WO2009068025A1

WO2009068025A1 - Integrated separation, activation, purification and detection cartridge

Info

Publication number: WO2009068025A1
Application number: PCT/DK2007/000517
Authority: WO
Inventors: Peter Warthoe; Søren Mentzel; Klaus Rune Andersen; Jens Mikkelsen; Jacob Holst Madsen
Original assignee: Atonomics A/S
Priority date: 2007-11-26
Filing date: 2007-11-26
Publication date: 2009-06-04

Abstract

The present invention relate to a device and a method for quantitative detecting of the presence or absence of a target analyte in a liquid sample, the device comprising a reaction chamber in the form of a capillary channel having a volume of less than 200μl, a first part comprising a sample inlet for the introduction of a sample containing an analyte, and a discharge outlet for the discharge of waste products; a second part comprising means for detection of the target analyte, and a solution inlet for introduction of washing solutions and reaction mixtures; and means for transferring an immobilised analyte from the first part to the second part of the chamber and vice versa where the first and second parts are separated such that other liquid sample material may not enter the second part of the chamber.

Description

Title: Integrated separation, activation, purification and detection cartridge

Technical Field

The present invention relates to a device for quantitative detecting the presence or absence of a target analyte in a liquid sample, and to uses thereof.

The invention further relates to a method for quantitative detecting the presence or absence of a target analyte in a sample consisting of less than 200 μl

The invention further relates to a kit of parts comprising the device according to the invention and magnetic particles.

Background

Over the years, numerous simplified test systems have been designed to rapidly detect the presence of a target analyte of interest in biological, environmental and industrial fluids. In one of their simplest forms, these assay systems and devices usually involve the combination of a test reagent which is reacting with the target analyte to give a vis- ual response and an absorbent paper or membrane through which the test reagents flow.

The contact may be accomplished in a variety of ways. Most commonly, an aqueous sample is allowed to traverse a porous or absorbent member, such as porous polyeth- ylene or polypropylene or membranes by capillarity through the portion of the porous or absorbent member containing the test reagents. In other cases, the test reagents are pre-mixed outside the test device and then added to the absorbent member of the device to ultimately generate a signal.

Many commercially available devices and assay systems also involve a wash step in which the immune absorbing zone is washed free of non specifically bound signal generator so that the presence or amount of target analyte in the sample can be determined by examining the porous member for a signal at the appropriate zone.

In addition to the limitations of the assay devices and systems of the prior art, including the limitations of using absorbent membranes as carriers for sample and reagents, as- say devices generally involve numerous steps, including critical pipetting steps which must be performed by relatively skilled users in laboratory settings. Accordingly, there is a need for one step assay devices and systems, which, in addition to controlling the flow of reagents in the device, control the timing of the flow of reagents at specific chambers in the device. In addition, there is a need for assay devices which do not require critical pipetting steps and are performing in a full quantitative way.

Today most target analyte are measured using large equipment (immune analyzers) located at central laboratories. One of the major reasons for this is that no small hand- held instrument exist today that can fulfil the critical parameters for a highly sensitive, reproducible and quantitative immune as well as DNA assay.

Accordingly, an object of the present invention was to develop a handheld device and a method capable of reliably and efficiently detecting the presence or absence of target analytes in small samples.

One major concern when quantitatively detecting presence or absence of analytes in small samples is the elimination or reduction of background signal, which disturbs the reliability and reproducibility of detecting small amounts of analyte.

Accordingly another object of the present invention was to develop a device and a method for quantitatively detecting the presence or absence of a target analyte in a small liquid sample, wherein the background unspecific signal is reduced or eliminated

Disclosure of the Invention

In the experimental development leading to the present invention the inventors found that critical parameters for obtaining a highly sensitive, reproducible and full quantitative assay for quantitatively detecting presence or absence of analytes in small sam- pies are to increase the signal to noise ratio by lowing the background noise. Further, efficient mixing procedures between the target analyte and tracer/capture antibodies are preferred, as well as efficient washing procedures for lowing background noise. Even further it was found that a large reaction surface between target analyte and tracer/capture antibodies is preferred, further preffered features are efficient amplifica- tion reagent such as HRP or ALP enzyme conjugated tracer antibodies and the possibility of using temperature controlled assays. By combining microfluid and magnetic particle technology in a special constellation the present inventors found that it was possible to fulfil the critical parameters and at the same way obtaining a relative small handheld instrument (below 500 gram), capable of analysing samples of less than 200μl.

Accordingly in a preferred aspect of the invention it relates to a device for quantitative detecting the presence or absence of a target analyte in a liquid sample, the device comprising a reaction chamber in the form of a capillary channel having a volume of less than 200μl, the reaction chamber comprising:

a. a first part (fig. ref.) comprising a sample inlet (fig. ref.) for the introduction of a sample containing an analyte, and a discharge outlet (fig. ref.) for the discharge of waste products;

b. a second part (fig. ref.) comprising means for detection (fig. ref.) of the target analyte, and a solution inlet (fig. ref.) for introduction of washing solutions and reaction mixtures; and

c. means for transferring an immobilised analyte from the first part to the second part of the chamber and vice versa;

where the first and second parts are separated such that other liquid sample material may not enter the second part of the chamber.

In a further aspect the invention relates to the use of a device according to the invention for the quantitative detection of the presence or absence of a target analyte in a sample.

In a further aspect the invention relates to a method for quantitative detecting the presence or absence of a target analyte in a sample consisting of less than 200 μl liquid, comprising the steps of:

a) providing an analyte containing liquid sample consisting of less than 200 μl liquid; b) supplying the liquid sample to a first reaction part of a chamber, the chamber comprising a first reaction part and a second detection part, the two parts being physically separated such that liquid sample material cannot enter into contact with the second detection part; c) contacting the sample in the first reaction part of a chamber with an immobilisation matrix capable of capturing the analyte; d) immobilising the immobilisation matrix comprising the captured analyte; e) transferring the immobilisation matrix comprising the captured analyte to the second part of the chamber; f) remobilising and washing the immobilisation matrix comprising the captured analyte with a washing solution; g) immobilising the immobilisation matrix comprising the captured analyte; h) optionally, discarding the washing solution i) optionally, remobilising the immobilisation matrix comprising the captured analyte and repeating steps f) to h); j) transferring the immobilisation matrix comprising the captured analyte to the detector part of the second part of the chamber; and k) detecting the presence or absence of a target analyte using conventional detection means.

In a further aspect the invention relates to a kit of parts comprising a device according to the invention and a magnetic material.

Brief Description of the Drawings

The invention is explained in detail below with reference to the drawing(s), in which

Rg. 1 shows a sample device comprising a microfluid channel having three chambers (3, 5, 6). In the embodiment shown, these three compartments are to be understood as "the reaction chamber" according to the invention. (3) illustrates the first part of the reaction chamber, whereas (5 and 6) illustrate the washing part and the detector part of the second part of the reaction chamber, respectively. Fluid inlet hole (1). Fluid membrane compartment (2). First part of the reaction chamber (Serum/ plasma separation chamber) (3). Waste outlet (4). Washing chamber (5). Detection chamber (6). Magnetic particles location in washing chamber (7). Inlet channel for washing and detector solution (8). Connecting junction (10) between the fluid membrane compartment and the first part of the reaction chamber. Capillary microchannels (11) in the first part of the reaction chamber (3). Corona treatment (12) of the serum/ plasma separation chamber (3). Detector unit (14).

Fig. 2 shows the same principle as in Fig. 1 with a three dimension illustration.

A sample device comprising a microfluid channel having three chambers (3, 5, 6). Fluid inlet hole (1). Fluid membrane compartment (2). Serum/ plasma separation chamber (3). Waste outlet (4). Washing chamber (5). Detection chamber (6). Magnetic particles location in washing chamber (7). Inlet channel for washing and detector solution (8). Connecting junction (10) between the fluid membrane compartment and the serum/plasma separation chamber. Capillary microchannels (11) in the first part of the reaction chamber (3). Corona treatment (12) of the Serum/ plasma separation chamber (3). Detector unit (14). First compartment for detection solution A (9). Second compartment for detection solution B (15). Washing solution compartment (16). Fluid lid (12).

Figs. 3A to 3K show a target analyte fluid detection cycle.

In Fig. 3A, the fluid inlet lid (12a) is pushed to the left.

In Fig. 3B, between 10 — 100 uL human full fluid (blood) is taken from a finger tip (13) and directly placed in the fluid inlet hole (1).

In Fig. 3C, the fluid inlet lid (12a) is pushed over the fluid inlet hole (1).

In Fig. 3D, it is shown that after the blood separation process, the plasma/serum enters the first part of the reaction chamber (3) via special design micro structures and treatment for enhancement of capillary forces.

In Fig. 3E, a washing solution (11 ) is injected via Inlet channel for washing and detector solution (8) and the detection part of the second part of the reaction chamber (6) into the washing part of the second part of the reaction chamber (5).

In Fig. 3F, magnetic particles in washing part of the second part of the reaction cham- ber (7) are dissolved and moved into the first part of the reaction chamber (3) for incubating. In Fig. 3G, magnetic particles located in first part of the reaction chamber (3) are moved back into washing part of the second part of the reaction chamber (5) for washing.

In Fig. 3H, the detector solution (9,15) is injected via Inlet channel for washing and detector solution (8) and the detection part of the second part of the reaction chamber (6) into the washing part of the second part of the reaction chamber (5).

Fig. 3I shows the same as illustrated in Fig. 2H. The washing chamber (5) is now complete filled with detector solution form detector compartments (9, 15).

In Fig. 3J, magnetic particles (7) located in the washing part of the second part of the reaction chamber (5) are moved forward to the detection part of the second part of the reaction chamber (6) where presence or absence of target analyte are detected via a sensor unit (14).

Figs. 4A to 4C illustrate the magnetic particles motor system that moves the magnetic particles between the different chamber locations as illustrated in Fig. 2.

Fig. 4A illustrates a magnetic motor system that moves the magnetic particles located in the microfluid channel. The sample device (1) containing the magnetic particles (7) are located under the magnetic particle motor system (3) driven by an electromotor (4). The magnet (6) is located in the magnet holder (5). The magnet can move between all three chambers as illustrated in Figs. 2A - 2J.

Fig. 4B shows the same as in Fig. 4A, the magnet are positioned on top of the magnetic particles in washing chamber as illustrated in Fig. 2B.

Fig. 4C shows the same as in Fig. 4A, the magnet have now completed a cycle and moved away from the microfluid channel comprising the three chambers.

Fig. 5 shows the sensor data illustrating 3 x 8 measurement using three different concentrations of the analyte Brain Natriuretic Peptide (BNP) in serum. Green lines: BNP concentration 7.2 pg/mL; red lines: BNP concentration 64 pg/mL and blue lines: BNP concentration 205 pg/mL. Fig. 6 illustrates a sample device comprising a microfluid channel having three chambers (3, 5, 6). In the embodiment shown these three compartments are to be understood as "the reaction chamber" according to the invention. (3) illustrates the first part of the reaction chamber, whereas (5 and 6) illustrate the washing part and the detector part of the second part of the reaction chamber, respectively. Fluid inlet hole (1). Fluid membrane compartment (8). First part of the reaction chamber (Serum/ plasma separation chamber) (3). Washing chamber (5). Detection chamber (6). Magnetic particles location on detector unit (4). The most relevant part of this figure is 9a) which is a top preventing light from entering the second part of the reaction chamber from the first part of the reaction chamber. Magnetic particles may cross this barrier as they are moved along the top part of the reaction chamber.

Fig. 6B shows the same as Fig. 6A but with an alternative means (9b) for separating the first and second pars of the reaction chamber such that light may not be transferred from the first part of the chamber to the detector part of the second part of the chamber. These means (9b) are to illustrate a barrier which on demand may be inserted between the two parts.

Definitions:

In the context of the present invention, by "capillary channel" is meant a narrow tube or channel through which a fluid can pass. Preferably the diameter of a capillary channel according to the invention is less than 10 mm. Even more preferred the diameter of a capillary channel according to the invention is less than 5mm, such as less than 4 mm, or less than 3 mm or even less than 2 mm. In a most preferred aspect the capillary channel has a diameter of 1 mm or less.

Detailed description of the Invention

Signal detection in microfluidic systems are often jeopardised by a very low sensitivity requiring large amounts of analyte to generate a reliable and reproducible signal. Much effort has been put into development of more sensitive and sophisticated detection means. However, surprisingly, less has been done in order to remove or reduce the level of unspecific signal (noise). The present inventors surprisingly found that simple measures reducing the noise of the system significantly improved the reproducibility and the sensitivity of the system significantly.

The inventive concept of the present invention may be seen in general as the physical separation, in a microfluidic system, of the steps of binding and immobilising an analyte and the steps of detecting the analyte. Preferably, any signal deriving from non-analyte species (background signal) remains in the first part of the device (or the first steps in the method), whereas in the second part of the device (later steps in the method) the signal derived from the analyte, with a minimal background signal, is detected.

Accordingly, in one aspect the invention relates to a device for quantitative detecting the presence or absence of a target analyte in a liquid sample, the device comprising a reaction chamber in the form of one or more capillary channels having a volume of less than 200μl, the reaction chamber comprising:

d. a first part (fig. ref.) comprising a capillary channels having a volume of less than 200μl, a sample inlet (fig. ref.) for the introduction of a sample containing an analyte, and a discharge outlet (fig. ref.) for the discharge of waste products;

e. a second part (fig. ref.) comprising means for detection (fig. ref.) of the target analyte, and a solution inlet (fig. ref.) for introduction of washing solutions and reaction mixtures; and

f. means for transferring an immobilised analyte from the first part to the second part of the chamber and vice versa;

where the first and second parts are separated such that other liquid sample material may not enter the second part of the chamber. By other sample material is meant sample material excluding the analyte.

The reaction chamber may contain several compartments or parts. Further each part may be divided into further parts or compartements wherein specific ractions are to occur. By separating the reaction chamber in a first part for binding the analyte and a second part and detecting the analyte, a significant reduction in background signal could be obtained. In a preferred aspect the sample to be analysed preferably has a volume of less than 200μl. In an even more preferred aspect the sample to be analysed has a volume of less than 150μl, even more preferred less than 100μl, even more preferred less than 90μl, such as less than 80μl, less than 70μl or even less than 60μl. In an even more preferred aspect the sample to be analysed has a volume of less than 50μl, even more preferred less than 45μl, even more preferred less than 40μl, such as less than 35μl, less than 30μl or even less than 25 μl.

In a preferred aspect the first part of the capillary channel has a volume of less than 100μl. In an even more preferred aspect the first part of the capillary channel has a volume of less than 90μl, even more preferred less than 80μl, even more preferred less than 70μl, such as less than 60μl, less than 50μl or even less than 40μl. In an even more preferred aspect the first part of the capillary channel has a volume of less than 30μl, even more preferred less than 25μl, even more preferred less than 20μl, such as less than 15μl, less than 10μl or even less than 5 μl. The same preferred volumes apply for the second part of the reaction chamber. The reaction chamber comprises a first and a second part. In a preferred aspect both the first and the second part are made of capillary channels. The first and second part may be separated e.g. by a collection chamber from which residual sample matter and added reagents may be collected and later expelled. Such a collection chamber, and the volume thereof is not to be understood as part of the reaction chamber or the preferred volumes thereof.

In a preferred aspect of the invention the means for transferring the immobilised ana- lyte from the first part to the second part of the chamber and vice versa is an external magnetic force generating source, which can apply a magnetic field to the chamber and be moved along the edge of the chamber on demand.

In one aspect of the invention the first and second parts are separated by a collection chamber (fig. ref.). The collection chamber may serve the purpose of separating the first and second parts such that liquid sample material, other then analyte species actively transported between the first and second part, may not enter the second part of the chamber. The collection chamber also serves the purpose of an outlet for waste products such as washing solution and residual sample material. The placement of the collection chamber between the first and the second part provides that the collection chamber serves as an outlet for material from both the first and the second part of the chamber. In a preferred aspect of the invention, in order to move magnetic particles comprising the immobilised analyte most efficiently, a magnetic field is moved along the top edge (fig. ref .) of the chamber on demand.

In a preferred aspect of the invention the first and second parts are separated such that a significant part of the signal (e.g.light) may not be transferred from the first part of the chamber to the detector part of the second part of the chamber. By a significant part is meant more than 50%, such as more than 75% or even more than 90%, or even more than 99%. This may be achieved by placing the exit point from the first part and the entry point of the second part in different levels e.g. by introducing a bend on the path from the first part to the second part of the chamber, such that signal (in the form of light rays) from the first part of the chamber may not enter the detection part of the second chamber. Another possibility is introducing a bend in the second part of the chamber such that the detector part is not in line with the entry point of the analyte to the second part of the chamber. A preferred possibility is the placement of a lightim- permeable barrier between the two parts such that a significant part of the light is prevented from entering the second part from the first part. Of course the barrier must not prevent the transfer og analyte (e.g. via magnetic particles) from the first and second parts. This may be achieved e.g. as shown in Fig. 6.

Preferably, the surface structure and the colour of the internal surface of the reaction chamber, or at least the second part of the chamber, is non-reflecting and/or light absorbing, respectively. In one aspect of the invention the non-reflecting and/or light ab- sorbing surface is obtained by obscuring and/or darkening of the surface. In a preferred aspect the darkening is blackening. Most preferably the colour of the internal surface of the reaction chamber is black.

In a preferred aspect of the invention the means for detection of the target analyte are selected among surface acoustic wave (SAW) detectors, spectrophotometers, fluoro- meters, CCD sensor chip(s), CCOS sensor chip(s), PMT detector(s), or any suitable light detector.

In a preferred aspect the internal width and height of the reaction chamber, or at least the first part of the reaction chamber, is 0.1-5 mm and 0,05 - 2 mm respectively . More preferably, the internal width and height of the reaction chamber, or at least the first part of the reaction chamber, is 0.25-2 mm and 0.2 - 1 mm, respectively

In a preferred aspect the length of the reaction chamber is 2-30 mm, more preferably 5- 20 mm.

The device according to the invention may be used for the quantitative detection of the presence or absence of a target analyte in a sample. Preferably, the sample is derived from blood. In one aspect the sample is serum. In one aspect the sample is plasma. Plasma may obtained by applying an anti coagulant to the blood sample to be analysed. Preferred anti-coagulant may be selected among the group comprising K3- EDTA, citrate and heparine.

In a preferred aspect of the invention the sample is of human origin.

In another aspect the invention relates to a method for quantitative detecting the presence or absence of a target analyte in a sample consisting of less than 200 μl liquid, comprising the steps of:

a) providing an analyte containing liquid sample consisting of less than 200 μl liquid; b) supplying the liquid sample to a first reaction part of a chamber, the cham ber comprising a first reaction part and a second detection part, the two parts being physically separated such that liquid sample material cannot enter into contact with the second detection part; c) contacting the sample in the first reaction part of a chamber with an immobi lisation matrix capable of capturing the analyte; d) immobilising the immobilisation matrix comprising the captured analyte; e) transferring the immobilisation matrix comprising the captured analyte to the second part of the chamber; f) remobilising and washing the immobilisation matrix comprising the captured analyte with a washing solution; g) immobilising the immobilisation matrix comprising the captured analyte; h) optionally, discarding the washing solution i) optionally, remobilising the immobilisation matrix comprising the captured analyte and repeating steps f) to h); j) transferring the immobilisation matrix comprising the captured analyte to the detector part of the second part of the chamber; and k) detecting the presence or absence of a target analyte using conventional detection means.

By separating the steps a) - d) of binding the analyte in one compartment and the steps e) - k) of washing and detecting the analyte in a second compartment a significant reduction in background signal was observed.

In a preferred aspect the method further comprise a step a') of contacting the analyte with a biological marker, capable of binding to the analyte. The biological marker may be an antibody e.g. with enzyme horseradish peroxidise (HRP), biotin or alkaline phosphatase (ALP). Thereby the analyte may become more detectable by increasing the signal for detection. In a preferred aspect of the method according to the invention the step a') of contacting the analyte with a biological marker, capable of binding to the analyte is performed prior to step e). Thereby, the presence of unbound biological marker in the detection part of the method is minimised and the background signal is significantly reduced. In a preferred aspect of the invention the biological marker is ca- pable of reaction with a substrate whereby signal may be amplified. Accordingly, in one aspect of the invention the method further comprise a step f) of contacting the immobilisation matrix comprising the captured analyte with a substance capable of reacting with the biological marker.

In a preferred aspect of the invention the biological marker is one [or more] selected from compounds, mono-, oligo- and polyclonal antibodies, antigens, receptors, ligands, enzymes, proteins, peptides and nucleic acids. Preferably the biological marker is one or more selected from the group having the properties of light absorption, fluorescence emission, phosphorescence emission, or luminescence emission.

In a preferred aspect the immobilisation matrix comprises magnetic material. In a preferred aspect the step e) is performed by moving a magnetic source along the external edge of the first reaction chamber toward the second detection chamber.

The magnetic material is preferably selected from the group comprising magnetic particles, magnetic nanoparticles and superparamagnetic nanoparticles. It was further surprisingly observed that using magnetic particles having a non unimo- dal size distribution, such as a bimodal size distribution, a more efficient performance in terms of washing efficiency and time was obtained. Accordingly in a preferred aspect of the invention the magnetic material has an at least bimodal size distribution. In another aspect of the invention the magnetic material has a trimodal size distribution.

In a preferred aspect of the invention the conventional detection means are selected among surface acoustic wave (SAW) detectors, spectrophotometers, fluorometers, CCD sensor chip(s), CCOS sensor chip(s), PMT detector(s), or any suitable light detector.

The method according to the invention may be used for the quantitative detection of the presence or absence of a target analyte in a sample. Preferably, the sample is derived from blood. In one aspect the sample is serum. In one aspect the sample is plasma. Plasma may obtained by applying an anti coagulant to the blood sample to be analysed. Preferred anti-coagulant may be selected among the group comprising K3- EDTA, citrate and heparine. In a preferred aspect of the invention the sample is of human origin.

In one aspect, the invention relates to a kit of parts comprising a device as defined above and a magnetic material according to the invention. Preferably this kit is for use in detection of the presence or absence of a target analyte in a sample.

Examples

To illustrate the measuring principle, the analyte Brain Natriuretic Peptide (BNP) is measured in plasma using the sample device illustrated in Fig. 1.

Materials:

Samples: Three different plasma samples are spiked with the BNP analyte in the following concentration.

Plasma sample L: 7,2 pg/mL of BNP Plasma sample M: 64 pg/mL of BNP Plasma sample H: 205 pg/mL of BNP

Antibodies: MP coated BNP monoclonal catching antibody. Tracer antibody is a HRP label monoclonal BNP antibody. Tracer antibody was placed direct in blood separation filter.

Blood stabilizing reagent: EDTA are added to the blood separation membrane.

Washing solution: TBS + 0.05% tween and 0.05% BSA

Detector solution: Pierce SuperSignal ELISA Femto Maximum Sensitivity Substrate

Detector: PMT detector

Assay temperature: 23 C

Mechanics and Electronics: All mechanical parts, electronics controllers and software are produces in house by the assignee company.

Assay procedures:

A total of 24 samples (plasma sample L; plasma sample M; plasma sample H) was analysed according the procedure illustrated in table I. The numbers in () correspond to numbers in Fig. 1.

It can be observed from Fig. 5 that the three different BNP concentrations can be de- tected using the device principle described in this application.

The following parameters were important for detection the BNP at low concentrations in a reproducible manner.

• Applying a drop of blood (20 - 100 uL) directly into the analysing device. • Increase the signal to noise ratio by lowing the background noise.

• Efficient mixing procedures between the target analyte and tracer/capture antibodies.

• Efficient washing procedures for lowing background noise.

• Large reaction surface between target analyte and tracer/capture antibodies. • Efficient amplification reagent such as HRP or ALP enzyme conjugated tracer antibodies. Temperature controlled assays.

12 Magnet is moved forMPs move to the The BNP analyte are ward to the detector detector part of the measured. The amount of part of the second part second part of the light measures are in linear of the reaction chamber reaction chamber correlation with the (6). I an fast movement (6). MPs are reconcentration of BNP the magnet are returnleased into detecanalyte. ing to start position outtion solution just side microfluid channel over the light detection unit (14)

Table I: The BNP assay procedure in sample device. All position numbers is according to Fig. 1.

Conclusion

It is possible to detect the analyte BNP in concentration at 7,2 pg/mL All CV values calculated were below 15% at all three BNP concentrations (sample L, sample M and sample H).

Claims

1. A device for quantitative detecting the presence or absence of a target analyte in a liquid sample, the device comprising a reaction chamber having a volume of less than 200μl, the reaction chamber comprising:

a. a first part comprising a capillary channel having a volume of less than 200μl, a sample inlet for the introduction of a sample containing an analyte, and a dis- charge outlet for the discharge of waste products;

b. a second part comprising means for detection of the target analyte, and a solution inlet for introduction of washing solutions and reaction mixtures; and

2. A device according to claim 1 , where the means for transferring the immobilised analyte from the first part to the second part of the chamber and vice versa is an external magnetic force generating source, which can apply a magnetic field to the chamber and be moved along the edge of the chamber on demand.

3. A device according to any of the claims 1 or 2, where the first and second parts are separated by a collection chamber.

4. A device according to any of the preceding claims where the first and second parts are separated such that light may not be transferred from the first part of the chamber to the detector part of the second part of the chamber.

5. A device according to any of the claims 2-4, where the magnetic field is moved along the top edge of the chamber on demand.

6. A device according to any of the preceding claims, where the surface structure and the colour of the internal surface of the reaction chamber is non-reflecting and/or light absorbing, respectively.

7. A device according to claim 6, where the non-reflecting and/or light absorbing surface is obtained by obscuring and/or darkening of the surface.

8. A device according to claim 7, where the darkening is blackening.

9. A device according to any of the claims 6-8, where the colour of the internal surface of the reaction chamber is black.

10. A device according to any of the preceding claims, where the means for detection of the target analyte are selected among surface acoustic wave (SAW) detectors, spectrophotometers, fluorometers, CCD sensor chip(s), CCOS sensor chip(s), PMT detectors), or any suitable light detector.

11. A device according to any of the preceding claims, where the internal width and height of at least the first part of the reaction chamber is 0.1-5 mm and 0,05 - 2 mm, respectively

12. A device according to claim 11 , where the internal width and height of at least the first part of the reaction chamber is about 0.25-2 mm and 0.2 - 1 mm, respectively.

13. A device according to any of the preceding claims, where the length of the first part of the reaction chamber is 2-30 mm.

14. A device according to claim 13, where the length of the first part of the reaction chamber is about 5-20.

15. Use of a device according to any of the claims 1-14 for the quantitative detection of the presence or absence of a target analyte in a sample.

16. Use according to claim 15, where the sample is derived from blood.

17. Use according to claim 16, where the sample is serum.

18. Use according to claim 16, where the sample is plasma.

19. Use according to claim 18, where the plasma is obtained by an anti coagulant to the blood.

20. Use according to claim 19, where the anti-coagulant is one of K3-EDTA, citrate and heparine.

21. Use according to any of the claims 15 -19, where the sample is of human origin.

22. Method for quantitative detecting the presence or absence of a target analyte in a sample consisting of less than 200 μl liquid, comprising the steps of:

a) providing an analyte containing liquid sample consisting of less than 200μl liquid; b) supplying the liquid sample to a first reaction part of a chamber, the chamber comprising a first reaction part and a second detection part, the two parts being physically separated such that liquid sample material cannot enter into contact with the second detection part; c) contacting the sample in the first reaction part of a chamber with an immobilisation matrix capable of capturing the analyte; d) immobilising the immobilisation matrix comprising the captured analyte; e) transferring the immobilisation matrix comprising the captured analyte to the second part of the chamber; f) remobilising and washing the immobilisation matrix comprising the captured analyte with a washing solution; g) immobilising the immobilisation matrix comprising the captured analyte; h) optionally, discarding the washing solution i) optionally, remobilising the immobilisation matrix comprising the captured analyte and repeating steps f) to h); j) transferring the immobilisation matrix comprising the captured anaiyte to the detector part of the second part of the chamber; and k) detecting the presence or absence of a target analyte using conventional detection means.

23. A method according to claim 22, where the first and second parts are separated by a collection chamber (fig. ref.).

24. A method according any of the claims 22-23 further comprising a step a") of contacting the analyte with a biological marker, capable of binding to the analyte.

25. A method according to claim 24, where the biological marker is an antibody e.g. coupled with an enzyme such as HRP or ALP.or biotin.

26. A method according any of the claims 24-25, where the step a') is performed prior to step e).

27. A method according to any of the claims 25-26, further comprising a step f) of contacting the immobilisation matrix comprising the captured analyte with a substance capable of reacting with the biological marker.

28. A method according to any of the claims 22-27, where the immobilisation matrix comprises magnetic material.

29. A method according to any of the claims 22-28, where the step e) is performed by moving a magnetic source along the external edge of the first reaction chamber toward the second detection chamber.

30. A method according to any of the claims 22-29, where the step e) is performed by moving a magnetic source along the external top edge of the first reaction chamber toward the second detection chamber.

31. A method according to any of the claims 28-30, where the magnetic material is selected from the group comprising magnetic particles, magnetic nanoparticles and superparamagnetic nanoparticles.

32. A method according to any of the claims 28-31 , where the magnetic material has an at least bimodal size distribution.

33. A method according to claim 32, where the magnetic material has a trimodal size distribution.

35. A method according to any of the claims 24-34, where the biological marker is one or more selected from mono-, oligo- and polyclonal antibodies, antigens, receptors, ligands, enzymes, proteins, peptides and nucleic acids.

36. A method according to any of the claims 24-35, where the biological marker is one or more selected from the group having the properties of light absorption, fluores- cence emission, phosphorescence emission, or luminescence emission .

37. A method according to any of the claims 24-36, where the immobilisation matrix is one and the same substance.

38. A method according to claim 22-37, where the conventional detection means are selected among surface acoustic wave (SAW) detectors, spectrophotometers, fluorometers, CCD sensor chip(s), CCOS sensor chip(s), PMT detector(s), or any suitable light detector.

39. A method according to any of the claims 22-38, where the sample is derived from blood.

40. A method according to claim 39, where the sample is serum.

41. A method according to claim 40, where the sample is plasma.

42. A method according to claim 41 , where the plasma is obtained by applying an anti coagulant to the blood.

43. A method according to claim 42, where the anti-coagulant is one of K3-EDTA, citrate and heparine.

44. A method according to any of the claims 22-43, where the sample is of human origin.

45. Kit of parts comprising a device according to any of the claims 1-14 and a magnetic material as defined on any of the claims 28 and 31-33.

46. Kit according to claim 46 for use according to any of the claims 15-21.