CA2677407C

CA2677407C - Analysis system for determining an analyte in a body fluid and disposable integrated sample acquisition and analysis element

Info

Publication number: CA2677407C
Application number: CA2677407A
Authority: CA
Inventors: Hans List; Volker Zimmer; Michael Keil
Original assignee: F Hoffmann La Roche AG
Current assignee: F Hoffmann La Roche AG
Priority date: 2007-03-14
Filing date: 2008-03-05
Publication date: 2012-05-15
Anticipated expiration: 2028-03-05
Also published as: EP1970006A1; KR20090110376A; CN101631500A; WO2008110287A2; KR101175967B1; US8114028B2; CA2677407A1; MX2009009120A; HK1140400A1; WO2008110287A3; JP2010520793A; EP2129289A2; CN101631500B; JP5465014B2; US20100036282A1; EP2129289B1

Abstract

Analysis system for determining an analyte in a body fluid, comprising - a disposable integrated sample acquisition and analysis element, which comprises a piercing element (7) having a tip (15) for generating a puncture wound in a body part and a flat test strip (6) having a sample receiving zone (10), into which a body fluid sample is transferred to perform an analysis, and - a reusable analysis instrument (2), comprising a coupling unit, which is adapted to couple an integrated sample acquisition and analysis element to a drive, by which a piercing movement of the piercing element (7) is driven, the piercing movement comprising a propulsion phase in which the piercing element (7) is moved on a puncture path in the puncture direction and a retraction phase in which the piercing element (7) is moved opposite to the puncture direction after reaching a reversal point of the piercing movement and further comprising a measuring and analysis unit (36) for measuring a measurement variable characteristic for the determination of the analyte and for determining a desired analysis result on the basis of the measurement.

The sample receiving zone (10) of the test strip (6) is located on one of its flat sides (9), which forms a sample contact side (11). The piercing element (7) is located parallel to the test strip (6) and is movable on the movement path relative to the test strip (6) during at least a part of the puncture movement. The piercing element (7) is located adjacent to the sample contact side (11) of the test strip (6). It has a capillary channel (17), which has a sample inlet (23), through which the body fluid may enter into the capillary channel (17) after the piercing, and a sample outlet (24), through which the body fluid may exit from the capillary channel (17). The movement path of the piercing element (7) comprises a sample transfer position, in which the sample outlet (24) is adjacent to the sample receiving zone (10) of the test strip (6) in such a manner that the body fluid may be transferred from the capillary channel (17) through the sample outlet (24) to the sample receiving zone (10).

Description

Applicant: F. HOFFMANN-LA ROCHE AG

Analysis system for determining an analyte in a body fluid and disposable integrated sample acquisition and analysis element The present invention relates to an analysis system for determining an analyte in a body fluid having a disposable integrated sample acquisition and analysis element and having a reusable analysis instrument. The disposable sample acquisition and analysis element comprises a piercing element having a tip for generating a puncture wound in a body part and a flat test strip having a sample receiving zone for receiving a body fluid sample exiting from the puncture wound. The analysis instrument comprises a coupling unit for coupling a sample acquisition and analysis element to a drive, by which a puncture movement of the piercing element is driven. The piercing movement comprises a propulsion phase in which the piercing element is moved on a puncture path in the puncture direction and a retraction phase in which the piercing element is moved opposite to the puncture direction after reaching the reversal point of the puncture movement. The analysis instrument also comprises a measuring and analysis unit for measuring a measurement variable which is characteristic for the determination of the analyte and for determining a desired analysis results based on the measurement. The sample receiving zone of the test strip is located on one of its flat sides, which forms a sample contact side. The piercing element is located parallel to the test strip and is movable relative to the test strip on a movement path during at least a part of the puncture movement.

For diagnostic purposes, small quantities of body fluids, such as blood, are taken from a body part. For this purpose, piercing devices having lancets are typically used, using which a wound is generated in the body part, for example, in the finger or in the ear lobe. The piercing systems are implemented in such a manner that they may also be used by laymen.
However, when determining an analyte in the body fluid, a procedure in multiple steps is required. Firstly, a wound must be generated in the body part using a piercing system, which comprises a piercing device and a lancet. A body fluid, such as blood, then exits from the wound. In a further step, the fluid must be received by a test element and supplied to an analysis system, using which the desired analyte in the body fluid is determined.

This procedure is complex, in particular for diabetics, who must determine the glucose content in the blood multiple times a day.
Therefore, in addition to pain-free piercing as much as possible, increased operating comfort is also required.

In order to come one step closer to the desired operating comfort, integrated analysis systems have been proposed in the prior art, which also comprise an analysis unit in addition to a piercing device. An analysis system is known from WO 2006/027101 Al, in which, after the generation of the wound in the body part, the piercing device is moved away from an opening of the analysis system and an analysis unit is moved to the opening of the system in a second step, so that blood exiting from the wound can be received by the analysis unit.

In order to improve the handling ability and the comfort of the analysis systems, analysis systems have been developed which propose test elements and/or test sensors having an integrated lancet.

For example, an analysis system having a test sensor with an integrated lancet, in which an analyte in a body fluid is determined by an electrochemical measurement is known from W02006/092281. The disposable test sensor comprises a test strip, on whose top side a capillary channel is provided, which is used to transfer the received body fluid to test electrodes, which are also located on the top side of the test strip, in order to determine an analyte in the body fluid. A lancet is located on the bottom side of the test strip, which is movably mounted relative to the test strip. The lancet is enclosed by a sterile envelope, 1o from which it exits before piercing into the body part.

For the sample acquisition, the test sensor is guided into the vicinity of the opening of the analysis system. The lancet is then moved forward in the puncture direction until it exits from the opening of the receptacle system and generates a wound in a body part which is pressed against the opening. After the puncture, the lancet is retracted again until it is positioned in its sterile protective envelope again. The blood exiting from the puncture wound and/or the exiting body fluid is suctioned in by the capillary channel on the top side of the test strip and finally reaches the electrodes, so that an analyte in the body fluid may be determined electrochemically.

A system of this type has the disadvantage that two separate handling steps are necessary in order to, on the one hand, ensure the puncture in the skin and, on the other hand, ensure the transfer of a sufficiently large blood sample onto the test element.

This may be performed manually, after execution of the puncture, the analysis system being removed from the body part and the body part subsequently being "milked" in order to promote the escape of blood from the wound. As soon as a sufficiently large quantity of blood has exited from the wound, the analysis system is guided back to the wound manually in order to suction the sample into the capillary channel. This requires cumbersome handling by the patient and is difficult in particular for older people, who are frequently affected by diabetes.

Alternatively to the manual procedure and the operation comprising multiple steps, the "milking" may be mechanized by the analysis system itself. For this purpose, systems having a so-called finger cone have been proposed. After the piercing procedure, the expression of a liquid sample is caused by pressure on the cone. For this purpose, the manual handling is thus replaced by a corresponding instrument function, which requires significant design effort and makes the instruments more costly, however.

As a third, rather theoretical possibility, which is also opposed by the demand for piercing with as little pain as possible, the lancet may be pierced so deeply into the body part that a sufficiently large blood droplet exits without additional measures such as manual or mechanical milking. The pain connected with the deep piercing is so great, however, that a system of this type is unsuitable for practice.

It is thus the object of the present invention to propose an analysis system which is distinguished by a high comfort for the user, in particular in that he only has to hold the analysis system on the body part once in order to determine the desired analyte. On the other hand, the system is to be easy to operate and is to be based on a simple and cost-effective design.

The analysis system according to the invention for determining an analyte in the body fluid comprises a disposable integrated sample acquisition and analysis element, which is also referred to as a "disposable or disposable item", and a reusable analysis instrument. The disposable integrated sample acquisition and analysis element has a piercing element having a tip for generating a puncture wound in a body part and a flat test strip having a sample receiving zone, into which a body fluid sample is transferred to perform an analysis. The reusable analysis instrument comprises a coupling unit, which is adapted in order to couple a disposable integrated sample acquisition and analysis element ("disposable") to a drive, by which a puncture movement of the 5 piercing element of the disposable is driven. During a propulsion phase of the puncture movement, the piercing element is moved on a puncture path in the puncture direction. After reaching a reversal point of the puncture movement, during a retraction phase the piercing element is moved opposite to the puncture direction. In addition, the analysis io instrument comprises a measuring and analysis unit, which is adapted to measure a measuring variable which is characteristic for the determination of the analyte, and to perform a determination of the desired analysis result based on the measurement.

Reference is made hereafter to blood as an example of a body fluid, without restriction of the generality. Of course, it is also possible using the system according to the invention to determine analytes in other body fluids.

The sample receiving zone of the test strip of the disposable (throwaway) is located on one of the flat sides of the test strip. This flat side forms a sample contact side. The piercing element is located parallel to the test strip and is movable on a movement path relative to the test strip during at least a part of the puncture movement. The piercing element is located close to the sample contact side of the test strip of the disposable, i.e., on the flat side on which the sample receiving zone is located. It has a capillary channel which has a sample inlet and a sample outlet. The body fluid can enter into the capillary channel through the sample inlet after the piercing; it can exit from the channel again through the sample outlet.
The body fluid exiting from the capillary channel through the sample outlet can be transferred to the sample receiving zone, if the sample outlet is close to the sample receiving zone of the test strip. This position, in which the piercing element is positioned relative to the test strip so that the sample outlet approaches the sample receiving zone is referred to as the sample transfer position. The movement path of the piercing element therefore comprises this position.

The analysis system according to the invention and also the disposable integrated sample acquisition and analysis element are distinguished by a simple construction. If the piercing element penetrates into the body part with its tip during the puncture movement and generates a wound, body fluid may penetrate to the sample inlet into the capillary channel.
The body fluid is thus guided intentionally into the capillary channel io already upon piercing. During the retraction phase of the puncture movement of the piercing element, further body fluid also penetrates into the capillary channel and is guided thereby to the sample outlet.
According to the invention, the exit of the body fluid from the capillary channel takes place in the sample transfer position. If the piercing element is positioned in this position, at least a part of the sample outlet is located at the sample receiving zone in such a manner that the body fluid may pass from the capillary channel onto the sample receiving zone.
This transfer point is thus a defined position, so that it may be easily ensured that the body fluid reaches the sample receiving zone. It proves to be advantageous that the piercing and the receiving of the body fluid occur using the same element, namely using the piercing element.

The advantage thus results for the user of the analysis instrument that it is very simple to operate. He only has to place the instrument once on his body part, preferably on the fingertip, to perform a complete analysis.
Further handling steps of the user, such as removing the device after the puncture, mechanical milking, and putting the device back on the puncture wound to receive the exiting body fluid in a capillary channel, are dispensed with. Real "one-stop handling" is thus possible for the user. Therefore, high acceptance with the users is provided. The analysis system according to the invention is intended in particular for older people, whose fine-motor ability is weakened.

The reliable transfer of the body fluid to the sample receiving zone is supported in that the movement of the piercing element occurs on the side of the test strip which is referred to as the sample contact side and comprises the sample receiving zone. A simple and reliable transfer is thus possible.

In an advantageous embodiment, the sample acquisition is improved in that a collection movement follows the piercing movement of the piercing element, during which a body fluid sample is received in the capillary io channel of the piercing device. The movement velocity of the piercing element is less during the collection movement than during the piercing movement. The relative movement of the piercing element relative to the test strip is also to be slower during the collection movement in comparison to the puncture movement. In an especially preferred embodiment, both are moved synchronously so that their relative position is maintained. In this case, no relative movement occurs between piercing element and test strip during the collection movement.
Optionally, the piercing element also performs a transfer movement in addition to the piercing movement and the collection movement, in which the piercing element is moved into the sample transfer position, in which the transfer of the body fluid from the capillary channel to the sample receiving zone takes place. The path of all movements of the piercing element, comprising the piercing movement, the collection movement, and the transfer movement, is referred to as the movement path of the piercing element.

In a preferred embodiment of the analysis system, the analysis instrument comprises a coupling unit having two coupling mechanisms.
3o The first coupling mechanism is adapted for coupling with the piercing element, and the second coupling mechanism for coupling with the test strip. The test element and the test trip may thus be moved independently of one another, wherein both components being able to be moved simultaneously at equal or different velocities. The movements may take place relative to a housing of the piercing device, for example.

A coupling unit of this type is preferably used if the piercing element is to execute the explained collection movement. Alternatively to a coupling unit comprising two coupling mechanisms, for example, the test strip may be fixed in the housing of the analysis instrument. This is possible in simpler embodiments, for example, if the test strip does not have to be moved for the sample receiving.

The analysis system preferably comprises a stacking magazine, which may be replaceable and receives multiple disposables (sample to acquisition and analysis elements). The stacking magazine may be received in a retainer of the analysis instrument, for example, so that multiple disposables are available in the instrument. As soon as all disposables of a stacking magazine have been consumed, the magazine is replaced, in that it is removed from the retainer and replaced by a new magazine equipped with unused disposables. Optionally, the stacking magazine may also provide a receptacle for the used and consumed sample acquisition and analysis elements.

The disposables are removed individually from the stacking magazine using a transport apparatus and may be moved into a coupling position.
In this coupling position, they may be coupled by the coupling unit for reaching in a further step an operating position, for example, in which they are ready for use. The supply of the unused disposables may be automated by a suitable transport apparatus and an adapted coupling unit. The transport apparatus may also be suitable for magazining used disposables after their use again, for example, in an area provided for this purpose inside the stacking magazine.

The storing in the magazine is made easier in that the test strip of the 3o disposable is implemented as flat. The piercing element is also relatively flat, so that the entire disposable has a very low thickness in comparison to its length and width. The disposable may be stacked especially well and easily.

Optionally, the stacking magazine and/or the analysis instrument may be provided with a display, which displays either the number of still unused disposables or the already used disposables. The display may be performed in the form of numbers or other markings or indicators, as are known in the prior art. Various stacking magazines are also known in the prior art, which are suitable for use in the analysis system according to the invention, e.g., from EP 0974061 or US 6,827,899.

According to a broad aspect of the present invention, there is provided an analysis system for determining an analyte in a body fluid, comprising an integrated sample acquisition and analysis element that is disposable, which comprises a piercing element having a tip for generating a puncture wound in a body part and a flat test strip having a sample receiving zone, . into which a body fluid sample is transferred for performing an analysis, and a reusable analysis instrument, comprising a coupling unit, which is adapted to couple the integrated sample acquisition and analysis element to a drive, by which a piercing movement of the piercing element is driven, the piercing movement comprising a propulsion phase in which the piercing element is moved on a puncture path in the puncture direction and a retraction phase in which the piercing element is moved opposite to the puncture direction after reaching a reversal point of the piercing movement and further comprising a measuring and analysis unit for measuring a measurement variable characteristic for the determination of the analyte and for determining a desired analysis result on the basis of the measurement, the sample receiving zone of the test strip being located on one of its flat sides, which forms a sample contact side, the piercing element being located parallel to the test strip and being movable relative to the test strip on a movement path during at least a part of the puncture movement, the piercing element being located adjacent to the sample contact side of the test strip, the piercing element comprising a capillary channel, which has a sample inlet, through which the body fluid may enter after the piercing into the capillary channel, and a sample outlet, through which the body fluid may exit from the capillary channel, and the movement path of the piercing element comprising a sample transfer position, in which the sample outlet is adjacent to the sample receiving zone of the test strip in such a manner that the body fluid is transferred from the capillary channel through the sample outlet to the sample receiving zone, wherein the sample receiving zone is adjacent to a front end of the test strip in the puncture direction, and wherein the piercing element is positioned in the puncture direction behind the sample receiving zone in such a manner that the sample receiving zone is located between the piercing element and the front end of the test strip.

9a According to a further broad aspect of the present invention, there is provided a disposable integrated sample acquisition and analysis element that is a component of a system according to any one of claims 1 to 11, which comprises a piercing element having a tip for generating a puncture wound in a body part and a flat test strip having a sample receiving zone, into which a body fluid sample is transferred to perform an analysis, the sample receiving zone of the test strip being located on one of its flat sides, which forms a sample contact side, the piercing element being located parallel to the test strip and being movable relative to the test strip on a movement path, the piercing element being located adjacent to the sample contact side of the test strip, the piercing element having a capillary channel, which has a sample inlet, through which the body fluid may enter into the capillary channel after the puncture, and a sample outlet, through which the body fluid may exit from the capillary channel, and the piercing element being movable into a sample transfer position, in which the sample outlet is adjacent to the sample receiving zone of the test strip in such a manner that the body fluid is transferred to the sample receiving zone, wherein the sample receiving zone is adjacent to a front end of the test strip in the puncture direction, and the piercing element is positioned in the puncture direction behind the sample receiving zone in such a manner that the sample receiving zone is located between the piercing element and the front end of the test strip.

The invention is explained in greater detail hereafter on the basis of preferred embodiments which are illustrated in the figures. The special features illustrated therein may be used individually or in combination to provide preferred embodiments of the invention. In the figures:

Figure 1 shows an analysis system comprising an analysis instrument and an integrated sample acquisition and analysis element;

Figures 2a to d show an exploded illustration of the sample acquisition and analysis element from Figure 1;

Figures 3a,b show an alternative embodiment of a sample acquisition and analysis element;

Figures 4a to 4h show a schematic sectional illustration of a part of the piercing system from Figure 1 in eight usage positions;

Figure 5 shows an alternative embodiment of a sample acquisition and analysis element;

9b Figure 6 shows a further embodiment of an analysis instrument; and Figure 7 shows a detailed view of the front end of a sample acquisition and analysis element.

The location specifications "front" and "rear" used hereafter relate to the puncture direction, in which the piercing element is moved to generate a wound in a body part. The front end of the piercing element is thus the end which, upon movement of the piercing element in the puncture direction, is adjacent to a housing opening, to which a body part may be pressed against to generate a wound.

Figure 1 shows an analysis system 1 comprising an analysis 5 instrument 2 and a disposable integrated sample acquisition and analysis element, which is referred to as a disposable 3. The disposable 3 partially projects out of an opening 4 of a housing 5 of the analysis instrument 2. Operating elements for operating and controlling the analysis instrument 2 are located on the top side 5a of the housing 5.
Figures 2a to d and 3 show various embodiments of a disposable 3. In a first embodiment, the disposable 3 comprises an elongated test strip 6, a piercing element 7, and a cover part 8. The test strip 6, whose length is preferably three to four times greater than its width, has a sample receiving zone 10 on one of its two flat sides 9. This flat side 9 is referred to as the sample contact side 11. The sample receiving zone 10 is preferably located in the front area of the test strip 6. The part of the test strip 6 which is close to the front end of the test strip in the puncture direction is referred to as the front area. This area may begin directly at the front end of the test strip; however, it may also be spaced apart from the front edge. In any case, the sample receiving zone 10 is located closer to the front end of the test strip than the rear end.

The test strip has a longitudinal groove 12 approximately in the middle, which extends in the longitudinal direction. The longitudinal groove 12 is used as a passage of a coupling mechanism, which moves the piercing element 7.

A hole 12a is located in the area of the far end of the test strip 6, which is preferably implemented as an oblong hole and extends transversely to the puncture direction in the test strip 6. This hole 12a is used to couple a coupling mechanism on the test strip 6, in order to move the test strip 6 in the analysis instrument 2 and/or to position or fix it.

The piercing element 7 is enclosed by a protective envelope 13, such as a thin sealing film. The protective envelope 13 preferably comprises a film which can be torn easily and can be torn further easily, so that before or at the beginning of the piercing movement, the tip 15 of the piercing element 7 may pierce through the protective envelope 13, in order to exit therefrom. During the production process of the disposable 3, the piercing element 7 may be hermetically enclosed separately by the protective envelope 13 and subsequently sterilized, so that it may be stored aseptically.
The preferably flat piercing element 7 has a needle element 14 having a tip 15 on its front end, which generates a puncture wound in the body part during the puncture movement when it hits the skin of a body part.
The piercing element 7 has a coupling recess 16, in which a coupling element may engage for coupling on a drive unit. The coupling recess 16 is preferably an elongated hole.

The needle element 14 of the piercing element 7 has a capillary channel 17 on its bottom side. In this preferred embodiment, the capillary channel 17 is oriented toward the sample receiving zone 10 of the test strip 6.

The disposable 3 is constructed like a sandwich, the piercing element 7 having the protective envelope 13 being located between the cover part 8 and the test strip 6. The cover part 8 is open in the puncture direction, so that a coupling element which is coupled from the top side (top layer) on the piercing element 7 may be moved on the movement path jointly with the piercing element 7 in the puncture direction. The cover part 8 lies on top on the protective envelope 13 on the test strip 6, in order to improve the stacking ability of the disposable 3. The piercing element 7 is not retained, however, so that it may move in the longitudinal direction of the disposable 3. Because the cover part 8 does not touch the piercing element 7, no guiding of the piercing element 7 occurs. The U-shaped cover part 8 has a hole 18 in its base. It corresponds to the hole 12a, so that the disposable 3 may be held and moved by a coupling unit which extends through the holes 12a, 18.

In an alternative embodiment of the disposable according to Figure 3, the protective envelope and the cover part are formed from a contoured main film 19 and a cover film 20. The main film 19 is formed from a base, on which a U-shaped spacer part made of film rests. The base and the spacer part are integrally connected to one another. The piercing element 7 is located between the two U-legs of the spacer part, which lo form spacers 21. The piercing element is preferably thus enclosed at least on its longitudinal sides by spacers 21, whose thickness is at least as great as the thickness of the piercing element 7. The dimension perpendicular to the sample contact side 11 of the test strip 6 is defined as the thickness. In this way, upon the joining of the main film 19 and the cover film 20, a protective envelope 13 having a cavity is formed, in which the piercing element 7 is movable. The main film 19 and the cover film 20 are preferably implemented integrally, the front part of the main film 19 used as the cover film 20 being wrapped around so that it rests on the main film 20 and the wraparound edge being located on the front side in the puncture direction. The two films may then be glued to one another on the three remaining open sides. The piercing element 7 passes through the turned-over edge on its puncture path, so that the piercing element does not have to exit through any of the glued sides.

In this embodiment, the piercing element 7 is spaced apart from the sample contact side 11 of the test strip 6 by the thickness of the base of the main film 19. The piercing element 7, which is preferably implemented as flat, has a bottom side 22 shown in Figure 3a, which faces toward the sample contact side 11. The bottom side 22 is preferably spaced apart from the sample receiving zone 10 in such a manner that the piercing element 7 does not touch the sample receiving zone 10 at least during the propulsion phase of the piercing movement.
The spacing between the bottom side 22 and the sample receiving zone 10, which is defined perpendicular to the flat side 9 of the piercing element 7, must be such that even if the piercing element 7 is located directly above the sample receiving zone during the piercing movement, an intermediate space exists. Thus, on the one hand, the piercing element 7 is prevented from rubbing along the sample receiving zone 10 and damaging it, on the other hand, the piercing movement of the piercing element 7 is prevented from being influenced by friction, in particular in that the piercing element 7 is braked.

Figure 3b shows the piercing element 7 viewed from its bottom side 22.
The capillary channel 17 extends from the tip 15 of the piercing element along the needle element 14 up to its main body. The capillary channel 17 has a sample inlet 23, through which the body fluid may penetrate after the puncture into the capillary channel 17. The sample inlet 23 is located on the tip 15. On the end of the capillary channel 17 which is opposite to the sample inlet 23, the capillary channel 17 has a sample outlet 24, through which the body fluid may exit from the capillary channel 17. In the embodiment shown, the capillary channel 17 is open on one side, so that a grooved capillary channel 17 is formed. The open top side of the capillary channel 17, implemented here as a semi-cylinder, thus represents the sample inlet 23 and the sample outlet 24, which merge into one another. The sample inlet 23 and the sample outlet 24 are thus not only limited to the two ends of the capillary channel 17.

The disposable shown in Figures 2 and 3 is distinguished in that it is especially flat. It may be stacked well and may therefore be magazined easily.

Figures 4a to h schematically show the front end of the analysis instrument 2 during different movement phases of the disposable 3.
Figure 4a shows the disposable 3 in a coupling position, after the disposable 3 has been removed from a stacking magazine (not shown here). In the coupling position, the disposable 3 is coupled by a coupling unit. The coupling unit has a first coupling mechanism 25 for coupling with the piercing element 7, which is implemented in the form of a mandrel 26. The mandrel 26 engages through the coupling recess 16 of the piercing element 7. The mandrel 26 also extends in the longitudinal groove 12 of the test strip 6, in which it may move during the puncture movement of the piercing element 7. Upon insertion of the mandrel 26 into the coupling recess 16 and the longitudinal groove 12, the protective envelope 13 implemented as a film is pierced. Up to this moment, the piercing element 7 is sterile in its protective envelope 13.

A second coupling mechanism 27 is preferably also implemented as a mandrel 28. The mandrel 28 is guided in such a manner, preferably simultaneously with the mandrel 26, that it pierces into the hole 18 of the protective envelope 13 and the corresponding hole 12a of the test strip.
In this way, the test strip 6 may be retained and guided so that the test strip 6 may also perform a movement in and opposite to the puncture direction. The coupling mechanisms 25 and 27 of the coupling unit allow the coupling of the disposable 3 on a drive unit (not shown here), using which the movement of the piercing element 7 and of the test strip 6 is driven.

Because the protective envelope 13 is very thin and has little tear resistance, it offers no resistance to the mandrels 26, 28. The coupling of the disposable 3 to the coupling unit is not obstructed.

In the coupling position according to Figure 4a, the disposable 3 is still far enough from the opening 4 of the housing 5 that a body part pressing against the opening 4, such as a fingertip 29, which bulges into the opening 4, does not come into contact with the disposable 3. Of course, the housing 5 of the analysis system and the opening 4 may be implemented in such a manner that the fingertip 29 does not bulge into the inner chamber of the analysis instrument 2.

At the beginning of the puncture procedure, the mandrel 28 of the second coupling mechanism 27 is moved in the direction toward the opening 4, whereby the test strip 6 is moved far enough in the puncture direction that the front end 30 of the test strip 6 presses against the fingertip 29.

This front end 30 in the puncture direction is preferably implemented as a skin contact surface 31. In a special embodiment, the front edge 32 of the test strip 6 is the skin contact surface 31. Preferably, the skin contact surface 31 presses against the body part at least during a part of the 5 movement path of the piercing element and is used as a piercing depth reference element 33 for the propulsion phase of the piercing movement.
A predetermined value of the piercing depth is determined by the distance in the puncture direction between the skin contact surface 31 and the position of the tip 15 of the piercing element 7 at the reversal 1o point of the piercing movement. A desired piercing depth of the piercing element 7 into the fingertip 29 may thus be set and changed.

After or simultaneously with the movement of the mandrel 28, the mandrel 26 of the first coupling mechanism 25 is also moved in the 15 puncture direction so that the piercing element 7 is moved along a part of its movement path in the puncture direction. The protective film 13 is torn open further by the mandrel 26. On its front end, it is penetrated by the tip 15 of the piercing element 7. The piercing element 7 is preferably moved in the puncture direction until the tip 15 of the piercing element 7 is positioned at the front edge of the sample receiving zone 10. The tip 15 is preferably located approximately 0,5 mm distant from the front edge 32 of the test strip 6 so that the test strip 6 projects beyond the piercing element.

Figures 4a and 4b show that the user presses his fingertip 29 on the analysis instrument 2 before the disposable 3 is moved into its starting position (Figure 4b). Alternatively, the movement of the disposable 3 from the coupling position into the start position may also occur first. After this the user presses his fingertip 29 against the opening 4 of the analysis instrument 2, until the fingertip 29 contacts the skin contact surface 31.
Before a piercing may occur, for example, it must be electronically checked that the fingertip touches the skin contact surface 31. Optionally, the disposable 3 may also be mounted spring-loaded in the analysis instrument in this embodiment.

During the propulsion phase of the puncture shown in Figure 4c, the first coupling mechanism 25 is moved in the longitudinal groove 12 in the puncture direction until the tip 15 of the piercing element penetrates into the fingertip and generates a puncture wound. In this preferred embodiment, the tip 15 of the piercing element 7 is thus moved during the propulsion phase of the piercing movement beyond the front end 30 of the test strip 6 in the puncture direction.

As soon as the set piercing depth is reached, the retraction phase of the piercing element 7 begins, during which the mandrel 26 of the coupling mechanism 25 is moved opposite to the puncture direction. Only the mandrel 26 and the piercing element 7 are moved during the entire puncture, which takes place at a very high velocity. Thus, a rapid relative movement of the piercing element 7 to the test strip 6 takes place, the mandrel 26 being moved relative to the mandrel 28. The test strip 6 itself is preferably not moved or is only moved very slowly during the piercing, so that the skin contact surface 31 of the test strip 6 contacts the fingertip 29 and thus exerts a pressure on the fingertip.

A collection movement preferably follows the piercing movement of the piercing element 7. During the collection movement the relative movement between the piercing element 7 and the test strip 6 is significantly slower than in the piercing movement. Alternatively, no relative movement occurs at all. The piercing element 7 and the test strip 6 are moved synchronously with one another. Alternatively, the test strip 6 of the disposable 3 may remain in its position.

If the test strip 6 is also moved opposite to the puncture direction during the collection movement, the pressure exerted by the skin contact surface 31 on the fingertip is reduced. The blood is thus encouraged to exit from the wound. The blood may penetrate into the capillary channel 17 of the piercing element 7. An effective "collection" of blood may thus be implemented. Manual and/or mechanical "milking" is not necessary. The skin contact surface 31 is thus used as an expression aid in this case.

During the collection movement of the piercing element shown in Figure 4d, the blood exits out of the puncture wound through the sample inlet 23 into the capillary channel 17. The blood is moved along the channel in the direction toward the sample outlet 24 by the capillary action.
At the end of the collection movement, which is shown in Figure 4e, the disposable 3 is moved far enough from the opening 4 that there is no longer contact with the fingertip 29. The fingertip 29 may be taken away from the opening 4. The collection movement is completed. The capillary 1o channel 17 is filled with blood.

In the example shown, the tip 15 of the piercing element 7 has a protrusion in relation to the test strip 6, which is preferably maintained at least in the last part of the collection movement.
Following the collection movement, the piercing element 7 is moved in a transfer movement into the sample transfer position, as shown in Figure 4f. The mandrel 26 is moved in relation to the mandrel 28 therein until the tip 15 of the piercing element 7 approximately corresponds to the front edge of the sample receiving zone 10.

In addition, the disposable 3 is moved away from the housing opening until it reaches a position in which the sample receiving zone 10 is positioned in the area of a contact pressure apparatus 34 of the analysis instrument 2. This movement is caused by a movement of the mandrel 26. The movement of the disposable 3 may take place before, after, or simultaneously with the movement of the piercing element 7 described above.

In the sample transfer position of the piercing element shown in Figures 4f and 4g, the sample outlet 24 of the capillary channel 17 is adjacent to the sample receiving zone 10 in such a manner that blood from the capillary channel 17 may be transferred through the sample outlet 24 to the sample receiving zone 10. The capillary channel 17 is located on the bottom side of the piercing element 7, i.e., on the side facing toward the sample contact side 11 of the test strip 6. The sample outlet 24 is positioned directly above the sample receiving zone 10. A simple transfer of the blood is possible. The capillary channel 17 is preferably open on one side in such a manner that its opening is oriented toward the sample receiving zone 10.

The piercing element 7 is preferably spaced apart from the test strip 6 in the direction of the perpendicular to the sample contact side 11 in such a manner that the piercing element 7 does not touch the sample receiving 1o zone 10. The piercing element 7 is now pressed, in the sample transfer position, from above (in the direction of the arrow) against the sample receiving zone 10by a plunger 35 of the contact pressure apparatus 34.
The sample outlet 24, which is formed by one part of the one-sided opening of the capillary channel 17, is moved to the sample receiving zone 10 so that the blood is reliably transferred.

A measuring and analysis unit 36, which preferably comprises an optical measuring unit 37, is located opposite to the contact pressure apparatus 34 (under the disposable 3). The optical measuring apparatus 37 is advantageously located on the bottom side of the test strip 6. It is used for performing a photometric measurement, in order to measure an optically measurable measurement variable, which is characteristic for the determination of the analyte in the body fluid and in the blood, respectively.
Figure 7 shows in detail the front end 30 of the disposable 3 having the sample receiving zone 10, against which the measuring apparatus 37 presses. The sample receiving zone 10 preferably comprises a test field 38, which comprises at least one absorbent layer 39. The test field 38 has a sample receiving surface 40 on the sample contact side 11 of the test strip 6 and a detection surface 41 on the bottom side, which is opposite to the sample contact side 11. In the preferred embodiment of the disposable 3, the sample receiving zone 10 and the test field 38 are identical. However, it is also possible that the test field 38 and the sample receiving zone 10 deviate from one another, so that the detection surface 41 for the optical measurement of the characteristic measurement variable is spatially separated from the sample receiving surface 40.

The photometric measurement using the optical measuring apparatus 37 preferably occurs by diffuse reflection on the detection surface 41. The detection surface 41 is especially preferably in fluid connection with the test field 38 and/or the sample receiving zone 10. Diffuse reflection is understood as a measurement using a measuring configuration, in which 1o the angle of incidence of an (electromagnetic) wave (e.g., light) is different from the exit angle after incidence on the detection surface 41.
Because the optical measurement occurs on the bottom side, i.e., on the side opposite to the sample contact side 11 of the test strip 6, pigments which are contained in the blood, for example, do not corrupt the measurement result. These pigments remain in the absorbent layer 39 and/or on the sample receiving surface 40. Suitable embodiments of test fields 38 of this type are generally known in the prior art.

After the photometric measurement has been performed in the sample transfer position of the piercing element 7, the piercing element 7 is moved relative to the test strip 6 in the direction of the rear end of the disposable 3 until the piercing element 7 is located in its starting position again, in which it is completely retracted into the (partially damaged) protective envelope 13, Figure 4h.

The disposable 3 is then moved back into the coupling position, from which it may then be moved by a transport apparatus back into the stacking magazine and into a receptacle container for consumed disposables, respectively.

Figure 5 shows a schematic illustration of a further embodiment of the disposable 3. The test strip 6 of the disposable is preferably implemented so that the length of the disposable, i.e., the dimension in the puncture direction, may be varied by breaking or cutting off the front end 30 of the test strip 6. Different piercing depths may thus be set, without having to provide a further piercing depth setting device in the analysis instrument 2. Multiple markings and/or perforations of the test strip 6 are located in the area of the front end 30, at which the disposable 3 may be 5 shortened in such a manner that the piercing depth may be set individually during the puncture procedure. Each marking or perforation corresponds to a predetermined piercing depth. The individual piercing depth setting is thus performed by a length change on the disposable 3.

10 In a preferred embodiment, a sample receiving zone 10 is also provided in this type of disposable, the markings or perforations for shortening the disposable not extending up into the sample receiving zone 10. Even upon setting of the greatest piercing depth (shortest test strip 6), the sample receiving zone 10 is spaced apart from the front edge 33 of the 15 disposable.

In order to achieve the most precise possible setting of the piercing depth, in an embodiment of the analysis system 1 according to Figure 6, a shortening unit 42 is provided, which is integrated laterally in the 20 analysis system 1, for example. The preferred shortening unit 42 is used to shorten the test strip 6 on its front end 30 in the puncture direction, in order to set the desired piercing depth during the puncture.

Alternatively, the shortening unit 42 may be integrated in the analysis system in such a manner that a disposable 3 transported out of a stacking magazine may be shortened automatically to a settable length.
The desired length, which corresponds to a piercing depth, may be set by the user of the analysis instrument on a setting device, for example.

Claims

1. Analysis system for determining an analyte in a body fluid, comprising - an integrated sample acquisition and analysis element that is disposable, which comprises a piercing element having a tip for generating a puncture wound in a body part and a flat test strip having a sample receiving zone, into which a body fluid sample is transferred for performing an analysis, and - a reusable analysis instrument, comprising a coupling unit, which is adapted to couple the integrated sample acquisition and analysis element to a drive, by which a piercing movement of the piercing element is driven, the piercing movement comprising a propulsion phase in which the piercing element is moved on a puncture path in the puncture direction and a retraction phase in which the piercing element is moved opposite to the puncture direction after reaching a reversal point of the piercing movement and further comprising a measuring and analysis unit for measuring a measurement variable characteristic for the determination of the analyte and for determining a desired analysis result on the basis of the measurement, - the sample receiving zone of the test strip being located on one of its flat sides, which forms a sample contact side, - the piercing element being located parallel to the test strip and being movable relative to the test strip on a movement path during at least a part of the puncture movement, - the piercing element being located adjacent to the sample contact side of the test strip, - the piercing element comprising a capillary channel, which has a sample inlet, through which the body fluid may enter after the piercing into the capillary channel, and a sample outlet, through which the body fluid may exit from the capillary channel, and - the movement path of the piercing element comprising a sample transfer position, in which the sample outlet is adjacent to the sample receiving zone of the test strip in such a manner that the body fluid is transferred from the capillary channel through the sample outlet to the sample receiving zone, - wherein the sample receiving zone is adjacent to a front end of the test strip in the puncture direction, and - wherein the piercing element is positioned in the puncture direction behind the sample receiving zone in such a manner that the sample receiving zone is located between the piercing element and the front end of the test strip.

2. Analysis system according to claim 1, characterized in that the measuring and analysis unit comprises an optical measuring apparatus, for measuring by means of a photometric measurement an optically measurable measurement variable which is characteristic for the determination of the analyte.

3. Analysis system according to claim 1 or 2, characterized in that the sample receiving zone contains a test field, comprising at least one absorbing layer and having a sample receiving surface on the sample contact side of the test strip and a detection surface on the side of the test strip opposite to the sample contact side.

4. Analysis system according to any one of claims 1 to 3, characterized in that the tip of the piercing element is disposed beyond the front end of the test strip in the puncture direction when the piercing element has been moved on the puncture path by the propulsion phase of the piercing movement.

5. Analysis system according to any one of claims 1 to 4, characterized in that the piercing element performs a collection movement, in which a relative movement slower than the piercing movement or no relative movement of the piercing element relative to the test strip takes place.

6. Analysis system according to any one of claims 4 and 5, characterized in that the body fluid sample is received in the capillary channel of the piercing element.

7. Analysis system according to any one of claims 1 to 6, characterized in that the analysis instrument has a contact pressure device, by which the piercing element is pressed against the sample receiving zone, when in the sample transfer position, thereby to transfer the body fluid to the sample receiving zone.

8. Analysis system according to any one of claims 1 to 7, characterized in that the front end of the test strip in the puncture direction comprises a skin contact surface and is used as a piercing depth reference element, a predetermined value of the piercing depth being determined by the spacing in the puncture direction between the skin contact surface and the position of the tip of the piercing element at the reversal point of the piercing movement.

9. Analysis system according to claim 8, characterized in that a shortening unit is integrated in the analysis system, for reducing the length of the test strip at its front end in the puncture direction.

10. Analysis system according to any one of claims 1 to 9, characterized in that the coupling unit comprises a first coupling mechanism for coupling to the piercing element and a second coupling mechanism for coupling to the test strip.

11. Analysis system according to any one of claims 1 to 10, characterized in that a plurality of sample acquisition and analysis elements are stored in a stacking magazine, which elements are removed individually from the stacking magazine and moved into a coupling position by means of a transport apparatus.

12. Disposable integrated sample acquisition and analysis element that is a component of a system according to any one of claims 1 to 11, which comprises a piercing element having a tip for generating a puncture wound in a body part and a flat test strip having a sample receiving zone, into which a body fluid sample is transferred to perform an analysis, - the sample receiving zone of the test strip being located on one of its flat sides, which forms a sample contact side, - the piercing element being located parallel to the test strip and being movable relative to the test strip on a movement path, - the piercing element being located adjacent to the sample contact side of the test strip, - the piercing element having a capillary channel, which has a sample inlet, through which the body fluid may enter into the capillary channel after the puncture, and a sample outlet, through which the body fluid may exit from the capillary channel, and - the piercing element being movable into a sample transfer position, in which the sample outlet is adjacent to the sample receiving zone of the test strip in such a manner that the body fluid is transferred to the sample receiving zone, wherein - the sample receiving zone is adjacent to a front end of the test strip in the puncture direction, and - the piercing element is positioned in the puncture direction behind the sample receiving zone in such a manner that the sample receiving zone is located between the piercing element and the front end of the test strip.

13. Analysis system according to any one of claims 1 to 11 or disposable integrated sample acquisition and analysis element according to claim 12, characterized in that the capillary channel of the piercing element has a longitudinal opening, which is open in the radial direction and extends over at least a part of its length, the opening being oriented toward the sample contact side of the test strip.

14. Analysis system according to any one of claims 1 to 11 or disposable integrated sample acquisition and analysis element according to any one of claims 12 or 13, characterized in that the piercing element is enclosed by a protective envelope, which is adapted to be penetrated during the puncture movement.

15. Analysis system according to any one of claims 1 to 11 or disposable integrated sample acquisition and analysis element according to any one of claims 12 to 14, characterized in that the piercing element is enclosed at least on its longitudinal size by spacers, whose thickness is at least as great as the thickness of the piercing element.

16. Analysis system according to any one of claims 1 to 11 or disposable integrated sample acquisition and analysis element according to any one of claims 12 to 15, characterized in that the piercing element is implemented as flat and a bottom side of the piercing element, which faces toward the sample contact side, and the sample receiving zone and piercing element are spaced apart without touching at least during the propulsion phase of the piercing movement.

17. Analysis system according to any one of claims 1 to 11 or disposable integrated sample acquisition and analysis element according to any one of claims 12 to 16, characterized in that the test strip is adapted for reducing its length by breaking or cutting off the front end of the test strip, thereby to set different piercing depths.