DE102005048233A1 - Apparatus and method for handling a liquid sample using a siphon structure - Google Patents

Abstract

An apparatus for handling a liquid sample comprises a body having a chamber and an outlet channel. A detection structure is arranged in the chamber, which enables a property of the sample to be detected. The outlet channel is fluidly connected to the chamber and has a siphon structure which, in a given centrifugal force field, leads to a defined filling level of the liquid sample in the chamber. Such a device is particularly suitable for carrying out mifroarray experiments.

Description

The The present application relates to a method and an apparatus to handle a liquid Sample using a centrifugal siphon structure, the are suitable to carry out from microarray experiments to support.

One Microarray is a parallel arrangement of a plurality of different, but defined "catcher structures", which are also called reaction points can be in a miniaturized grid (for example, 500 microns) on a mostly flat substrate. The catcher structures can For example, catcher molecules, such as DNA, cDNA, Proteins, antibodies, biological Cells or the like, be. A "microarray-based Test "allows the Detection of the molecules complementary to the capture molecules. Microarray-based Tests are great economic interest, for example in gene expression analysis, SNP analysis (SNP = Single Nucleotide Polymorphism) or for personalized medicine.

A "microarray-based Test "consists of one Procedure with several substeps. First, a defined microarray, So the substrate with the immobilized capture molecules, in contact with the examining liquid brought so that the complementary molecules react with the catcher molecules can. The reaction can take up to several hours and is from the dependent on characteristic times, it takes until the complementary molecules have reached the catcher molecules and reacts there have hybridized, for example, a DNA.

By continuous "stirring" or a suitable fluid guide can the complementary molecules very much catcher molecules be brought very close so that the diffusion lengths are strong shortened and thus the durations for the reaction, for example, the hybridization, greatly reduced can be. After the reaction of the molecules with the microarray further process steps, such as washing the substrate and thus the microarray, d. H. the removal of unbound molecules by exchanging the liquid to be examined with a defined buffer, or feeding of reagents, for example fluorescently labeled detection antibodies the microarray.

According to the state In the art, for example, microarrays are processed by the sample and the relevant reagents are pipetted manually. Due to the planar surface of the substrate, typically in the form of a microscope slide here the consumption of sample and reagents high. Besides that is the overflow of the Microarray reaction points with the sample to be examined are not controlled. Due to the non-continuous closed substrate it can very quickly lead to drying effects at individual reaction points come that negatively affect the outcome of the experiment.

Out the prior art, it is also known, microarrays in one process a closed fluidic structure. Here are it technical solutions For example, by a targeted mixing of the sample in reaction chambers taking advantage of surface acoustic waves. Such techniques were for example from the company Advalytix AG (www.advalytix.de) disclosed.

A alternative technique was a targeted mixing of the Sample in reaction chambers by a coupled rotational movement to perform two axes. Such a technique is available at M.A. Bynum et al., "Hybridization Enhancement using Microfluidic Planetary Centrifugal Mixing ", Analytical Chemistry, Vol. 76, No. 23, December 1, 2004, pages 7,039-7,044. According to this technique Samples are applied to seal slides and with a Microarray covered to form a chamber. The chamber will then used in a planetary centrifuge. The centrifuge Turn the chamber around one outside the chamber axis of rotation at a rotational speed of 1,200 revolutions per minute. In addition, the chamber still at a rate of 10 revolutions per minute about its own axis turned.

M. Grumann u. a., "Batch Mode Mixing on Centrifugal Microfluidic Platforms ", Lab Chip, 2005, 5, pp. 560-565 a mixing of liquids in a mixing chamber in which the mixing chamber is in rotation with changing periodically Is subjected to rotation.

Johan Vanderhoeven et al., "DNA Microarray Enhancement Using a Continuously and Discontinuously Rotating Microchamber ", Analytical Chemistry, Vol. 77, no. 14, 15 July 2005, p 4474 bis 4480, describe a DNA microarray hybridization in which a set of rotating, circular Chambers covering the microarray area at a depth of 1.6 to 70 μm is placed on the same. A substrate in which the chambers are formed are set in rotation while the microarray is kept stationary becomes.

Disadvantages of the known state of the art for processing microarrays are the necessary ones diger active and complex systems for excitation and control to achieve a targeted mixing of the sample in reaction chambers.

The The object underlying the present invention is that an apparatus and a system for handling a liquid sample to create that allow it drying of the detection structure, in particular during the typically on the hourly scale reaction with the sample is avoided, even if successively different Liquids too fed to a detection structure should be.

The present invention provides an apparatus for handling a liquid sample, having the following features:
a body having a chamber and an outlet channel,
wherein in the chamber, a detection structure is arranged, which allows detection of a property of the sample, and
wherein the outlet channel is fluidically connected to the chamber and adjusts the level in the chamber according to the siphon principle.

The present invention further provides a method of handling a liquid sample, comprising the steps of:
Placing the liquid sample in a chamber in which a sensing structure enabling detection of a property of the sample is disposed, wherein an outlet channel having a siphon structure is fluidly connected to the chamber; and
Rotating the chamber and the outlet channel to produce a centrifugal force field, which results in a defined filling level of the sample in the chamber by a siphon structure.

Under a siphon structure is generally a gravitational field, in the Case of the present invention, the centrifugal field, exposed Structure to understand which a reservoir and a connecting channel comprising one end connected to the reservoir and the other end has an outlet. The system is with a liquid at least partially filled.

To The system now strives for the principle of communicating tubes a hydrostatic equilibrium state, in which all Menisci take the same position in the direction of the force field. Is the outlet channel designed so that it follows the principle the communicating tubes Completely with liquid filled, flows, if the position of the outlet below the liquid level in the hydrostatic Balance is as long as liquid from the outlet until the liquid level in the reservoir at the height the outlet is located. In sanitary engineering, the continuous liquid column of the Connection channel as odor stop, which is odor-proof even after rinsing remains.

As soon as the connection channel completely with liquid filled is, the liquid level can also independently of the course of this connecting channel solely by the height of his Outlet be adjusted. By lowering the outlet below of the reservoir bottom, the reservoir is emptied as long as the continuous liquid column not is interrupted. Is the connection of the connection channel for example, at the bottom of the reservoir, the reservoir is completely emptied.

The full filling The siphon can either by the principle of communicating tubes through fill up into the reservoir until the common liquid level in the hydrostatic Equilibrium state above the highest point of the connection channel lies, and / or by the capillary driven filling of Channel.

When Siphon effect is here generally the regulation of the level in a reservoir through the course and the position of the connection channel be understood on the principle of communicating tubes.

By providing the outlet channel with a centrifugal siphon structure is it possible according to the invention to ensure that the detection structure does not dry out, i. always with liquid is covered, even if successively different liquids be introduced into the fluid chamber. That's the way it is, for example during execution required by microarray experiments, successively different Liquids on pass the microarray, which by the solution approach according to the invention advantageously possible is without running the risk that the microarray dries out.

at embodiments According to the present invention, the method may further comprise a step of Rotating the chamber with a time-varying rotary vector, the having multiple accelerations and multiple decelerations, by hydrodynamic inertial effects convection currents of the sample in the chamber to generate the sample at the detection structure pass by. Optionally also phases with temporally constant or vanishing rotation vector added become.

Accordingly, the inventive Device includes a drive device configured to subject the chamber to rotation and a controller configured to control the drive device to rotate the chamber with a time-varying rotational vector that includes multiple acceleration and multiple deceleration to generate by hydrodynamic inertial forces convection currents of a sample located in the chamber to guide the sample past the detection structure. Such embodiments are based on the recognition that convection currents generated by rotation with a time-varying rotary vector can advantageously be utilized to pass a large portion of a sample arranged in a sample chamber past a detection structure, or around the parts of a sample containing the sample Detection structure is exposed to change in an easy and fast way.

at preferred embodiments According to the invention, the detection structure is represented by a microarray, i. H. a parallel arrangement of a plurality of different, but defined catcher structures or catcher molecules that on a carrier are immobilized, formed.

In this regard is suitable the present invention in particular for the processing of Microarrays, wherein drying of the microarray are prevented can and in preferred embodiments a quasi-instantaneous active introduction of sample and reagents to the reactants in the microarray points by rotating the chamber with a time-varying Rotary vector, which as a shaking mode can be designated takes place. Furthermore, carried by, driven by the centrifugal field and possibly capillary forces, a quick removal unbound reactant from the microarray points, i. the individual catcher structures or catcher molecules.

at preferred embodiments of the present invention form a microarray body and a lid together a closed reaction chamber. By alternating Rotational movements of the reaction chamber can cause convection in the chamber brought which is the coupling (between sample and microarray) in one Accelerated microarray experiment. Thus, due to a forced Convection of a sample arranged in a reaction chamber Time for example a hybridization can be reduced.

at preferred embodiments can the reaction chamber completely with liquid filled be.

at embodiments According to the present invention, the chamber may be formed in a body, being the body a substrate and a cover chip has. One or more such Body can in a rotor can be used, which via a rotary motor in rotation is displaceable. The detection structure, for example the microarray, may be immobilized on the substrate while in the lid chip a channel structure, which has at least the reaction chamber and the outlet channel, is structured. Alternatively, the detection structure on the Part of the body, For example, the lid, be immobilized, in which the channel structures are formed while the lid can be a planar member. The channel structure can one or more inlet regions, one or more sample chambers, For example, reaction chambers, and one or more outlet areas exhibit.

at embodiments According to the present invention, the body itself as a body of revolution, for example a disc, be formed, which is rotatable about an axis of rotation is. Such a rotary body can also be formed of substrate and cover chip and a Channel structure required to implement the present invention or for parallelization a plurality of corresponding channel structures, the star-shaped are arranged on the disc.

In alternative embodiments of the invention, the detection structure may comprise a sensor structure comprising one or more sensor regions responsive to a sample located in the region thereof to enable conclusions to be drawn about properties of the samples. Examples of such sensor structures are oxygen sensors, CO ₂ sensors or biosensors that use biomolecules to detect properties of a sample.

The channel structures are preferably designed such that the interaction of centrifugal force and capillary force with synchronized sample addition and reagent addition, for example, allows complete processing of a microarray experiment. In the centrifugal force field, the siphon structure generates a course of the filling level defined by the time curve of the rotational frequency and the liquid volumes added at specific times, which allows precise control of the reaction conditions in the reaction chamber. In particular, when carrying out a microarray experiment, the siphon structure can cause the reaction space to always be filled with liquid at least so far that the microarray is covered by the latter when the sample, a washing liquid and reagents are fed successively into the reaction space. Thus, the microarray can be processed under continuously controllable fluidic conditions, as in the centrifugal force field of the siphon Ka nal determines the level in the reaction chamber.

The siphon principle also shows that the newly introduced volume in an already completely filled siphon channel corresponds to the displaced volume. To ensure complete fluid exchange in the chamber, the newly introduced volume must therefore at least equal the chamber volume. Under laminar conditions, which are typical in the very shallow chambers (at typical aspect ratios well below 1:10) and cause straight mixing problems, the volume displacement can be hydrodynamically designed so that the newly introduced will not be flushed out. Ideally, takes place in the chamber 46 So a complete volume exchange instead. In embodiments of the invention, the inlet is in the siphon structure of the outlet channel in a radially outer region of the chamber, so that the supplied fluids initially remain in the chamber and displaces only the volume that has already been in the chamber, out of the chamber becomes.

The Method can be used in embodiments the invention, a successive introduction of different liquids into the chamber. According to the invention, one or more liquids be supplied in different ways to the chamber, e.g. centrifugal or by pipetting or pumping systems. Furthermore, according to the invention instead a centrifugal pre-filling the Siphon structure also carried out a purely capillary pre-filling of the siphon structure.

The The present invention is in accordance with preferred embodiments thus in an apparatus and method for processing Microarrays on a planar substrate, wherein the invention Integration of the typical example described below by way of example Steps of a microarray-based experiment allows. These steps involve adding the sample to a reaction chamber and blocking them, optionally washing several times the reaction chamber and thus the microarray, the detection, d. H. dyeing, of the microarray and a following, again possibly multiple Washing the microarray. Also reading the microarray, the on any conventional Way could be done to get integrated.

Consequently allows the present invention provides a nearly complete integration of all necessary Steps to process a microarray-based experiment, whereby the reduction of the manual work steps helps, the To increase reproducibility of microarray-based experiments. Of the Body, in which the fluidic structures are formed, preferably consists of a substrate and a lid, can be produced easily and inexpensively and can therefore be used as a disposable article.

at In a pilot experiment, the reaction chamber had a volume of about 50 μL, the total volume consisting of sample, reagents and buffers at the performed Experiment at only 500 μL was. This generally represents a significant reduction in consumption the sometimes very expensive fluids Due to the optimized hydrodynamic conditions, by the application of rotation with a time-varying Rotational vector can be achieved and the alternative or supportive by a meandering reaction chamber can be achieved agreed reduce the process time to 45 minutes in the pilot experiment. there deleted the vast majority of these Time on the reaction / incubation between the initially introduced Sample with the detection structure while washing in less than a minute has ended. Generally, another is drastic Acceleration of the process time as well as a considerable reduction of the Liquid volumes conceivable.

The usable according to the invention closed reaction chamber allows compared to a non-capped substrate that microarray-based Experiment permanently in a controlled environment, which runs In particular, it prevents the microarray spots from drying out. Especially allows the optional "stirring" in the reaction space by rotating with a temporally variable rotation vector a shortened process duration, while the fluidic "siphon structure" a controlled Environment supplies.

preferred embodiments The present invention will be described below with reference to FIG the enclosed drawings closer explained. Show it:

1 and 2 schematically a plan view and a cross-sectional view of an embodiment of a device according to the invention, wherein 2 schematically a cross-sectional view along the line XX of 1 represents.

3 to 5 schematic embodiments of channel structures of embodiments of a device according to the invention;

6a and 6b schematic cross-sectional views for illustrating an embodiment of the method according to the invention;

7 the results of an experiment carried out using the invention;

8th Examples of temporally variable rotation vectors that can be used according to the invention;

9 an exemplary frequency protocol for performing a microarray experiment and the resulting level height in the chamber.

An embodiment of the device according to the invention will now be first on the basis of 1 and 2 explained.

The device comprises a rotor 10 that with a wave 12 connected by a rotary motor 14 is drivable. The rotor 10 can in any way, for example on a step portion of the shaft 12 to be appropriate. The rotary motor 14 is with a controller 16 which is designed to set the rotor in the required manner in rotation.

The rotor has four receiving areas 20 for receiving modules according to the invention containing fluid structures 22 , The modules consist in the embodiment shown of a substrate 24 and a lid 26 wherein fluid structures in the substrate 24 are formed. The fluid structures include, as discussed below with reference to FIG 3 is explained in more detail, a reaction chamber 30 , an outlet channel 32 with a centrifugal siphon structure 32 , a waste reservoir area 34 as well as two inlet channels 36 and 38 , In the embodiment shown, the fluid structures are in the substrate 24 structured. Alternatively, the fluid structures could also be structured in the lid or in the lid and substrate. The combination of substrate and lid creates an arrangement which contains a reaction space and channel systems for the supply and removal of samples or analytes, reagents and / or washing liquids to the reaction chamber.

By the control device 16 becomes the rotary motor 14 controlled such that the rotor, and thus the modules 22 , are subjected to a rotation in order to carry out the method according to the invention.

Exemplary channel structures will now be described with reference to FIGS 3 and 4 described. In preferred embodiments, the fluidic structures or channel structures are formed using a planar substrate on which the microarray is immobilized while a lid chip is patterned to realize the fluidic structures.

At the in 3 In the example shown, the fluidic structures comprise an inlet area 40 for a sample or an analyte and an inlet area 42 for reagents. The inlet area 40 is via an inlet channel 44 with a reaction chamber 46 connected while the inlet area 42 via an inlet channel 48 with the reaction chamber 46 connected is. The inlet channels 44 and 48 are with respect to a centrifugal force system (see arrow F _v in 3 ) radially inward to the reaction chamber 46 connected. Radially outward is an outlet channel to the reaction chamber 50 connected, which is such a siphon structure 52 which initially consists of a radially outwardly extending channel section 52a , then a radially inwardly extending channel section 52b and then in turn from a radially outwardly extending channel section 52c is formed. The radial position of the outlet of the channel structure is below the bottom of the reaction chamber 46 , ie Δr <0. A vent 54 is intended for the siphon structure. The vent 54 can optionally be hydrophobized completely or in sections. The outlet channel 50 empties. in a waste reservoir 56 , The vent 54 is in the waste reservoir 56 intended. At the end of the exhaust duct 50 Optionally, a hydrophobized section 57 be provided.

The siphon structure 52 is designed to set a defined liquid level in the reaction chamber at a given centrifugal force field determined by the rotational speed which results in the centrifugal force F _v , the dimensions of the fluidic structures and the liquids used, upon initial filling with the sample 46 to create. Preferably, the structure is designed such that the reaction chamber 46 in this phase is always completely filled with liquid.

The inlet areas 40 and 42 have inlet area openings 40a and 42a on. When filling the two inlets, each inactive channel serves as a vent. In 4 An alternative structure is shown where all the fluids pass through a single channel 84 be fed, but this makes the vent difficult. The channel 84 is at its radially inner end with an inlet area 82 connected to an inlet area opening 82a and at its radially outer end with a chamber 80 connected.

In the embodiments of 3 and 4 corresponds to the coordinate Δr of the radial height difference relative to the outlet of the chamber in which a detection structure 60 , For example, a microarray is provided. If the initially empty chamber is filled with the detection structure with a volume, so that the liquid level in the equilibrium state of the centrifugal field below is located halfway from the radially innermost position of the siphon channel, this liquid level remains constant at Δr> 0, regardless of the rotational frequency. In this phase, the sample is incubated with the microarray in the shaking mode in this embodiment. On the other hand, if the siphon channel is completely filled with fluid up to its outlet, the fluid from the chamber will continuously flow into the outlet during centrifugation. Such filling can take place for example by the capillary force at low speeds or at rest structure, or by adding a volume of liquid that forces an equilibrium liquid level above the radially innermost point of the Siphonkanals r _max (temporary).

In preferred embodiments of the invention, the channel structures are formed in the cover chip, wherein the cover chip is so merged with a microarray substrate that in the reaction chamber, the microarray 60 is arranged. The walls of the channel structures preferably have hydrophilic properties. The inlet area 40 and the inlet channel 44 serve to sample liquid by centrifugal force on the rotating arrangement of the reaction space 46 supply. The inlet area 42 and the inlet channel 48 serve to reagents by the centrifugal force on the rotating arrangement of the reaction space 46 supply. The outlet channel 50 The purpose of this is to leave the first sample in the chamber at any high speed and during the shaking mode, thus maintaining a constant liquid level in the reaction chamber 46 adjust. Preferably, the reaction chamber 46 always completely filled with liquid in this phase and it is thus reliably prevented drying out of the reaction chamber and thus of the microarray arranged therein. Already in the reaction chamber 46 located liquid is displaced by the subsequently supplied liquid volumes in the waste area. The inlet areas 40 and 42 have the openings 40a and 42a either in the lid chip or in the substrate to allow them to be filled with the respective liquids, either manually or automatically. Furthermore, the vent includes 54 an opening in either the lid chip or the substrate to allow venting.

One embodiment a method according to the invention will now be based on performing a microarray experiment described.

First, a sample liquid, ie an analyte, is introduced into the reaction chamber 46 introduced by the inlet area 40 filled with the sample liquid and at the same time or subsequently the channel structure (for example by the rotary motor 14 with the associated control device 16 . 2 ) is applied with a suitable rotation to the liquid by the centrifugal force F _v through the inlet channel 44 in the reaction chamber 46 contribute. The introduced volume is chosen so that the centrifugal force in the hydrostatic equilibrium initially sets a liquid level above the detection structure, but below r _max , so that the reaction chamber can not yet be centrifugally emptied by the siphon.

After the reaction chamber has been filled, it is then subjected to a time-variable rotary vector which has a multiple acceleration and a multiple deceleration. As a result of the rotation of the arrangement with a time-variable rotary vector, hydrodynamic inertial forces generate convection currents of the liquid located there within the reaction chamber. Thus, the length of time for the mixing of complementary molecules in the sample to the capture molecules by a specific "stirring" in the reaction chamber 46 located liquid can be reduced. Due to the convection currents, molecules that can be far away from the capture molecules in the stationary case are also transported close to the immobilized capture molecules. Furthermore, unbound reactants are rapidly removed from the capture molecules.

After a sufficient time for the processing of the microarray time is then over the inlet area 42 a washing liquid in the reaction chamber 46 introduced by centrifugal force through the inlet channel 48 , This will put you in the reaction chamber 46 Sample liquid through the outlet channel 50 displaced and filled the siphon structure centrifugally or by the capillary force at a suitable small centrifugal field. With a completely filled siphon, a continuous evacuation of the reaction chamber takes place in the centrifugal field 46 instead of.

After feeding the washing liquid can over the inlet area 42 and the inlet channel 48 taking advantage of the centrifugal force further reagents, such as fluorescently labeled detection antibodies in the reaction chamber 46 be introduced. This is followed by feeding a washing liquid and its centrifugally driven outflow through the siphon. Subsequently, an evaluation of the microarray can take place in any suitable manner.

With regard to the channel structures, it should be noted that in 3 the inlet channels 44 and 48 as well as the outlet channel 50 represent the flow-determining channels, ie have a cross section through which the hydrodynamic flow resistances are defined.

In 5 is schematically shown a channel structure whose outlet channel 70 an alternative siphon structure 72 having. The siphon structure includes a radially outwardly extending portion in the flow direction 70a and a radially inward extending portion in the flow direction 70b in a waste reservoir 76 that with a vent 76a is provided, flows. This structure, which is cut off at the highest point of the siphon r _max, is based directly on the principle of communicating tubes in the centrifuge field. In hydrostatic equilibrium provides a liquid level .DELTA.R> 0 above r _max complete filling and thus also the determination of the equilibrium liquid level to r _max safe. The end of the siphon channel at r _max is preferably above the detection structure and thus ensures a complete filling of the same, as again by the level 58 is displayed.

With the described apparatus and the described method, an experiment was carried out, the course of which in the 6a and 6b is shown schematically and its results in 7 are shown. More specifically, two experiments were carried out with the in 6a experiment shown a microarray substrate 90 was used in which the reaction chamber 92 is structured and on which the microarray 94 is immobilized. The substrate used was a polymer substrate, and in particular a substrate made of COC (cyclic olefin copolymer).

According to the experiment 6b became a non-structured substrate and in particular a PDMS substrate 96 (Polydimethylsiloxane substrate) used without channel structures.

at In both experiments, BSA (bovine serum albumin) was used the well-documented EDC-NHS affinity ligand coupling to the respective substrate immobilized to the surface density increase the immobilized capture molecules.

The corresponding microarray substrates are below point 1 in the 6a and 6b shown. The substrates were then provided with a respective lid, according to 6a an unstructured lid 98 is used while according to 6b a reaction chamber 100 in the lid 102 is structured. In doing so, the lid provides 98 a PDMS lid while the lid 102 represents a COC lid. Subsequently, the sample having a known target concentration cBSA of mouse anti-BSA antibodies was introduced into the reaction chamber as in point 2 of the 6a and 6b you can see. Subsequently, sheep anti-mouse Cy3 antibodies were added, see item 3 in 6a and 6b , The specific antigen-antibody complexes are formed. This is followed by a washing step, followed by fluorescent detection antibodies 104 be supplied with which the said complexes are marked.

The results obtained are in 7 shown, with the curve 110 the COC microarray substrate with channel structure affects while the curve 112 relates to the PDMS microarray substrate without channel structure. 7 shows that a clear and reproducible correlation is obtained for varying target concentrations c _BSA and the resulting fluorescence signal I over a working range of at least 3 decades. The entire microarray experiment was completed in 45 minutes, with all steps fully automated.

Possible rotation protocols for acting on the channel structures with a temporally variable rotation vector, which has a multiple acceleration and multiple deceleration and possibly also phases with a constant rotation vector are in the 8a . 8b and 8c shown. 8a shows a switching between maximum rotational frequencies f _max with different directions of rotation. For example, the maximum rotational frequency may be 8 Hz, while the maximum rotational acceleration may be ± 32 Hz / s. 8b shows a switching between a maximum rotational frequency f _max and a rotational frequency of 0, so that the rotation protocol as shown in FIG 8th can be performed using centrifuges, which are operable in one direction only, can be performed. Finally shows 8c a rotation protocol in which after accelerating to the respective maximum rotational frequency, a short rotation takes place at this maximum rotational frequency.

9 shows by way of example the respective frequency protocols v (t) and level heights in the reaction chamber Δr as a function of the time t for the siphons in the manner of 3 and 5 shown. Regarding the level heights the curve refers 120 to the siphon structure after 3 while the bend 122 to the siphon structure after 5 refers. The time scale is not linearly scaled here, for example, the sample incubation time in shake mode is typically at least a factor 10 longer than the subsequent phase of purging the wash buffer. In the resting phases Δt ₁ and Δt ₂ liquid volumes are added.

Like the curve 120 in 9 it can be seen, the microarray structure is after 3 completely covered during shaking mode. On the addition of a subsequent volume and the so connected complete filling of the siphon, the chamber is continuously emptied during rotation, such as the section 120a the curve 120 can be seen.

Notwithstanding the illustrated preferred embodiments, numerous variations of the present invention are possible. So could instead of the described disc-shaped rotor 10 a four-arm rotor can be used. Again alternatively, the body in which the fluid structures are formed could be formed as a rotational body, for example as a disc, which is rotatable about an axis of rotation thereof. In this body, a plurality of channel structures could be arranged radially star-shaped, comparable to the arrangement of the modules 22 in the rotor 10 ,

at preferred embodiments In accordance with the invention, the channel structures comprise one or more inlet channels for liquid supplied by centrifugal force of the reaction chamber. Alternatively, however, could the liquid get into the reaction chamber in any other ways, for example about a feed channel under exercise of a Pressure or by manual filling.

Of the Rotary drive, for example, can be designed to be PC-controlled to carry out a frequency protocol, around a time-dependent To generate centrifugal pressure to be carried out for each Steps to precisely control the flow rates and timing.

The the present invention thus provides apparatus and methods which are particularly suited to microarray experiments to an increasingly automated Way to perform. In particular, the present invention provides a way sample liquid and the molecules contained within efficiently catcher molecules of the Supply microarrays and while of the entire experiment to prevent the microarray from drying out. Thereby can reliable, reproducible results obtained with only a very small dead volume become. The present invention is particularly suitable for the Use in so-called "lab-on-a-disk" systems, the one flexible platform for a complete one represent integrated and fast processing of experiments.

The present invention enables the implementation of microarray experiments with a reduced amount of time, one fast and homogeneous reaction, an automated washing process, a reduced consumption of sample and reagents, as well as a integrated waste handling. By the elimination of uncontrolled drying steps The sensitivity of the microarray experiment can be further improved by the siphon structure elevated become. In this way, the use of separate devices, like slide-washing devices and the like become obsolete and handling steps are automated. Finally, the Symmetry of the rotor or the body of revolution potentially that multiple microarray experiments carried out in parallel become.

Claims (22)

Device for handling a liquid sample, comprising: a body having a chamber ( 30 ; 46 ; 80 ; 92 ; 100 ) and an outlet channel ( 32 ; 50 ; 70 ), wherein in the chamber a detection structure ( 60 ; 94 ) is arranged, which allows a detection of a property of the sample, and wherein the outlet channel ( 32 ; 50 ; 70 ) is fluidly connected to the chamber and adjusts the level in the chamber according to the siphon principle. Device according to claim 1, further comprising a drive device ( 14 ) for rotating the body to produce the given centrifugal force field. Device according to claim 1 or 2, further comprising a control device ( 16 ) configured to drive the drive means ( 14 ) to rotate the body with a time-varying rotational vector having multiple accelerations and multiple decelerations in the same or different directions of rotation. Device according to one of Claims 1 to 3, in which the detection structure ( 60 ; 94 ) has a microarray of support structures for trapping molecules from the sample. Device according to one of claims 1 to 3, wherein the detection structure has a sensor structure. Apparatus according to claim 5, wherein the sensor structure comprises a biosensor, an oxygen sensor or a CO ₂ sensor. Device according to one of claims 1 to 6, wherein the body further comprises an inlet channel ( 36 ; 44 ; 84 ) for introducing the sample into the chamber ( 30 ; 46 ; 80 ; 92 . 100 ) by centrifugal force. Device according to claim 7, in which the body has a separate inlet channel ( 38 ; 48 ) for introducing reagents into the chamber ( 30 ; 46 ; 80 ; 92 ; 100 ) having. Device according to one of claims 1 to 8, wherein the body further comprises a waste reservoir ( 34 ; 56 ; 76 ) in which the outlet channel ( 32 ; 50 ; 70 ) opens. Device according to one of Claims 1 to 9, in which the body is a substrate ( 24 ; 90 ; 96 ) and a lid ( 26 ; 98 ; 102 ), wherein the chamber, the outlet channel and, if present, the inlet channels and the waste reservoir are structured in the lid, the substrate or both. Device according to Claim 10, in which the detection structure ( 60 ; 94 ) is immobilized on the substrate. Method for handling a liquid sample, comprising the following steps: introducing the liquid sample into a chamber ( 30 ; 46 ; 80 ; 92 ; 100 ), in which a collection structure ( 60 ; 94 ) is arranged, which allows a detection of a property of the sample, wherein an outlet channel ( 32 ; 50 ; 70 ), which has a siphon structure ( 52 ; 72 ), is fluidically connected to the chamber; and rotating the chamber and the outlet channel to create a centrifugal force field that adjusts the level in the chamber according to the siphon principle so that the sensing structure is covered by the sample. Method according to claim 12, wherein the chamber and the outlet channel with a time-varying Rotate vector, which is a multiple speeding and a multiple deceleration in the same or different Has directions of rotation. Method according to Claim 12 or 13, in which the detection structure ( 60 ; 94 ) has a microarray of capture structures for trapping molecules from the sample. A method according to claim 12 or 13, wherein the Detection structure has a sensor structure. The method of claim 15, wherein the sensor structure comprises a biosensor, an oxygen sensor or a CO ₂ sensor. The method of any one of claims 12 to 16, wherein the step of introducing the sample comprises introducing the sample through an inlet channel (10). 36 ; 44 ; 84 ) by centrifugal force. A method according to any one of claims 12 to 17, comprising the steps of sequentially introducing different liquids into the chamber ( 30 ; 46 ; 80 ; 92 ; 100 ), wherein the siphon structure causes the sensing structure to not dry out during these steps. The method of any one of claims 12 to 18, further comprising a step of introducing another liquid into the chamber (12). 30 ; 46 ; 80 ; 92 ; 100 ), thereby passing the sample through the outlet channel ( 32 ; 70 ) while the chamber and the outlet channel are rotated, the siphon structure ( 72 ) causes the collection structure ( 60 ; 94 ) while being covered by the sample or the further liquid. The method of any one of claims 12 to 18, further comprising a step of introducing another liquid into the chamber (12). 30 ; 46 ; 80 ; 92 ; 100 ) to thereby sample through the outlet channel ( 32 ; 50 ) while the chamber and the outlet channel are rotated, the siphon structure ( 52 ) causes the sample and then the further liquid to be emptied from the chamber by introducing the further liquid. A method according to claim 19 or 20, wherein the more liquid a washing liquid is. The method of claim 21, further comprising a step of introducing reagents into the chamber ( 30 ; 46 ; 80 ; 92 ; 100 ) after the step of introducing the washing liquid, whereby the washing liquid through the outlet channel ( 32 ; 70 ) is discharged while the chamber and the outlet channel rotate, the siphon structure ( 72 ) causes the sensing structure to be covered by the washing liquid or reagents during this time.