fig, 8 is a perspective, longitudinal sectional view of the" device shown in Fig. 6 with the axial slide valve element in a secured status, Fig. 9 is a perspective enlarged detailed view similar to Fig. 8 with the axial slide valve element in a secured status, and

Fig. 10 is a detailed view similar to Fig. 9 with the axial slide valve element in a pushed inwards status.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

Further advantages, details and features of the present invention will become apparent from the following detailed description of the preferred embodiments of the invention in conjunction with the accompanying drawings.

A first embodiment of the invention will be described hereinafter with reference to Figs. 1 to 5. The device in accordance with this embodiment comprises a preferably essentially flat, preferably rectangular base body 1 which may be composed of a bottom part 1a and a cover part 1 b between which a measuring chamber 2 is formed. An elongated test strip 3 (c.f. Fig. 4 or 5) made of an absorbent material such as paper conditioned for the purpose of a particular investigation can be disposed in the measuring chamber 2. Test strips of this type are known to the skilled person and consequently do not need more detailed explanation.

A pair of axially spaced read-out windows 4 through which the test strip in the measuring chamber 3 is visible for reading off the result of the analysis as manifested by the test strip 3 is provided in the cover part 1 b in the axial direction or the direction in which the test strip 3 extends. While two read-out windows 4 are provided in the illustrated embodiment, one or more read-out windows 4 could be provided, if desired.

A tubular shoulder part 5 provided with a tub-shaped sample collecting or application portion 6 is formed on the top side of the base body 1 near one of the axial ends thereof. An checking opening 7 is provided in the tubular part 5 at an axial distance from the sample application portion 6. The checking opening 7 is aligned with an adjacent end portion of the test strip 3.

The sample application portion 6, the checking opening 7 and the read-out windows 4 in the cover part 1 b face upwardly in the operative position of the device.

Furthermore, an axial slide valve element 8 in the form of a piston assembly is accommodated in axially moveable manner in the tubular part 5, said element can be moved or pushed into the tubular part 5 by a suitable distance. A breakable security element 9 is provided on the axial slide valve element 8 for preventing movement of the axial slide valve element 8 into the tubular part 5 for as long as said security element is in an intact state.

At an intermediary location thereof, the axial slide valve element 8 contains a dosing capillary 10 which is open at both ends and extends radially or transversely relative to the direction of movement of the axial slide valve element 8. The dosing capillary 10 runs perpendicularly from top to bottom in the operative position of the device. In the secured position of the axial slide valve element 8, the one or upper open end of the dosing capillary 10 is connected to an outlet opening 11 of the sample application portion 6 so that a test fluid applied to the sample application portion 6c an enter the dosing capillary 10 and can be drawn into said dosing capillary by capillary action.

Furthermore, a connecting channel 12 branches off the dosing capillary 10 near the upper open end thereof, c.f. Figs. 4 and 5, and extends on the upper surface of the axial slide valve element 8 in the direction of the base body 1. The connecting channel 12 opens into a recess or checking chamber 13 which can be observed from above through the checking opening 7 and is formed on the axial slide valve element 8. The length of the connecting channel 12 essentially corresponds to the distance between the outlet opening 11 of the sample application portion 6 and the checking opening 7.

The axial displacement path of the axial slide valve element 8 is such that it corresponds to the distance between the outlet opening 11 of the sample application portion 6 and the checking opening 7. In the secured state of the axial slide valve element 8 (c.f. Figs. 2 and 5), the dosing capillary 10 is aligned with the outlet opening 11 of the sample application portion 6, whereas in the pushed-in state of the axial slide valve element 8 (c.f. Figs. 3 and 4), the dosing capillary 10 is aligned with the checking opening 7. Consequently, in the pushed-in position of the axial slide valve element 8, the dosing capillary 10 can be ventilated through the checking opening 7, this thereby enabling pressure to be equalised so that the sample fluid can emerge more easily from the lower end of the dosing capillary 10 and be absorbed by the test strip 3. Moreover, this procedure can be monitored through the checking opening 7.

Furthermore, in the secured state of the axial slide valve element 8 and as a consequence of the permanent connection of the dosing capillary 10 to the checking chamber 13 through the connecting channel 12, the checking opening 7 enables one to establish whether or not the test fluid from the sample application portion 6 has entered the dosing capillary 10.

In Fig. 2, the device is shown in a state wherein the axial slide valve element 8 is secured and a sample can be applied onto the sample application portion 6. The sample can enter the dosing capillary 10 through the outlet opening 11. Part of the sample flows out of the dosing capillary 10 into the connecting channel 12 and from there into the checking chamber 13 so that one can realise through the checking opening 7 as to whether the dosing capillary 10 is filled. If the security element 9 is broken off and the axial slide valve element 6 is pushed into the tubular part 5 up to the stop (c.f. Fig, 3), the upper end of the dosing capillary 10 becomes aligned with the checking opening 7 and the other or lower end thereof is aligned with the test strip 3. The test strip 3 can now receive the sample. The test result can then be read off through the two read-out windows 4.

A second embodiment of the invention is shown in Figs. 6 to 10.

This embodiment distinguishes from the first embodiment shown in Figs. 1 to 5, essentially by a different design of the checking means for detecting whether or not the dosing capillary is filled correctly. Parts which are same as or similar to those of the first embodiment bear the same reference numbers but increased by a factor of 100 and do not require another detailed description.

In the second embodiment, the tubular part 105 preferably comprises a tubular inner part 115 which facilitates the assembly of the device and can be accommodated or pushed into the tubular part 105. The dosing capillary 110 is provided near the end of the axial slide valve element 108 facing towards the base body 100. The one or upper end of the dosing capillary 110 is connected to the sample application portion 106 when the axial slide valve element 108 is in the secured position, i.e. it has not been pushed into the tubular part 105 or the inner part 115 (c.f. Fig. 8).

A checking opening 107 is provided in the tubular part 105 and is aligned with a checking chamber 113 in the inner part 115. Accordingly the checking opening 107 and the checking chamber 113 are stationary. The checking chamber 113 can be connected to the dosing capillary 110 through a connecting channel 120 comprising stationary and moveable sections 120a, 120b when the axial slide valve element 108 is in the secured position (c.f. Fig. 9). The first or stationary section 120a of the connecting channel 120 is formed in the wall of the tubular inner part 115 and extends therein in the direction of displacement of the axial slide valve element 108. The second or moveable section 120b of the connecting channel 120 is formed in the axial slide valve element 108 and may extend in parallel with the dosing capillary 110. In the secured position of the axial slide valve element 108, the lower end of the dosing capillary 110 remote from the sample application portion 106 is connected to the adjacent end of the first section 120a whilst the other end of the first section 120a is aligned with the adjacent end of the second section 120b formed in the axial slide valve element 108 so that a fluid communication is thereby produced. The other or upper end of the second section 120b is connected to the checking chamber 113 so that, in the secured state (c.f. Fig. 9), the checking chamber 113 receives the sample through the connecting channel 120 whereby complete filling of the dosing capillary 110 can be monitored through the checking opening 114.

Fig. 10 shows the state which the axial slide valve element 108 adopts for carrying out an analysis when the axial slide valve element 108 has been pushed-in further. In this position, the lower end of the dosing capillary 110 makes contact with the test strip 103 and the sample can be transferred thereto so that an analysis can be carried out. The moveable section 120b of the connecting channel 120 is no longer connected to the stationary section 120a of the connecting channel 120 in these circumstances.

The second embodiment of the invention has the advantage that the complete filling of the dosing capillary 110 with the sample in the secured position of the axial slide valve element 108 can be determined more reliably than with the first embodiment since the withdrawal of the test fluid is monitored at the end of the dosing capillary 110 remote from the sample application portion 106 whereby a display is given in the checking chamber 113 when the dosing capillary 110 is completely filled. If desired, a further checking opening similar to the checking opening 107 can be provided at a position of the tubular part 105 which corresponds to the position of the dosing capillary 110 in the pushed-in position of the axial slide valve element 108 in order to enable the process of emptying the dosing capillary 110 to be monitored and the pressure equalising process to be improved.

The above description of embodiments of the invention has been given by way of example. From the disclosure given, those skilled in the art will not only understand the present invention and the attendant advantages, but will also find apparent various changes and modifications to the structures disclosed. It is sought, therefore, to cover all such changes and modifications as within the spirit and scope of the invention, as defined by the appended claims, and equivalents thereof.

Claims

What is claimed is:

1. A device for investigating biological test fluids, especially blood, urine or the like, comprising: a sample application portion (6, 106), a measuring chamber (2, 102), and an axial slide valve element (8, 108) including a dosing capillary (10, 110), said axial slide valve element (8, 108) being movable from a first position in which the sample application portion (6, 106) is in fluid communication with the dosing capillary (10, 110), to a second position in which the dosing capillary (10, 110) is in fluid communication with the measuring chamber (2, 102).

2. The device according to claim 1 , and having checking means for checking filling of the dosing capillary (10, 110) with the test fluid in the first position of the axial slide valve element (8, 108) and/or emptying of the dosing capillary (10, 110) into the measuring chamber (2, 102) in the second position of the axial slide valve element (8, 108).

3. The device according to claim 2, wherein said checking means comprises a checking opening (7, 107) provided in a base body (1 , 100) of the device.

4. The device according to claim 3, wherein said checking means comprises a checking chamber (13, 113) adapted to be filled with the test fluid, said checking chamber is in fluid communication with one of the end portions of the dosing capillary (10, 110) at least in the first position of the axial slide valve element (8, 108), while being visible through the checking opening (7, 107) at least in the first position of the axial slide valve element (8, 108).

5. The device according to claim 4, and a having a connecting channel (12, 120) between one of the end portions of the dosing capillary (10, 110) and the checking chamber (13, 113).

6. The device according to claims 4, wherein said one end portion of the dosing capillary (10) faces the sample application portion (6) and is permanently connected to the checking chamber (13) by the connecting channel (12).

7. The device according to claims 4, wherein said one end portion of the dosing capillary (110) is remote from the sample application portion (106) and is connected to the checking chamber (113) by the connecting channel (120) in the first position of the axial slide valve element (108) only.

8. The device according to claim 3, wherein said checking opening (7) is aligned with the dosing capillary (10, 110) in the second position of the axial slide valve element (8, 108) for ventilating the dosing capillary (10,110) for equalising pressure.

9. The device according to claim 1 , wherein the axial slide valve element (8, 108) is in the form of a piston assembly.

10. The device according to claim 1 , and having a security element (9, 109) for locking the axial slide valve element (8, 108) in the first position thereof in releasable manner.

11. The device according to claim 10, wherein the security element (9, 109) is breakable for releasing the axial slide valve element (8, 108).

12. The device according claim 1 , and having at least a single read-out window (4, 104) aligned with the measuring chamber (2, 102) for reading a test strip (3, 103) arranged in the measuring chamber (2, 102).