Abstract:
Disclosed is the sensing a sample fluid. The sample fluid is first provided into a cartridge ( 400 ), and the cartridge ( 400 ) inserted into a reading device ( 420 ). A pressure variation is provided in the cartridge ( 400 ), and the sample fluid will be moved to a sensing element ( 140 ) by using the provided pressure variation and by controlling the timing for releasing a pressure in the pressure variation means ( 40, 50, 100, 110 ). The moved the sample fluid can then be sensed by means of the sensing element ( 140 ).

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to transport of fluids, in particular for body-fluid analysis purposes.  
           [0002]    Testing of blood, or other body fluids, for medical evaluation in diagnosis has traditionally been domain of central laboratories offering efficient, reliable and accurate testing of a high volume of fluid samples. Samples must be collected, transported to the laboratory, analyzed and the result has then to be communicated back. This often produces delays of several days between sample collection and communication of the test results.  
           [0003]    U.S. Pat. No. 5,096,669 discloses a system with a disposable device and a hand-held reader, which can perform a variety of electrochemical measurements on blood or other fluids. In operation, a fluid sample is drawn into the disposable device through an orifice by capillary action. The orifice is sealed off and the disposable device is inserted into the reader. The reader which controls the test sequence and flow of fluid causes a calibrant pouch located inside the device to be pierced, releasing the calibrant fluid to flow across the sensor arrays to perform calibration. Next, an air bladder located in the device is depressed, forcing the sample across the sensors where measurements are performed and read by the reader which performs the calibrations. Once the measurements are made, the device can be withdrawn from the reader and discarded. While in the first step the fluid sample has to be manually inserted into the disposable device, the reader further controls displacing the calibrant fluid as well as the fluid sample within the disposable device.  
           [0004]    A further system, the IRMA SL Blood Analysis System, introduced by Agilent Technologies, also applies a disposable cartridge for analyzing body fluids in conjunction with a portable reading and evaluation unit. After inserting the cartridge into the reader, a calibration process of the sensor element within the cartridge by means of a calibration gel already situated on the sensor elements is initiated. When the calibration process has been finalized, the blood or other fluid sample has to be manually inserted into the cartridge during a defined time frame by means of a capillary-syringe collection device.  
         SUMMARY OF THE INVENTION  
         [0005]    It is object of the present invention to further improve fluid transport in fluid analysis systems, in particular in cartridge-based fluid analysis systems e.g. for analyzing blood or other body fluids. The object is solved by the independent claims. Preferred embodiments are shown by the dependent claims.  
           [0006]    According to the invention, pressure variation is used for moving one or more fluids. The pressure variation can be applied e.g. for moving a calibration fluid or gel, and/or for moving a fluid sample to be analyzed. In a cartridge-based fluid analysis system, the pressure variation is preferably introduced to the cartridge, preferably during insertion of the cartridge into a reading device, for moving one or more fluids within the cartridge.  
           [0007]    The pressure variation can be an applied underpressure, overpressure, or a combination of underpressure and overpressure applied successively or in parallel to each other. Underpressure can be used for drawing the fluid, while overpressure might be applied for pushing the fluid, in particular when those fluids are moved in a capillary system.  
           [0008]    The term ‘capillary system’ as used for the purpose of this invention shall mean any system applying capillary forces in order to keep fluids in position and/or to direct or move fluids in a predetermined way/direction, and shall cover any kind of shaping of the capillary channels, such as round, elliptical, square, etc. and combinations thereof.  
           [0009]    The term ‘drawing’ the fluid shall represent a situation where the fluid-moving force is substantially resulting from a ‘location ahead of the fluid’ in the direction of movement. This can be achieved e.g. by applying a suction force and/or using the principle of a water jet pump. The term ‘pushing’ the fluid, accordingly, shall represent a situation where the fluid-moving force is substantially resulting from a ‘location behind the fluid’ with respect to the direction of movement. This can be achieved e.g. by applying an overpressure to an air bladder (or air bubbles) ‘behind’ the fluid in a capillary, thus moving the fluid in the direction in the direction of the applying force on the air bladder.  
           [0010]    A combination of overpressure and underpressure allows achieving a two- or more-step process, wherein e.g. in a first step fluid is moved under influence of the overpressure by pushing the fluid. Preferably by applying valve systems, releasing the overpressure by pushing the fluid can be used for setting up an underpressure. Releasing the underpressure might then be used for transporting this or a different fluid, e.g. by drawing the fluid under influence of the underpressure. In such a two-step approach, the first step for transporting under influence of overpressure can be applied for moving a calibration fluid/gel to or away from the sensors. The second step of transporting fluid under the influence of underpressure can then successively be applied for moving the sample fluid to be analyzed to or away from the sensors. However, it is clear, that both steps can also be applied individually and independently of each other.  
           [0011]    The pressure variation can be caused preferably by a manual activation, such as manually pressing, pushing or pulling by hand, or by an automatic activation controlled e.g. by the reading device. The pressure variation process is preferably initiated when a cartridge is coupled to or inserted into the reading device. In case of manual activation, the user might then be prompted to execute the manual activation (e.g. pushing on a press button). In case of automatic activation, the reading device might start the activation after the cartridge has been coupled to or inserted. This might be in conjunction with a process for locking the cartridge against prematurely removing from the reading device. In this case, means for locking the cartridge might be applied for pushing e.g. a suitable press button, thus locking the cartridge and concurrently activating the pressure variation.  
           [0012]    In a preferred embodiment, the pressure variation is accomplished by a volumetric decrease and/or increase. For that purpose, the cartridge preferably comprises a pressure chamber which can be compressed, thus decreasing or increasing the volume of the pressure chamber. The volumetric decrease/increase leads to an overpressure/underpressure within the pressure chamber. The overpressure/underpressure in the pressure chamber can then be applied for fluid moving or simply be released, dependent on the specific application.  
           [0013]    The pressure chamber may have several separated chambers, so that a pressure variation can be applied to one or more of the chambers concurrently of successively. Preferably, all chambers can be decreased/increased in volume in one step, but might be released with different timings, e.g. successively. Such an embodiment allows to accomplish different timing steps e.g. for calibration and/or measurement.  
           [0014]    It is technically clear that the term ‘chamber’ as used herein is to be understood in its broadest sense and does not require a specific or separated room solely for the purpose of pressure activation. The term ‘chamber’ shall simply denote any kind of physical ‘room’ that allows to at least temporarily changing the pressure conditions against its environment. Chamber thus can mean e.g. an entire conduit system but also a more or less separated room only.  
           [0015]    The pressure chamber preferably comprises a resilient member, such as a membrane and/or a rubber bellow preferably e.g. supported by a spring mechanism, which will then counteract a force applied onto the resilient member in order to decrease/increase volume of the pressure chamber. Once the resilient member has been pressed down for volumetric compression or pulled out for volumetric expansion, the resilient member will then try to return into its initial position. This can then be used for providing an underpressure/overpressure in the pressure chamber after the overpressure/underpressure in the pressure chamber has been released. In other words, as soon as the overpressure/underpressure will be released, as long as the resilient member is pressed down/pulled up, the reverse movement of the resilient member will lead to a volumetric increase/decrease, thus building up an underpressure/overpressure within the pressure chamber. The change between overpressure and underpressure within the pressure chamber is preferably supported by means of adequate valve means. Releasing the underpressure/overpressure in the pressure chamber may then be applied for fluid movement, e.g. by drawing and/or pushing the fluid in a corresponding conduit system.  
           [0016]    In a further preferred embodiment, the overpressure achieved by pressing down the resilient member of the pressure chamber will be immediately used for a first fluid movement, preferably for moving the calibration fluid to or away from the sensor elements. This can be achieved in that the overpressure in the pressure chamber will be (preferably immediately) released, thus pushing the fluid(s) in a capillary system such as a conduit system. Once the overpressure is released, the resilient member wants to return in its initial position. As long as the gas flow into the pressure chamber will be limited or completely avoided, e.g. by means of a valve or a mechanical spring load, this will lead to a constant or slowly decreasing underpressure in the pressure cell. Opening the valve or releasing the spring load will then release the underpressure in the pressure chamber, which can be applied for further fluid movements, preferably for moving the sample fluid to the sensor elements. The above applies accordingly when first an underpressure is generated e.g. by pulling out the resilient member.  
           [0017]    Controlling the point in time for releasing the pressure (underpressure or overpressure) in the pressure chamber can be applied for controlling a timing sequence e.g. of calibration and measuring processes. This in particular is useful since most systems require a certain calibration time (e.g. some seconds up to two minutes) until the analysis system is ready for measuring the fluid sample. The timing sequence is preferably defined by controlling a valve system e.g. by means of mechanical or electrical timing means. Electrical timing means can be, for example, an electrical current subjected to the valve, which will eventually destroy or otherwise open the valve, thus releasing the pressure in the desired way. Mechanical timing means can be, for example, springs or pistons.  
           [0018]    Releasing the pressure can be provided substantially instantaneous, i.e. in a time relatively short with respect to a time for providing or maintaining the pressure, or substantially continuously, i.e. in a time relatively long with respect to a time for providing or maintaining the pressure. In the former case, a valve might simply open up against environment, whereby the dimension of the opening against the environment is preferably selected in a way that substantially no flow restriction occurs. In the latter case, the dimension of the opening against the environment of the valve might be selected that flow restriction is dominating, so that a pressure balance between the pressure chamber and the environment will take some time.  
           [0019]    Releasing the pressure in the pressure chamber can be preferably controlled in a way that movement of the sample fluid to the sensor elements will first be allowed after the calibration process has been finalized. In one embodiment, the pressure control is provided by the reading device, e.g. in that the reading device sends a signal or initiates e.g. a mechanical action after it has sensed the calibration process is done. In a further embodiment, the pressure control is provided by the cartridge independently of the reading device. This can be achieved e.g. by an electrical and/or mechanical timer system such as a clock or winded up mechanical clock.  
           [0020]    Instead of controlling the sample fluid movements under consideration of the actual state of the calibration process, a fixed timing can be defined, so that the pressure will be released after a fixed period of time, independent of the actual state of the calibration process. By defining this fixed time period to cover at least the maximum expected calibration time, it can be made sure that the calibration process can be completely and independently executed and that no interference of the measurement process with the calibration process occurs.  
           [0021]    It is clear that the invention can be partly or entirely embodied by one or more suitable software programs, which can be stored on or otherwise provided by any kind of data carrier, and which might be executed in or by any suitable data processing unit. Such software programs might be used, in particular, for controlling timing of the fluid movement, application of the pressure variation, and/or analyzing the fluids. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    Other objects and many of the attendant advantages of the present invention will be readily appreciated and become better understood by reference to the following detailed description when considering in connection with the accompanied drawings. Features that are substantially or functionally equal or similar will be referred to with the same reference sign(s).  
         [0023]    [0023]FIGS. 1 and 2 show examples of an embodiment of a fluid movement system  10  according to the invention,  
         [0024]    FIGS.  3 A-E illustrate details of an example for the pressure generation scheme,  
         [0025]    FIGS.  4 A-E illustrate details of an example for providing a timing scheme for releasing pressure, and  
         [0026]    [0026]FIG. 5 shows an application of the invention for fluid movement into a cartridge  400  to be inserted into a reading device  420 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]    [0027]FIG. 1 shows a first example of an embodiment of a fluid movement system  10  according to the invention. The fluid movement system  10  is preferably used for analyzing body fluids, in particular blood. However, it is clear, that the principles of the invention can be applied accordingly to any other system wherein fluids have to be moved, e.g. in a capillary system.  
         [0028]    The fluid movement system  10  comprises a pressure generation unit  20  and a fluid movement area  30 . The pressure generation unit  20  comprises a rubber bellow  40  supported by a spring  50 . In this example, the spring  50  surrounds the rubber bellow  40 , so that pushing or pulling the rubber bellow  40  has to be done against the restoring force of the spring  50 . The rubber bellow  40  and the spring  50  are situated in a housing  60 , whereby a movable press button  70  is situated in an opening on the upper side of the housing  60 . The press button  70  attaches the rubber bellow  40  on its upper side, and might also be connected therewith.  
         [0029]    The rubber bellow  40  is connected, preferably via a channel  80  that might also be part of the rubber bellow  40 , to a valve chamber  90  as a further part of the pressure generation unit  20 . The valve chamber  90  has a first valve  100  opened towards environment (i.e. outside of the fluid movement system  10 ), and a second valve  110  opened towards the fluid movement area  30 . Both valves  100  and  110  are preferably flap valves. However, it is clear that any other valve type supporting the functioning of the fluid movement system  10 , as described below, can be applied accordingly and might be selected dependent on criteria such as prize, ease of use, reliability or precision.  
         [0030]    The rubber bellow  40  in conjunction with the mechanism of the spring  50  and the valves  100  and  110  constitutes a pressure chamber, which generally allows generating and maintaining a pressure, such as overpressure or underpressure, against the environment of the fluid movement system  10 . Details will be shown and explained later.  
         [0031]    The fluid movement area  30  comprises a sensor area  120  coupled (in the example of FIG. 1: abutting) to the valve chamber  90  via the second valve  110 . The sensor area  120  is further coupled to a sample area  130  for receiving a fluid sample to be analyzed within the sensor area  120 . Sensor elements  140  are located in the sensor area  120 .  
         [0032]    For operating the fluid movement system  10 , a fluid sample is placed into (e.g. filled in) the sample area  130  and will be kept there, preferably under the influence of capillary forces or by additional valves. Because there is no initial pressure difference inside of the fluid movement system  10  with respect to its environment, capillary force might be enough to prevent the sample fluid in the sample area  130  from dropping into the fluid movement area  30  before an underpressure is applied.  
         [0033]    In the initial position of the fluid movement system  10 , as shown in FIG. 1, the rubber bellow  40  will be opened under the influence of the spring  50 . The spring  50  also presses an inner flange  75  of the press button  70  against the inner top wall of the housing  60 , thus acting as a stopper for the press button  70 . The rubber bellow  40  thus has its maximum volume in this initial position.  
         [0034]    For moving the sample fluid, located into the sample area  130 , to the sensor area  120 , the press button  70  will be pressed into the direction of arrow A, thus forcing the rubber below  40  to decrease its volume. The volume decrease of the rubber bellow  40  leads to an overpressure therein and thus into the valve chamber  90 , which, again, closes the second valve  110  and opens the first valve  100 , so that the overpressure can be released to the environment.  
         [0035]    When the force into the direction of the arrow A will be removed, the spring  50 , which has also been pressed down, will force the rubber bellow  40  to return into its initial position. This volume increase of the rubber bellow  40  driven by the spring  50  will lead to an underpressure in the rubber bellow  40  and thus into the valve chamber  90 , which closes the first valve  100  and opens the second valve  110 . This leads to an underpressure in the sensor area  120 , which again will draw fluid of the fluid sample located in the sample area  130  into the sensor area  120  to the sensor elements  140 .  
         [0036]    The volume of the rubber bellow  40  should preferably be adjusted to the volume of the sample area  130 , so that by releasing the underpressure, calibration fluid located over the sensor elements  140  can be completely removed and substituted by sample fluid. In case that e.g. a calibration fluid or gel has been situated on the sensor elements  140 , it will also be removed from the sensor elements  140  under the influence of the underpressure.  
         [0037]    [0037]FIG. 2 shows another embodiment of the fluid movement system  10  according to the invention. While the embodiment of FIG. 1 only provides one sample area  130  with sample fluid to be moved into the sensor area  120 , the fluid movement system  10  of FIG. 2 further provides a second sample area  200 . As in FIG. 1, the first sample area  130  uses an underpressure generated by the rubber bellow  40  to move fluid (contained in the first sample area  130 ) into the sensor area  120 . In contrast to FIG. 1, however, the embodiment of FIG. 2 further utilizes the overpressure, as generated by pushing down the press button onto the rubber bellow  40 , to move fluid contained to the second sample area  200  to the sensor area  120 .  
         [0038]    Other differences are that the spring  50  in the embodiment in FIG. 2 is a membrane type spring. Further, the channel  80  in FIG. 2 opens directly to the sensor area  120  thus omitting the valve chamber  90 . The first valve  100  and the second valve  110  are now located at the end of the sensor area  120 . As in FIG. 1, the first valve  100  opens or closes towards the environment outside of the fluid movement system  10 . The second valve  110  opens or closes a connection  210  of the first sample area  130  towards the sensor area  120 . The first valve  100  is situated in a way that an overpressure in the sensor area  120  will close the second valve  110  and open the first valve  100 . In the example of FIG. 2, the first valve  100  is situated in the air stream from the bellow  40  ‘behind’ the connection  210 .  
         [0039]    In operation, pushing the press button  70  into the direction of the arrow A will cause an overpressure into the rubber bellow  40  and accordingly into the sensor area  120 , so that the first valve  100  will open and the second valve  110  will close. Since an opening  220  of the second sample area  200  towards the sensor elements  140  is located in-between an airflow directed from the rubber bellow  40  over the channel  80  and the sensor area  120  to the (opened) first valve  100 , sample fluid located into the second sample area  200  will be drawn into the sensor area  120  to the sensor elements  140 , e.g. in the sense of a water jet pump. In principle, the overpressure flow around the (capillary) opening  220  of sample area  200  will suck sample fluid out of sample area  200  and into the sensor area  120  to the sensor elements  140 .  
         [0040]    When the force into the direction of the arrow A will be released, the (membrane) spring  50  will force the rubber bellow  40  to return into its initial position, thus generating an underpressure into the rubber bellow  40  and accordingly into the sensor area  120 . Under the influence of the underpressure into the sensor area  120 , the first valve  100  will close and the second valve  110  will open, thus clearing the connection of the first sample area  130  via the connection  210  into the sensor area  120 . Fluid contained into the first sample area  130  will then be drawn under the influence of the underpressure into the sensor area  120  to the sensor elements  140 . Since the sensor elements  140  are located between the connection  210  and the opening  220 , no further fluid from the second sample area  200  or the opening  220  will be directed towards the sensor elements  140 . The embodiment of FIG. 2 thus uses the underpressure as well as the overpressure as generated into the rubber bellow  40  for moving different fluid samples in the sensor area  120 .  
         [0041]    It is clear that by providing adequate conduits and/or suitably forming the parts of the fluid movement area  30 , the fluid movement into the fluid movement system  10  can be directed and controlled as required. For the sake of simplicity and also since FIGS. 1 and 2 only represent the drawings for illustrating the principles of the invention, details for guiding and controlling the fluid flow have been omitted.  
         [0042]    [0042]FIG. 3A shows another embodiment of the invention. The pressure generation units  20  of FIG. 3A and FIGS.  1  - 2  substantially correspond to each other with the difference that in FIG. 3A the chamber  90  between the rubber bellow  40  and the sensor area  120  is integrated into the housing  60 . While the first valve  100  could also have been provided e.g. at the right side wall of the housing  60 , it is situated in FIG. 3 on the left side wall of the housing  60 . This also illustrates that there are many variations possible to arrange the valve(s) without departing from the idea of the invention.  
         [0043]    While insofar the embodiment of FIG. 3A does not go beyond the principles as illustrated with respect to FIGS. 1 and 2, the pressure generation units  20  of FIG. 3 further provides means for controlling the timing for moving the fluid(s). For that purpose, the press button  70  further comprises hooks  300  at its lower end. Corresponding locking means  310  are provided at the housing  60 .  
         [0044]    In the example of FIGS.  3 , each hook  300  comprises a ball  305  situated on a rod  307  having a smaller diameter than the outer diameter of the ball  305 . Each locking means  310  comprises a spring-loaded leaf  315  with an opening  317  having a first shaping  318  allowing to receive the ball  305  and a second shaping  319  that cannot receive the ball  305 . The leaf  315  is coupled to a spring clock mechanism  320 .  
         [0045]    [0045]FIGS. 3B, 3D and  3 E depict an initial position P 0  of the locking means  310 , wherein the leaf  315  is angled towards the hook  300 . In that initial position P 0 , the ball  305  will ‘see’ the first shaping  318  of the opening  317 , and can penetrate through when lowered in direction of angle A. However, once entered through the opening  317 , the hook  300  (e.g. in combination with the flange  75  or other parts of the press button  70 ) will move the leaf  315  further towards a position P 1 . In this position P 1  (cf. FIGS.  3 CE), the rod  307  is located within the second shaping  319 .  
         [0046]    Once the pressure on the press button  70  in direction of arrow A will be removed, the spring  50  will force the press button  70  in its initial position. However, the spring clock mechanism  320 , which has been activated when forcing from position P 0  into position P 1 , will first keep the leaf  315  in the position P 1  and slowly release to return to position P 0 . In a preferred embodiment, the spring clock mechanism  320  comprises a spring together with a gear mechanism, which when wound up will slowly return into its initial position, whereby the returning speed is dependent on the gear setting. Such mechanisms are well known in the art and need not be discussed here in detail.  
         [0047]    As soon as the leaf  315  returns to position P 0 , the first shaping  318  of the opening  317  will release the ball  305  from the leaf  315 , so that the press button  70  can also return into its initial position.  
         [0048]    In other words, the shaping of the locking means  310  is provided in a way that when the hook  300  lowers towards the locking means  310 , the hook  300  will first touch the locking means  310  in a first position that will not engage the hook  300 . When the hook  300  is further moved into the direction of the arrow B, the locking means  310  will be forced under the influence of the hook  300  into a second position engaging the hook  300 , so that it cannot return into its initial position once the force in direction of arrow A will be removed. The hook  300  will be locked e.g. by the converging opening  319  into the second position. Thus, the press button  70  will be kept down into a press down position and can first return to its initial position when the locking means  310  will release the hook(s)  300 . Controlling the release of the hooks  300  will therefore allow controlling the timing of the underpressure phase when the rubber bellow  40  will return into its initial position (thus generating an underpressure). By means of an external force, e.g. bending or moving the locking means  310 , the hooks  300  can be released to initiate the underpressure. This external force can be controlled by the fluid movement system  10  itself or by a reading device.  
         [0049]    Instead as shown in FIG. 3A, the valves  100  and  110  can also be provided as depicted in FIG. 2, thus enabling to utilize the overpressure as well as the underpressure phase.  
         [0050]    FIGS.  4  illustrate another example for the interaction between the hook  300  and the locking means  310 . In this example, a conical shaping  330  (referred to as cone  330 ) replaces the ball  305 , also situated on the rod  307  having a smaller diameter than the outer diameter of the cone  330 . Each locking means  310  comprises the spring-loaded leaf  315  with the opening  317  allowing to receive the cone  330 . The leaf  315  is coupled to a spring  340 . The locking means  310  further comprises a releasing means  350  having a locker  355  coupled to a timing means  360 .  
         [0051]    In FIG. 4A, the hook  300  and the locking means  310  are in their initial position. In FIG. 4B, the hook  300  has been lowered (direction of arrow A) towards the locking means  310 , whereby the cone  330  has moved the leaf  315  into the direction of arrow until the cone  330  can enter through the opening  317 . Once the cone  330  enters through the opening  317 , the spring  340  will push the leaf  315  back into direction of arrow C, as shown in FIG. 4C. In this position, the cone  330  is locked by the leaf  315  and could not be withdrawn from the locking means  310  into the direction against arrow A.  
         [0052]    Starting from the position as shown in FIG. 4B, the cone  330  pushes down a plunger  365  via a face  366  and a rod  367 , when the cone  330  is further moved into the direction of arrow A. The plunger  365  can thus moved into a cylinder  370  against the force of a spring  375  in the cylinder  370 , until an end position is reached as shown in FIG. 4C.  
         [0053]    [0053]FIG. 4E shows the timing means  360  in greater detail. The cylinder  370  has an aperture  376  that can be opened or closed by a valve  380 . When the plunger  367  is moved into the direction of arrow A, the thus created overpressure will open the valve  380  and release air out of the cylinder  370 . When the force into the direction of arrow A is removed, the spring  375  will push the plunger  367  back against the direction of arrow A. The created underpressure in the cylinder  370  will close the valve  380 , so that this underpressure cannot be immediately released and will counteract the force of the spring  375 . In order to slowly release the underpressure, the cylinder  370  has at least one further opening  385  allowing an airflow into the cylinder  370 . By designing the seize of the opening  385 , determined e.g. by the cross section and the number of the openings  385 , the time for releasing the plunger  367  and thus the entire locking means  310  back into the position as shown in FIG. 4B can be determined.  
         [0054]    The locking means  310  when moved back into the position as shown in FIG. 4B will also push back the hook  300  as shown in FIG. 4B. In this position, the locker  355  will also open the locking of the cone  330  by the leaf  315 , so that the hook  300  can then be moved back into the position of FIG. 4A.  
         [0055]    [0055]FIG. 4D further shows parts of the locking means  310  together with the hook  300  in three dimensional view.  
         [0056]    As depicted in FIG. 5, the fluid movement system  10  might be part or integrated into a (disposable) cartridge  400  with contacts  410  to couple to a reading device  420 . The contacts  410  are coupled to the sensor elements  140 , thus allowing to connect the electrical signals of the sensor elements  140  to a reading device  420 . The reading device  420  converts electrical signals of the sensor elements  140  into concentration values, which can be output on a display  440 .  
         [0057]    Pressing down the press button  70  of the fluid movement system  10  in FIGS.  1 - 3  can be done manually, but also automatically, e.g. forced by the reading device  420 . Preferably, the press button  70  will be pressed down when the fluid movement system  10  will be connected to the reading device  420 , e.g. by inserting the fluid movement system  10 , or parts thereof into a slot  430  of the reading device  420 . In case of manual pressure, the reading device  420  might display on the display  440  a request to the user to press down the press button  70  for initiating the (calibration and) analyzing process. In case of automatic pressure application, the reading device  420  might push onto the press button  70  once the fluid movement  10  has been inserted or otherwise coupled to the reading device  20 . It is clear that this kind of automatic process can also be applied for locking the fluid movement system  10  from being prematurely removed from the reading device  420  before the measurement has been completed.