EP1510254A2 - Method and device for detecting an analyte in a fluid - Google Patents

Abstract

To determine analytes in a fluid, the fluid sample droplets (19,20) are deposited on a substrate (1) of a movement plane to be moved to the sensor site while wholly in contact with the substrate using acoustic surface waves from a transducer (7) or electro-wetting. To determine analytes in a fluid, the fluid sample droplets (19,20) are deposited on a substrate (1) of a movement plane to be moved to the sensor site while wholly in contact with the substrate using acoustic surface waves from a transducer (7) or electro-wetting. A sensor at a test zone (21) is brought into contact with the samples to determine the analytes directly or indirectly, using an ion selective electrode. The analytes are identified solely by the sensor or a reaction which is registered by the sensor. The substrate is shrouded by a cover (2), fitted with septums (11) and a lock (13) to secure it at the substrate.

Description

The application relates to a method for the determination of an analyte in a liquid and a device for determining an analyte in a liquid accordingly the inventive method.

State of the art

The analytical detection and concentration determination of certain biological and medically relevant substances from complex samples represents an important Basis of modern medical diagnostics. In recent years have been Methods and procedures developed, with smaller and smaller sample volumes achieve accurate analytical results, especially through the introduction of microanalytical Method. The increasingly used "lab-on-a-chip" systems work with liquid quantities in the micro to nanoliter range, which in these systems to a spatially defined analytical area, the location of Investigation, need to be moved. At these places then the actual takes place Determination of the analyte, mostly with specific sensors.

Conventional "lab-on-a-chip" systems generally consist of microstructured ones closed channels, which the liquid transport to the actual cause sensory elements. For the movement of liquids are mostly mechanical micropumps or electrokinetic methods used. So can Liquids in these channels, for example, by electroosmosis, hydrostatic Pressure differences, capillary forces or centrifugal forces are moved. Further Methods of transporting very small amounts of liquid are electrowetting For example, in "Electrostatic Actuation of Liquid Droplets for Microreactor Applications "(Washizu M. in IEEE Transactions of Industry Applications 34 (4): 732-737, 1998), "Creating, Transporting, Cutting, and Merging Liquid Droplets by Electrowetting Actuation for Digital Microfluidic Circuits "(Cho S.K., Moon H. Kim C.J. in Journal of Microelectromechanical Systems 12 (1): 70-80, 2003) or "Micropumping by electrowetting "(Kim C.J. in Proceedings of 2001 ASME International Mechanical Engineering Congress and Exposition, November 11-16, 2001, New York, NY) is described, and the transport of liquids on surfaces with the help of surface acoustic waves, so-called Surface Acustic Waves (SAW), as is for example in "Flatland fluidics" (Wixforth A., Scriba J. and Gauer C. in mstnews 5/02, pages 42-43).

The determination of analytes in microanalytical systems is usually carried out by means of Sensors integrated into the channels of the chips. The measuring methods of the used Sensors are based in particular on the previously used microanalytical methods on spectroscopic methods such as fluorescence or Absorption measurements, electrochemical methods, conductivity measurements, luminescence or electrochemiluminescence method and detection method by means of Optic sensors. On the other hand, biosensors have ion-selective electrodes and other sensors which are widely used in routine macroscopic diagnostics are previously proven in microanalytical systems not routinetauglich. The reasons for this are in particular the high manufacturing costs of such microstructured Sensors and electrodes as well as the hitherto unsatisfactory possibilities Move fluids through active pumping from the outside in these systems. Other microanalytical devices are in particular protein arrays and arrays for the determination of nucleic acids. Furthermore, there are sensor modules, which in clinical and / or chemical analyzers are installed. These are above all Modules for the determination of electrolytes and other analytes such as Glucose or lactate. However, these methods established in laboratories usually work with significantly larger sample volumes.

The commonly used microanalytical devices are, with the exception of arrays for protein or nucleic acid analysis, almost exclusively built up microfluidic channels. These closed channels are a few microns wide and deep, but usually very long, so the volume of these channels relative to whose cross-section is large. This can be a significant proportion in these systems the sample volume is not used to determine the analyte in the sensory areas used by the system, but represents not usable dead volume. So are a further reduction of the required sample quantity in these channel systems principle limits set. Furthermore, such channels have the great disadvantage that the surface in direct contact with the sample in relation to the Volume is very large. This results in a high probability that Components of the liquid remain on the surface of the channels and thus Contaminate samples that are moved in the same channels for later measurements can. Such systems can thus due to the aforementioned carryover problem often used only as disposables. Such microanalytical Systems also have the disadvantage that they do not leak in microchannels or mix only with great effort and possibly occurring air bubbles can easily bring the river in the canals to a standstill. This will be Such systems are relatively prone to failure and expensive to manufacture, so they cost out would have to be used several times in routine operation, but what is mentioned above Reasons (carry-over problem) is currently not feasible.

Ion-selective electrodes are currently used mainly in macroscopic analysis systems, especially in clinical and chemical electrolyte analysis modules Analysis systems, used. Such macroscopic detection systems have considerable Disadvantages. So require such modules and systems in addition to the clear larger sample volumes numerous hoses, valves and pumps that flow control the fluids within these systems. For example, have air segments be introduced into the liquid flow to the hoses and the sensors between the individual measurements and calibrations. For the controller the liquid streams are other sensors, in particular light barriers or Conductivity sensors, needed to ensure that the air segments are correctly or be discharged. Although, similar to microanalytical systems with microfluidic channels, only a relatively small volume for the actual determination The analyte needs to be in the current systems about twenty times larger volume of liquid can be used to a non-entrainment Ensure measurement. Such systems are therefore often very prone to failure and maintenance-intensive. Due to the construction described above, it is not possible, handy and mobile devices to build, which ideally for the medical laboratory or a near-patient diagnostics could be used. Another disadvantage of the above Devices are the high production costs because all systems and modules come from many different components must be assembled. In contrast to Macroscopic analysis systems are available for microanalytical methods and devices So far, no ion-selective electrodes that are like their macroscopic Routine analogues are suitable for multiple measurements.

A special case of microanalytical systems are the microarrays Microarrays are understood as analytical systems which on a carrier many have sensory elements, usually arranged at regular intervals, so that these used for many simultaneously or temporally offset expiring provisions can be. In particular, microarrays are used to analyze proteins and nucleic acids used. Such arrays are difficult to regenerate, so that Such systems, for the reasons described above also not for a multiple Use are suitable.

Some microarrays for protein determination work with planar surfaces. These Arrays, however, require relatively large volumes. So must in such systems For example, incubate with about 50 microliters of sample liquid to bind allow the analyte with the detection molecules. To a depletion of To prevent analytes, the sample must be mixed, which is a large represents technical problem.

These arrays are all for single use. You usually set flat Large-volume arrays involving mixing during incubations also represents a technical challenge. The actual proof of Analytes are mostly made by optical methods, with expensive and complex optical Detection systems are needed, so this detection method only in a few technically equipped special laboratories can be performed.

To solve these technical problems have been methods and devices which describes a transport of liquids, especially in microanalytical Systems, can effect.

German patent application DE 10117771 A1 describes methods and devices for the manipulation of small quantities of liquid by means of surface acoustic waves. The object of this patent application described in the published patent application is to locate liquids on a solid state chip and, where appropriate to mix. For this purpose, devices and methods are described, which liquids by means of surface acoustic waves on a flat substrate to move to so-called functionalized areas. In such functionalized For example, a chemical or biological reaction may take place in areas. DE 10117771 A1 describes for this purpose devices in which at certain Make functionalized directly in / on the surface of the solid-state chip Areas are used which, among other things, used as sensors in analytical procedures can be. The functionalized areas for analyzing the liquid are integrated directly into the substrate of the solid-state chip, on which the transport the liquid takes place, i. the relevant devices for liquid transport and the devices relevant to the determination of the analyte in the fluid are combined in a single plane, the transport plane. The However, production and also the cleaning of such multifunctional surfaces is only possible with great financial and technical effort, so that such systems be used neither as a disposable article nor in routine analysis. Farther The sensors integrated into the surface of the carrier chip introduce inhomogeneities the surface of the carrier substrate, for example by different surface wetting properties or spatial elevations or depressions. As a result, a uniform transport of liquids over the Surface of the carrier substrate severely restricted, so that complex controls and / or additional forces are needed to compensate for these inhomogeneities and to allow a smooth and effective transport of the liquid. Farther describes DE 10117771 A1 arrangements in which two solid surfaces face each other and between which the liquid to be examined is located and in contact with both surfaces. Here, the devices for the Generation of surface acoustic waves and the functionalized areas the two different surfaces are located. However, also finds in such Arrangements of transport of the liquid on the substrate of the transport plane not regardless of the functionalized areas, since the liquid volume is always is in contact with both surfaces. In such arrangements occur additional Interactions, in particular surface effects, interface effects and capillary effects, between the liquid and the two surfaces contacted so that Such arrangements are usually not for the transport of liquids over the Substrate are suitable, but are mainly used for mixing a liquid can.

The object of the present invention is to overcome the disadvantages of the prior art remove. In particular, it is an object of the present invention to provide microanalytical To provide methods and devices that meet the needs of a cost-effective and user-friendly routine analytics and which become one multiple reuse.

Inventive solution

The inventive solution of the disadvantages described in the prior art microanalytical methods and devices and subject of the invention are methods and devices for the determination of analytes in liquids, the characterized in that the liquid to be examined on a substrate is applied and the liquid volume to be examined on the flat surface of the substrate, the so-called transport plane, at the location of the investigation is moved, the liquid during transport exclusively with the Substrate of the transport plane is in contact. The movement can be done in particular by Procedures such as surface acoustic waves or Elektrowetting be effected. Furthermore, the methods and devices according to the invention are characterized in that that they have at least one sensory element and optionally further analytical Have units which are separated from the substrate of the transport plane in one second plane opposite the substrate, the so-called detection level, are located. This detection level is designed such that the liquid volumes during their movement to the place of investigation or away from there with the Be in contact or disturbed by it in their movement. Thus, with the inventive methods and apparatuses a uniform and undisturbed movement of the liquid volume at the transport level be guaranteed. The evidence level indicates where the location of the Investigation reveals special formations or devices which only on This defined location of the investigation, a contact with the examined Make liquid and thus allow determination of analytes in the liquid. This contact surface may in particular be formed such that it has a Permanent reduction of the distance of the sensory element or the Has evidence of the transport level at the locations of the investigation, or that the sensory element or the detection plane is designed to be movable is, so that the sensory element then temporarily with the liquid volume to be examined can be contacted if this is at the site of the investigation located.

Furthermore, the transport level and the proof level can become a device be connected, which can be placed in an external device. The external device can in particular to control the movements of the liquid volumes to be examined serve, electrical and / or fluidic contacts to the invention Produce device and is possibly able to part of the analytical Unit.

A preferred embodiment consists of a closed device, which the Substrate of the transport plane includes as a bottom surface and a lid, which preferably Having side walls, so that a closed device are constructed can. The lid may further have openings for liquid application, which with a cover, in particular a pierceable septum, are closed. In the Cover of the housing is integrated at least one sensory element. The lid corresponds thus in most cases the detection level of the device. The sensory Element can hereby directly on the site of the investigation in / on the transport plane facing Surface of the lid integrated / applied.

In other embodiments, the movably formed sensory element on Place of examination for the determination of the analyte for a short time from a transport position moved to a measuring position. The transport position corresponds to a spatial position of sensory element in which it is not in contact with the liquid volume, so that the transport of the liquid volume over the transport plane not from the sensory Element is affected. The measuring position corresponds to a spatial position of the sensory element, in which the distance to the transport plane compared to the transport position is reduced and the sensory element in contact with the fluid volume so that the determination of the analyte by means of the sensory element can be carried out. The substrate of the transport plane may further devices to generate a movement of the liquid volumes to be examined, in particular interdigital electrodes for generating surface acoustic waves or Electrodes as used in electrowetting processes. The Devices which generate the forces required for fluid movement, however, in the case of transportation by surface acoustic waves, they do not necessarily have to be mounted directly on the substrate of the transport plane, but it is also possible the devices for generating these forces are located outside the substrate, for example, as part of an external drive device. In this case will be the externally generated forces then coupled into the transport plane, for example by means of electric fields or mechanical vibrations. This is particularly advantageous if disposable devices are to be used, because then on expensive devices to dispense with generating a movement on the transport plane itself can, which causes a significant production cost reduction.

The subdivision of the devices according to the invention in a plane, which of the movement the liquid volume to be examined (transport plane), and a plane, which serves for the analytical examination of the liquid volumes (detection level), allows on the one hand an undisturbed movement of the liquid volumes on the substrate of the Transport level and, on the other hand, the production of these two levels into two distinct Processes. These two manufacturing processes do not have to be compatible. So For example, the transport level can be created independently of the verification level become. Only in the final assembly, these two are critical in each case in the production Elements brought together, preferably in the form of a closed device. Through openings in the housing, different volumes of liquid to be examined, but also calibration solutions, reference solutions, rinsing or cleaning solutions, Solutions with standardized analyte concentrations, so-called standards, or reagents, be applied to the transport plane, for example by means of pipetting or Injection. Furthermore, the liquid volumes can also be coupled by means of fluidic Systems, such as capillaries and dispensers, applied to the transport plane become. By appropriate control of the devices which the Movement of the liquid volumes generate necessary forces, one is able to the liquid volumes at any predefined location on the substrate of the transport plane, especially to the location of the investigation, to transport.

The device according to the invention additionally has in a preferred embodiment a waste container, which is connected via a panel with the device and thus belongs to the closed area of the device. The fluids passing through The panel can be transported in the waste container, by this of Transportund Detection level can be separated, allowing a return to the sensory area and thus an impairment of subsequent measurements is avoided.

When determining analytes in liquids often become very small measuring signals generated, which can be easily distorted by surrounding influences and disturbances. Therefore, in advantageous embodiments of the invention are the sensory Areas or the entire device against such external interference shielded, preferably by means of a Faraday cage, to remove the signals from interfering electrical influences to keep free or by means of a radiation-reducing envelope, to keep away direct light or stray light from optical detectors.

Analytes containing a method according to the invention or the corresponding Devices can be determined are all within the meaning of the present application Particles of interest in analytics, especially in clinical diagnostics. In particular, the term "analytes" includes atoms, ions, molecules and macromolecules, in particular biological macromolecules such as nucleic acids, peptides and proteins, lipids, Metabolites, cells and cell fragments. The analytes can be both free and on Particles, in particular artificially produced particles such as so-called "beads", bound.

For the purposes of the present application, liquids can be pure liquids and homogeneous or heterogeneous mixtures such as dispersions, emulsions or Be suspensions. In particular, in the liquids atoms, ions, molecules and Macromolecules, in particular biological macromolecules such as nucleic acids, peptides and Proteins, lipids, metabolites or biological cells or cell fragments may be included. Preferred biological fluids of interest are blood, plasma, serum, Urine, cerebrospinal fluid, tear fluid, cell suspensions, cell supernatants, Cell extracts, tissue digestions or the like. Liquids can also be calibration solutions, Reference solutions, rinsing or cleaning solutions, reagent solutions or Solutions with standardized analyte concentrations, so-called standards. liquid volumes For the purposes of the present application, in principle, any form and However, they are preferably in the form of round or flattened drops Volumes in the range of 100 nl to 10 ul before. In particular, liquid volumes are also in elongated form possible, the multiple juxtaposed sensory elements can cover.

Sensory elements in the sense of the present application are all systems for determination of analytes containing analyte-specific chemical, biochemical, biological or physical Determine sizes and their changes. The term sensory Element is not in the context of the present application to a purely technical definition of a sensor, but is fully applicable to all systems, which can enable the detection of an analyte in a direct or indirect manner.

Thus, in particular, specific binding partners of the analyte, in particular labeled Binding partner, which allows the detection of the analyte through a specific interaction enable with it (e.g., antibodies, nucleic acids with complementary Sequences, complexing agents) or specific reaction partners of the analyte, which with this one specific reaction and so by means of evidence of the corresponding Reaction products or -ucts indirectly to determine the analyte (e.g. Substrates, enzymes), as sensory elements. These sensory elements are located According to the invention, at the site of the examination, preferably in immobilized form and allow the specific detection of the analyte there. It is also possible that There, the reagents required for the determination of the analyte in dry chemical Form bound present. It should be noted that the physical location of the evidence by means of a physical or chemical sensor not necessarily with the sensory Elements at the site of the investigation, especially indirect ones Detection methods. Thus, the detection of peptidic analytes by fluorescence-labeled Antibody the detection of the resulting fluorescence radiation by an optical sensor, which in a suitable embodiment of the invention also outside may lie the actual device according to the invention, while the proof of Analytes by the antibodies as sensory elements only at the site of the investigation takes place. However, sensor elements can also be conventional sensors, in particular electrochemical sensors, biosensors, optical sensors such as absorption or Fluorescence detectors and immunological sensors such as optodes, waveguide sensors and evanescent field laser spectrometry sensors. Furthermore, sensors are included, which can determine physical quantities, such as sensors, which determine the viscosity, the density or the mass of a liquid. This is included Reactions that exhibit these properties in the course of an analyte-specific reaction the fluid changes, especially of interest. Examples are coagulation reactions or methods which allow the attachment of analyte molecules by means of them detected, called mass change.

Sensors can be present in all possible geometric embodiments, in particular as pointed sensors, as area sensors or as thick-film sensors. Especially preferred are pointed sensors, as in the case of moving away the sensor only one minimal residual volume of the liquid to be examined adheres to this and thus Carryover artifacts can be largely avoided.

In the case of analytes directly in the fluid volume to be examined with sensory Elements can be determined, moving the liquid volume according to the invention to the place of the investigation. This can preferably be done by that one first generates individual volumes of liquid and these volumes of liquid to Location of the investigation moves. This method is particularly suitable for multiple measurements and a mission in routine operation. In this case, several will be examined Liquid volumes successively to the respective location of the investigation emotional. Once a single determination has been completed, the liquid volume already investigated becomes Moved away from the site of the investigation and may for further investigation Be available or collected in a waste container. At the freed Place of investigation can now be moved to another volume of liquid, the Wegtransport of the already examined fluid volume and the forward transport of the be carried out at the same time or in succession can. Corresponding process steps can also be carried out with calibration solutions, Reference solutions, rinsing or cleaning solutions, reagent solutions or solutions with standardized analyte concentrations are carried out.

In the case of analytes that are not directly in the liquid to be examined with sensors can be determined, you often need additional reagents to the analytes to be able to determine.

Such methods are characterized in particular by the fact that the determination of the Analytes indirectly by the detection of a specific interaction with a binding partner, in particular a labeled binding partner in the form of immunoassays or detection methods using polymerase chain reactions, or a specific Reaction of the analyte with detection reagents, in particular in the form of chemical or enzymatic reactions, or a specific change in a physical or chemical size, in particular the viscosity occurs. For the determination of the analyte For example, you bring a volume of the liquid to be examined and a volume the reagent solution in contact by these volumes of liquid, for example by suitably controlled acoustic surface acoustic waves, to move towards each other, so that they eventually merge into a common fluid volume. Especially It is advantageous if the combined liquid volumes are subsequently mixed To ensure a rapid and complete reaction of the analyte with the reagents and thus to allow the most accurate determination of the analyte. to Blending can in particular suitably controlled surface acoustic waves be used. The contacting and mixing of the liquid volumes can be done directly at the site of the investigation or previously in another area of the Device, so that in the latter case, possibly after a certain reaction time, this mixture is moved to the site of the investigation.

Reagent solutions required for determination of the analyte as well as calibration solutions, Reference solutions, rinsing or cleaning solutions or standardized solutions Analyte concentrations may be introduced through special openings in the device especially through an already existing sample application septum or through a specially designed septum. The above-described application of the solutions does not necessarily have to be done by pipetting or injection through a septum, but rather In other embodiments of the invention, liquids may be contained in containers be kept ready inside or outside the housing, which at given times for example, with the help of a microdispenser or piezodispenser in the Housing brought or released there. This has the advantage that all liquids, which are needed for the determination of the analyte already present in a device may be and only the liquid to be examined has to be supplied. Especially may involve applying additional reagent solutions via one on the lid the container attached to the container, by means of a dispenser with the chamber connected is.

The liquid volumes are preferably in the form of round or flattened drops before, but there are also volumes in elongated form possible, the several side by side lying sensory elements can cover. This embodiment can then be used particularly well if several sensory elements simultaneously with the need to be in contact with the liquid volume to be examined, as for example in the electrochemical measurement of electrolytes is necessary. For this one uses in the general one or more measuring electrodes and a reference electrode with a reference electrolyte. Moving a volume of liquid to be examined and a Volume of a reference electrolyte solution toward each other and brings them into contact, it takes place the mixing of the two volumes of liquid without additional mixing Forces initially purely diffusive and thus very slow. This is particularly advantageous because at this time, immediately after contacting the liquid volumes, the two Partial volumes are located in an electrically conductive connection without interfering effectively mix thoroughly. Preferably, the liquid volume is the one to be examined Liquid in contact with one or more measuring electrodes and the reference electrolyte containing liquid volume in contact with the reference electrode, so that after the transient oscillation of the measurement signals can be an exact determination of the analyte.

The device according to the invention is preferably installed in a closed housing, which is suitable for multiple use. By this closed Design becomes an evaporation of liquids and thus a falsification of the concentration prevents the analyte. Furthermore, in a preferred embodiment a Waste container into which already examined liquids as well as reagent solutions, Calibration solutions, reference solutions, rinsing or cleaning solutions and solutions with standardized analyte concentrations are transported after their use. Of the Waste containers may in particular be designed so that these already used liquids can no longer get to the places of investigation and / or other analyte determinations can falsify. This can be done for example by a mechanical Aperture can be achieved. Furthermore, the already used samples can be adsorbed, for example by means of a fleece or sponge. This ensures that the Humidity kept constant high in the device according to the invention and so the Evaporation of small volumes of liquid is prevented without subsequent Determinations of analytes are influenced by previous provisions.

In a further embodiment, the devices or parts according to the invention are the devices are designed in such a way that the devices or parts of the devices, In particular, sensory elements are provided for a single use. This embodiment is particularly suitable for the determination of analytes in which Carryover problems can occur.

Furthermore, the present invention includes embodiments which are modular Modular system for simple as well as multiple and multiple determinations of Analytes in liquids are suitable. Particularly advantageous for these embodiments it is that the transport level and the evidence level with different materials and methods can be produced and only to carry out the determination of Analytes must be merged. Furthermore, transport level and Detection level not be directly connected to each other, for example by spacers or a common housing, but can initially independently present and only for the actual determination of the analyte in common contact be brought to the liquid volume to be examined. In particular, embodiments are advantageous in which the substrate of the transport plane as a multipurpose usable Substrate is used, which is the transport of many liquid volumes to the corresponding locations of the investigation causes, and the evidence level for a one-time Use is provided, especially in sensory elements, which are not on are based on reversible reactions and thus can only be used once. Examples of this are optical detection based glucose sensors or sensors which based on immunological methods or DNA hybridization. Here is the proof level be designed so that it contains only one sensory element and to each Determination is exchanged while the transport plane to move many volumes of liquid can be used for many analyte determinations. The evidence level but can also be designed so that it contains several sensory elements, which each can be used only once and which are different from each other separate locations of the determination, so that for each analyte determination another sensory element is used. This embodiment has the advantage that with it several analyte determinations with only once usable sensory elements can be performed sequentially in the same device.

In a further embodiment, the device according to the invention is configured in such a way, in that methods are used for the determination of analytes in liquids, which include one or more dry chemical steps. An example of this is the reflectometric glucose determination on test strips. Dry chemical processes are methods which contain at least one reagent in dry form. This must be ensured that the lowest possible humidity prevails in the device. This can be achieved in particular by the fact that in the device or in it in Connecting components such as a waste container, a moisture and / or liquid-absorbing agent such as silica gel, wherein the moisture and / or liquid-absorbing agent through a membrane or a Fleece can be wrapped. This makes it capable of even moisture-sensitive reagents to use for the determination of analytes in liquids. Such in dry Form present reagents can be used in particular in the form of a spot spot Provision or, in the case of indirect participation in the determination of the Analytes may be fixed to other locations of the device. Should such devices, which work with dry chemical reagents, used for several determinations For example, multiple spots may be at different locations in the device be attached, which independently with different to be examined Liquid volumes can be brought into contact. That is how you are in the Able to accommodate dry chemical reagents even in reusable devices, without the dry chemical reagents for further determinations damaged by the liquid volumes used in the preceding determinations become. Here, various embodiments are included. So, for example a job site be provided on which several to be examined liquid samples be applied, and several spatially separated locations of the Investigation, which all apply the same detection method, so that at the different Places of investigation Analyte determinations carried out in an identical manner become. This is particularly advantageous when multiple devices on one device identical analyte determinations are to be carried out in succession. In another Embodiment, multiple job locations and multiple locations of investigation, which all use the same detection method should be included. This is especially true advantageous if on a device several identical analyte determinations simultaneously to be carried out. In another embodiment, a job site and several locations of the investigation, demonstrating the different Analytes allow to be included. This is especially advantageous when from a Sample several different analytes should be determined. This is the sample preferably first divided into several liquid segments, which then subsequently can be transported to the different locations of the investigation. In a In another embodiment, multiple order locations and multiple locations may also be used Investigation, which allow the detection of different analytes included be.

The contact of the sensory element or the detection level to investigating fluid volume is carried out according to the invention only at the site of the investigation. The evidence level may be shaped in this area to be a permanent one Reducing the distance of the sensory element from the transport plane at Has the place of examination, or that the sensory element or the Detection level is designed to be movable, so that the sensory element only with the liquid volume to be examined is brought into contact, if this on Place of investigation is located. For this purpose, in particular the following solutions are possible.

The device may be formed such that the distance between the detection plane and transport level at the site of the investigation is permanently reduced, preferably in that the sensory elements from the actual detection plane in the direction protrude the transport plane. In particular, the distance between the verification level and transport plane outside the sensory area greater than the vertical extent the volumes of liquid, within the sensory area, i. at the place of Examination, smaller or equal to the vertical extent of the liquid volumes. This is a movement of the liquid volumes outside the sensory areas possible, which is not influenced by the sensory elements or the detection level becomes. An interaction of the liquid volumes with the sensory elements occurs on the other hand, only at the constrictions in the places of investigation. Here the actual determination of the analytes takes place, whereby the respective liquid volume preferably does not change its position during the determination. This can be, for example be effected in that during the determination of the analyte, the devices for generating the forces that cause the movement of the liquid volumes turned off become. After completion of the determination of the analyte forces can now be applied again which move the volumes of liquid away from the sites of investigation, For example, in a waste container or to another location of the investigation, the movement after leaving the examination again exclusively in contact with the transport level takes place. Advantageous in the context of this embodiment is that such permanent narrowing of the distance between the verification level and the transport level without additional technical effort and thus cost by suitable topologies the detection and / or transport level can be generated. Such topologies can Peaks, elevations, ramps and the like.

The device may further be formed such that the distance between the sensory element or the detection level and the transport level locally the examination can be temporarily reduced. For this is the sensory Element or the detection level first during the movement of the liquid volumes above the transport plane at a distance from this, greater than the vertical one Expansion of the liquid volumes is. This corresponds to the previously described Transport position. This is one not from the sensory elements or the evidence level influenced movement of fluid volumes to the site of the investigation is possible. If the fluid volume to be examined is at the site of the examination, the movement of the liquid volume is stopped and by suitable procedures the distance of the sensory element or the detection plane to shortening of the liquid volume so shortened that it is for direct contact between liquid volume and sensory element comes. In particular, you can in this case, to reduce the distance, the detection level and the transport level temporarily be moved toward each other, for example by means of an electric drive. In In other embodiments, not the whole level of evidence is at the transport level moved, but only the sensory areas, for example, by movably mounted Sensor electrodes for determining the analyte by external drives be brought into contact with the liquid volume to be examined. This matches with the previously described measuring position. After the determination of the analyte, the Detection level or the sensory element again from the liquid volume moved into the transport position and forces are applied, which the liquid volume Move away from the places of investigation, for example, in a waste container or to another place of investigation, with the movement after leaving the investigation, in turn, takes place exclusively in contact with the transport level.

The methods and devices of the invention may further be used for determination of analytes by measuring physical and physico-chemical parameters be used. For example, they can be used to determine global coagulation parameters used as the prothrombin time or the activated partial thromboplastin time become. This measurement can on the one hand via electrochemical reactions with the corresponding electrochemical sensors, as described for example in US Pat US 6,352,630 are described. On the other hand, the determination can also be made via a viscosity measurement respectively. This can, in addition to the known methods, such as optical Method or method with magnetic particles, in particular with sensors which are based on surface acoustic waves. The device can be used several times, if after reaching the necessary measurement signal, the device is regenerated, preferably with the aid of reagents known to those skilled in the art, which prevent the formation of complete coagulation. These reagents can in liquid form also with the inventive methods and devices at the transport level, in particular by means of surface acoustic waves, to the reaction mixture be transported and transported after mixing with this in a waste container become.

The methods and devices according to the invention can furthermore be carried out homogeneous or heterogeneous immunoassays can be used. For homogeneous Immunoassays, the reaction in particular on the measurement of turbidity or the optical density by means of optical sensors. Furthermore, the sensor as Waveguide be formed, in particular in the case of a measurement of the reaction means Evanescent field laser spectrometric method. In heterogeneous immunoassays can In particular, specific antibodies are used which, for example, to magnetic Particles are bound. The assays are then in a manner known to those skilled in the art Manner performed.

The device can furthermore be designed in such a way that analyte-specific detection reactions carried out with one or more separation steps or washing steps can be. For this purpose, one or more substances to be separated with a specific label or probe, for example by binding to magnetic particles or labeled antibodies. The case necessary separation of the substances, for example of bound and unbound analyte in a so-called Bound-free separation, in particular, takes place in the case of a magnetic marking in that at a certain location of the device from outside a magnetic field is applied, which the magnetic particles with the substances bound thereto holds and thus allows a washing of the particles or a media change. These Reagents and media may also be in liquid form at the transport level, in particular by means of surface acoustic waves. In particular, you can They first transported to the place of bound-free separation and after done Wash steps are fed either at the same place or another location of the measurement become. The measurement can there with the known sensors (fluorescence sensors, luminescence sensors or others). This allows in particular the Perform a complete immunoassay in a single closed device. The device can be used several times if, after reaching the necessary Measuring signal cleaned the device analogously to the above method or regenerated. The spent reagents can be placed in a waste container be transferred.

The methods and devices according to the invention can furthermore be used in methods for Determination of analytes which are based on biological or chemical Reproduction reactions are based. For genetic engineering or DNA comparisons Of living things are often only traces of cellular material available, which is why For determining these molecules methods are needed which nucleic acids in vitro reproduce in sufficient quantities. Here is in particular the polymerase chain reaction (Polymerase chain reaction, PCR), with the DNA fragments from can reproduce tiny traces of the starting material as often as desired and in a short time. One cycle of a PCR consists of three discrete temperature steps: 1. Denaturation: When heated to about 95 ° C, the DNA to be amplified melts and gives single strands. 2. Annealing: By rapid cooling to about 55 ° C, the reassociation of the single strands prevented and the primer (2 different oligonucleotides with gegensinniger Orientation) attach to corresponding complementary strand sections of the DNA. Third Extension: The DNA polymerase prolongs the strand at about 72 ° C starting from primer and thus completes the single strand to the double strand by the incorporation of nucleotides. These new molecules will serve as a template in the next cycle. It comes to an exponential multiplication of the starting DNA and in several, usually 20 to 50, Cycles, the material is often copied identically.

The devices according to the invention can be designed in such a way that they are suitable for Performing such a PCR test are suitable. In particular, the implementation of the Temperature control can be implemented in the device in various ways. The device is particularly suitable because of its microscopic size, volumes in the micro and nanoliter range to adjust to the desired temperature in the shortest possible time, which shortens the cycle times of the duplication steps. With such small volumes of liquid In particular, it is necessary to have the present liquid reaction mixtures to prevent evaporation. Various measures are suitable for this purpose. Especially can the aqueous phase (the actual PCR reaction mixture) with a with this aqueous phase immiscible medium, which has a higher boiling point than water has, for example mineral oil, are overcoated. In other embodiments be achieved by a suitable choice of the internal volume of the device, that quickly builds up a corresponding vapor pressure, which further evaporation of the Reaction solution prevents, especially if the volume surrounding the liquid is very small. In other embodiments, this can be achieved by the Reaction is carried out at very high humidity or vapor saturation. The cyclical Controlling and adjusting the temperature of the reaction mixture can be different Species take place. In particular, the entire device or certain parts of the device, which contain the reaction mixture, are heated or cooled from the outside. In this case, the devices according to the invention make very rapid temperature changes achieved, since preferably the volume of the liquid to be tempered very can be small and the device can be made of materials which are very high Have thermal conductivity. In further embodiments of the invention are in the device different temperature zones contain, wherein the temperature generation and regulation can be achieved by methods known in the art. Especially Heating or cooling elements may be installed in the detection level. These will externally driven such that the required for the PCR amplification various Temperatures at different locations of the device permanently or temporarily are set. These set to a certain temperature ranges or the heating elements apply in the sense of the invention as places of investigation or sensory elements, because only in these places by the tempering elements the specific amplification reaction may take place to detect the analyte. Thus, the heating elements or the detection level in all before be executed described embodiments. Particular preference is given here to embodiments, in which the different temperature zones by reductions the distance between the transport plane and the lid are defined, wherein the Heating elements located at these locations at a reduced distance and the reaction mixture at these points in direct contact with the lid or to be there located heating elements is located. With the help of the transport plane can now be carried out DNA amplification, the reaction mixture to the respective preheated Areas are moved in the device. The heat dissipation is preferably carried out on the lid side by direct liquid contact with additional mixing of the reaction mixture for example, by surface acoustic waves or by electrowetting, but also embodiments are conceivable without additional mixing the reaction mixture or with non-direct heat transfer or with lateral or bottom-side heat supply work. Detection of analytes using PCR methods can be done in different ways. In particular, this can be performed by so-called "real time PCR" method in a person skilled in the known manner with the measurement of fluorescence used in these methods Choice of a material that is as transparent as possible, either from the side of the transport plane or the side of the evidence level. Furthermore, a so-called End-point PCR can be carried out in a manner known to the skilled worker, in the end the reaction, the product is moved in a detection area, where the corresponding Nucleic acid sequences are present there as specific template probes have been immobilized. This area can advantageously also be tempered, to ensure a specific hybridization. The detection then takes place with known in the art, wherein in general any known post-PCR detection method suitable.

The invention will be more apparent from the exemplary figures described below explained.

1

Substrat der Transportebene

2

Deckel

3

elastischer Bereich des Deckels

4

Abfallbehälter

5

Saugvlies

6

Abfalltropfen

7

Transducer-Elemente

8

Magnet

9

Heizelement

10

Lüfter

11

Septum

12

Elektrischer Kontakt der Transducer-Elemente

13

Verschluss

14

Ionenselektive Elektrode

15

Referenzelektrode

16

Blende

17

Elektrischer Kontakt der ionenselektiven Elektrode

18

bevorzugte Bewegungsbahnen

19

zu untersuchende Flüssigkeitsprobe

20

Referenzelektrolytlösung

21

Ort der Untersuchung

22

Reagenzbehälter

23

Elektrischer Kontakt der Referenzelektrode

24

Dosiereinrichtung

25

Düse

26

Welle

27

Anregungslicht

28

Fluoreszenzlicht

29

Schrittmotor

30

Sensorische Elektroden zur Viskositätsbestimmung

Figur 1 zeigt eine Aufsicht auf eine Ausführungsform einer erfindungsgemäßen Vorrichtung, welche zur Bestimmung von Analyten, beispielsweise Ionen, mit Hilfe von integrierten ionenselektiven Elektroden geeignet ist.

Figur 2 zeigt eine Schnittansicht der Vorrichtung aus Figur 1 entlang der dort gezeigten Linie A-A.

Figur 3 zeigt eine Explosionszeichnung einer Vorrichtung entsprechend Figuren 1 und 2.

Figur 4 zeigt eine erweitere Ausführungsform einer erfindungsgemäßen Vorrichtung, wie sie in Figur 1 und 2 dargestellt ist.

Figur 5 zeigt eine Schnittansicht einer Ausführungsform einer erfindungsgemäßen Vorrichtung, welche zur Bestimmung von Analyten, beispielsweise Ionen, mit Hilfe von Dickschichtelektroden (thick film electrodes) geeignet ist.

Figur 6 zeigt eine Schnittansicht einer Ausführungsform einer erfindungsgemäßen Vorrichtung, welche zur Durchführung von PCR-Reaktionen, insbesondere zur Bestimmung von Analyten mittels real time-PCR, geeignet ist.

Figur 7 zeigt eine erweiterte Ausführungsform einer erfindungsgemäßen Vorrichtung am Beispiel einer Erweiterung von Figur 6, mit welcher die Durchführung von Waschschritten in einer geschlossenen Vorrichtung möglich ist.

Figur 8 zeigt eine Aufsicht auf eine Ausführungsform einer erfindungsgemäßen Vorrichtung, welche zur Bestimmung von Analyten mittels einer Viskositätsmessung geeignet ist.

The reference numerals in the figures mean:

1

Substrate of the transport plane

2

cover

3

elastic region of the lid

4

waste container

5

breather

6

waste drop

7

Transducer elements

8th

magnet

9

heating element

10

Fan

11

septum

12

Electrical contact of the transducer elements

13

shutter

14

Ion-selective electrode

15

reference electrode

16

cover

17

Electrical contact of the ion-selective electrode

18

preferred trajectories

19

fluid sample to be examined

20

Reference electrolyte solution

21

Place of investigation

22

reagent

23

Electrical contact of the reference electrode

24

metering

25

jet

26

wave

27

excitation light

28

fluorescent light

29

stepper motor

30

Sensory electrodes for viscosity determination

FIG. 1 shows a plan view of an embodiment of a device according to the invention which is suitable for the determination of analytes, for example ions, with the aid of integrated ion-selective electrodes.

FIG. 2 shows a sectional view of the device from FIG. 1 along the line AA shown there.

FIG. 3 shows an exploded view of a device according to FIGS. 1 and 2.

FIG. 4 shows an expanded embodiment of a device according to the invention, as shown in FIGS. 1 and 2.

Figure 5 shows a sectional view of an embodiment of a device according to the invention which is suitable for the determination of analytes, for example ions, with the aid of thick-film electrodes.

FIG. 6 shows a sectional view of an embodiment of a device according to the invention which is suitable for carrying out PCR reactions, in particular for the determination of analytes by means of real-time PCR.

FIG. 7 shows an expanded embodiment of a device according to the invention, using the example of an extension of FIG. 6, with which it is possible to carry out washing steps in a closed device.

Figure 8 shows a plan view of an embodiment of a device according to the invention, which is suitable for the determination of analytes by means of a viscosity measurement.

Description of the figures

FIG. 1:

Figure 1 shows a plan view of an embodiment of an inventive Device which for determining analytes, for example ions, with Help of integrated ion-selective electrodes is suitable. The transport level is realized by a planar substrate (1). In the illustrated embodiment becomes the liquid transport by surface acoustic waves causes. For this purpose, in the edge regions of the substrate (1) a plurality of interdigital Transducer elements (7) arranged on a piezoelectric element, which be controlled by the associated electrical contacts (12) and the generate necessary surface acoustic waves for transport. Farther The device includes a lid (2), which in a certain Distance from the substrate (1) is located and at the site of the investigation (21) the sensory Elements, in this example three ion-selective electrodes (14) and the reference electrode (15), and thus corresponds to the detection level. The distance between the two levels is in the present case through the closures (13). The liquid volumes (in the present example the to be examined Liquid sample (19) and a reference electrolyte solution (20)) can after being discharged through one of the septa (11) to the place of examination (21) are moved. The location of the investigation is in the present case designed such that in this area the distance between the substrate (1) the transport plane and the cover (2) by a local lowering of the Cover is reduced. At the place of the investigation, the one to be examined thus arrives Liquid (19) or the reference solution (20) with ion-selective electrodes (14) and the reference electrode (15) in contact. The signals of the electrodes will be by means of the associated electrical contacts (17) and (23) of an evaluation unit fed. After determining the potentials between the ion-selective ones Electrodes (14) and the reference electrode (15) are now the combined liquid volumes (19) and (20) by means of surface acoustic waves in the waste container (4) moves, which in the present case with a Saugvlies (5) for Fluid intake is equipped and by a diaphragm (16) from the transport plane is disconnected. To illustrate the movement paths of the liquid volumes are preferred trajectories (18) shown.

FIG. 2:

Figure 2 shows a sectional view of the device of Figure 1 along there shown line A-A. The liquid sample (19) to be examined is replaced by a Septum (11) on the substrate (1) given the transport plane. By means of Transducer elements (7) generated surface acoustic waves is the zu investigating liquid moves to the location of the examination (21), which is by a lowering of the lid (2) in the direction of the substrate (1) of the transport plane distinguished. There are three ion selective in the present example Attached electrodes (14) as sensory elements, which are used to produce a direct contact with the liquid to be examined additionally from the lid (2) protrude. The reference electrolyte solution (20) is in the same way by a another septum placed on the substrate of the transport plane and under the reference electrode (15) moves. Both liquid volumes (19) and (20) come on Place of investigation in contact and are thus conductively connected without it first comes to a thorough mixing. After the measurement is the Unified liquid volume through a diaphragm (16) into a waste container (4) moved and there received in the form of a waste droplet (6) by a Saugvlies (5).

FIG. 3:

FIG. 3 shows an exploded view of a device according to FIG. 1 and 2. For better illustration, in this drawing, the substrate (1) of Transport plane separated from the lid (2). For reasons of clarity are the electrodes integrated in the cover at the place of examination (21) and the associated interconnects and contacts are not shown. In this figure is clear to see that the substrate (1) represents the transport plane on which the Fluid volumes are moved and which the transducer elements (7) containing the forces for transporting the liquid volumes (19) and (20) produce. Functionally separated from the lid (2) which is the sensory Contains elements at the site of the study (21). The two functionally different Parts (1) and (2) of the device are replaced by closures (13) connected with each other. These closures ensure that the substrate of the Transport level and the lid are functionally separated from each other, i. yourself in are at a distance from each other in which they are not relevant in their influence each other's functions. In particular, the distance outside the location of the investigation so large that the liquid volumes only are in contact with the substrate of the transport plane and on this unaffected by the sensory elements in the lid. on the other hand The fluid volumes are located at the locations of the study the sensory elements in close contact without any transport it is asked for. This contact can be permanent as well as temporary Reductions in the distance between the lid or the sensory elements be evoked at the site of the investigation.

FIG. 4:

FIG. 4 shows an expanded embodiment of a device according to the invention, as shown in Figures 1 and 2. In this embodiment is additional a reagent container (22) containing the reference electrolyte solution. Via a metering device (24), for example a piezoelectric Microdispenser, can be the corresponding volume of the reference electrolyte solution be introduced through a nozzle (25) in the closed device. Analogous may also contain other liquids, such as calibration solutions or cleaning solutions be introduced into the device. This can also be several Reagent container to be connected to the device.

FIG. 5:

FIG. 5 shows a sectional view of an embodiment of a device according to the invention Device which for determining analytes, for example ions, with Help of thick film electrodes is suitable. The principal Structure of the device corresponds to Figures 1 and 2. The sensor electrodes (14) and (15) are not pen-shaped electrodes in this embodiment but in the form of thick-film electrodes with a thickness in the micrometer range applied to the underside of the lid (2). The contact the thick-film electrodes (14) with the liquid sample (19) to be examined or the contacting of the thick-film electrode (15) with the reference electrolyte solution (20) takes place in this embodiment in particular by a spatially limited lowering of the lid in the area of the investigation (21). For this purpose, in the present embodiment, certain areas (3) of the lid formed elastically, so that the area of the lid, the contains sensory electrodes for determining the analyte on the substrate (1) the transport level can be moved and the contact between the thick-film electrodes and the liquid volumes can be done. Such elastic regions can be produced, for example, by so-called hard / soft injection molding processes, as described in European Patent EP 0 779 226 are to be obtained. In the present embodiment, the lowering takes place the sensory area (21) by a stepping motor (29), which via a Shaft (26) in the area of the sensory electrodes with the top of the lid is connected and so the sensory area on the substrate of the transport plane can move away or away from it. This area can be after the measurement again be moved away from the substrate of the transport plane so as to to allow removal of the liquids in the waste container (4). In other embodiments, not shown, also the whole lid on the other level for determining the analyte to be moved or the thick-film electrodes are located on areas of the lid that are permanently one Have reduced distance to the substrate of the transport plane.

FIG. 6:

FIG. 6 shows a sectional view of an embodiment of a device according to the invention Device which is suitable for carrying out PCR reactions, in particular for Determination of analytes by means of real time PCR, is suitable. The principal Structure of the device corresponds to Figures 1 and 2, however, due to the different detection techniques sensory electrodes and the corresponding Contacts in this embodiment omitted. Instead Are located in the lid (2) a plurality of heating elements (9), which on different Temperatures can be adjusted and which the underneath Adjust PCR reaction mixtures to the temperature required for the corresponding Reaction step of the PCR is needed. Excess heat can by means of cooling devices, realized here by a fan (10), dissipated become. The heat dissipation is preferably on the cover side by direct contact with the liquid with additional mixing of the reaction mixture, however Embodiments are also conceivable that without additional mixing of Reaction mixture or with non-direct heat transfer or with lateral or bottom-side heat supply work. In the illustrated embodiment are the heating elements (9) in permanently lowered areas (21) of the lid, allowing direct contact with the reaction mixture and therefore a very rapid temperature exchange can only take place at these specific locations, without overheating other areas of the device thereby. Analogous to the aforementioned embodiments, however, there are mentioned Variations in the construction of the device, in particular temporarily lowerable Heating elements, also possible. The reaction mixture is carried out the PCR moves in a specific order across the transport plane and comes in the areas of the heating elements in contact with these, so that there temperature required for the respective reaction step is achieved. For the Next PCR cycle, the reaction mixture is back to the initial position transported and the steps of different temperatures will be repeated run through. The detection of the analyte, in particular of a specific nucleic acid, takes place in a manner known to those skilled in the art. In the illustrated Device, the detection of nucleic acids by fluorescence optical Method. Here, the excitation light (27) for the real time PCR probes irradiated from below and the emitted fluorescent light (28) is also from measure again below. This is due to the present design and in particular in other arrangements of the heating elements or indirect temperature transmission or the use of transparent materials, the beam paths also different. It is also possible, the heating elements ring shape, so that the optical determination through the opening in the Ring center can be done.

FIG. 7:

FIG. 7 shows an expanded embodiment of a device according to the invention the example of an extension of Figure 6, with which the implementation of washing steps in a closed device is possible. To do this the substances, in particular the analytes, for which a media change is performed is to be, first in the expert known manner of magnetic Particles bound. Subsequently, the liquid volume with the so treated substances moved to a specific location within the device, which is located below a horizontally movable magnet (8). Becomes The magnet now lowered (shown in the figure), learn the magnetic Particles and attached substances attract and become held the magnet at the bottom of the lid. The liquid volume can now be transported away without being bound to the magnetic particles Substances are also transported away. Then another Fluid volumes of other composition are moved to this location. Now, when the magnet moves back up, the magnetic attraction decreases between magnet and the magnetic particles with the bound Substances, so that the substances are distributed again in the new liquid volume can. After this washing step, the liquid segment can now have more Undergo reaction steps, in particular as related to the description of Figure 6 are executed.

FIG. 8:

FIG. 8 shows a plan view of an embodiment of a device according to the invention Device for determining analytes by means of a viscosity measurement suitable is. The basic structure of the device corresponds to FIG. 1. The change in viscosity of the reaction mixture in position (21) can with time by means of the electrodes (30) by means of a determination the influence of surface acoustic waves are tracked as it For example, in WO 01/20781 is described. This can reduce the clotting time a sample are determined. After the reaction becomes a regeneration reagent sent over the preferred trajectories (18). This too will be in the Waste container transported. The device is ready for another measurement.

Claims (14)

Method for determining an analyte in a liquid, wherein a) a liquid volume to be examined is applied to a substrate of a transport plane, b) the liquid volume to be examined is moved on the substrate of the transport plane to a location of the examination, c) the liquid volume to be examined is additionally brought into contact with a sensory element at the location of the examination, which is located in a detection plane opposite the substrate of the transport plane, d) the analyte in the liquid volume to be examined is determined by the sensory element, characterized in that the liquid volume in step b) is in contact exclusively with the substrate of the transport plane. A method according to claim 1, characterized in that the analyte is determined directly by a specific sensory element. A method according to claim 1, characterized in that the analyte is determined indirectly by a specific detection reaction or interaction at the site of the study. A method according to claim 2, characterized in that the determination of the analyte by using analyte-specific electrodes, in particular ion-selective electrodes or gas electrodes, by amperometric or potentiometric sensor electrodes or by direct optical methods. A method according to claim 3, characterized in that the determination of the analyte is carried out indirectly by the detection of a specific interaction with a binding partner or a specific reaction of the analyte with detection reagents. Method according to one of claims 1 to 5, characterized in that the volume of liquid is moved by means of processes based on surface acoustic waves or electrowetting. A method according to any one of claims 1 to 6, characterized in that the contact of the sensory element with the liquid volume to be examined is achieved by a permanent change in the distance of the sensory element or the detection plane of the transport plane at the site of the investigation. Method according to one of claims 1 to 6, characterized in that for the determination of the analyte, the contact of the sensory element with the liquid volume to be examined by a temporary change in the distance of the sensory element or the detection plane of the transport plane. Device for determining analytes in a liquid, which is a substrate of a transport plane, via which the liquid volume to be examined is moved from a sample application site to a location of the examination, and at least one sensory element for determination of the analyte, which lies in a detection plane opposite the transport plane contains, contains,
characterized in that the liquid volume is in contact with the substrate of the transport plane during the movement to the place of the examination and is additionally brought into contact with the sensory element only for the determination of the analyte. Apparatus according to claim 9, characterized in that in the device additional elements are integrated, which can generate the forces necessary for the movement of the liquid volume and transferred to the liquid volume. Device according to one of claims 9 or 10, characterized in that the device is designed in a closed design, which additionally comprises one or more sample or Reagenzauftragezonen and / or a waste container. Device according to one of claims 9 to 11, characterized in that the contact of the sensory element with the liquid volume to be examined is achieved by a permanent change in the distance of the sensory element or the detection plane of the transport plane at the site of the investigation. Device according to one of claims 9 or 11, characterized in that for the determination of the analyte, the contact of the sensory element with the liquid volume to be examined achieved by a temporary change of the distance of the sensory element or the detection plane of the transport plane, in particular at the site of the investigation is, preferably by temporary approach of the sensory element to the substrate of the transport plane. Device according to one of claims 9 to 13, characterized in that for the detection of the analyte by means of molecular biology amplification amplification additional temperature-controlled areas are integrated into the detection and these tempered areas are designed such that for temperature adjustment of the reaction mixture, the contact of the temperature-controlled area with the reaction mixture a) a permanent change in the distance of the detection plane of the transport plane in the temperate areas or b) a temporary change in the distance of the tempered region or the entire detection plane from the transport plane is achieved.

Images