AT525192A1 - MICROFLUIDIC CHIP - Google Patents

Abstract

The invention relates to a microfluidic chip (1) for a measuring arrangement for the quantitative optical evaluation of a chemical reaction, comprising a sample carrier (2) with a carrier layer (3) and a sample layer (4), with the sample layer (4) on the analysis side (5) a plurality of test sections (7) are arranged at a distance from one another in a longitudinal direction (L) of the sample layer (4), and a first inlet (8) is arranged on the carrier layer (3), which is connected by means of microfluidics via a first channel (10). Test sections (7) is connected to a first receiving reservoir (12). It is proposed that the carrier layer (3) has a second inlet (9) which is separate from the first inlet (8) and which is connected to a second receiving reservoir (13) by means of microfluidics via a second channel (11) with test sections (7), wherein the first duct (10) has an analysis duct section which is designed to abut and run parallel to an analysis duct section of the second duct (11).

Description

The present invention relates to a microfluidic chip for a measuring arrangement for the quantitative optical evaluation of a chemical reaction

- a sample carrier with a carrier layer and a sample layer,

- wherein the carrier layer is arranged on the sample layer,

- Wherein the sample layer has an analysis side and, opposite this, a light exit side and

- a plurality of test sections being spaced apart from one another in a longitudinal direction of the sample layer on the analysis side of the sample layer,

-) and a first inlet is arranged on the carrier layer, which is connected to a first receiving reservoir by means of microfluidics via a first channel, and the sample layer is arranged with the analysis side on the carrier layer in such a way that a first row of test sections corresponds to the volume of the first channel is facing, according to the preamble of claim 1, and a method for the quantitative optical evaluation of a chemical reaction using a microfluidic chip according to the invention according to the preamble

of claim 4. PRIOR ART

Microfluidic chips per se are state of the art

already known.

AT 510750 B, which is understood here as the closest prior art, discloses a measuring arrangement for the quantitative optical evaluation of a chemical reaction, comprising a microfluidic chip which has an inlet for a sample

and a channel and a reservoir. The abandoned

chemical reaction emanating from the test section in question

electromagnetic signal, which is mostly in the visible wavelength range, serves as quantifiable evidence of a reactant in the sample. The electromagnetic

In this case, the signal is measured by photodetectors of a measuring arrangement into which the microfluidic chip has been inserted.

For this purpose, one is usually used in the longitudinal direction of the sample position

photodiode line running in the area of the test sections (also referred to as a photodiode array) is used, which forms a largely uninterrupted, strip-shaped measurement area that enables a one-dimensional, spatially resolved measurement of the signal. In particular, AT 510750 B proposes that the distance between the test sections and the photodetectors be less than 700um, so that at least 99.5 © of the electromagnetic radiation emanating from a test section is incident on a maximum of three photodetectors, so that the electromagnetic signal is as

can be precisely localized.

In order to accurately quantify reactants, the detector must be calibrated with a known amount of sample. For this purpose, the signal size of the

detector for a reactant with that of a standard

compared. Ideally, the comparison is made under constant analysis conditions, but this is sometimes difficult to achieve. Especially with decreasing concentration of the reactants and the associated weakness of the electromagnetic signal, constant analysis conditions and the current status of the measuring system must be taken into account. On the other hand, there is an increasing need for automated measurement arrangements in order to obtain measurement results quickly and to increase the sample throughput

accelerate.

OBJECT OF THE INVENTION

It is therefore an object of the invention to avoid the disadvantages of the prior art and to provide a microfluidic chip or a method with which it is possible to increase the accuracy of quantitative measurements and

to speed up the measurements at the same time.

PRESENTATION OF THE INVENTION

The object is achieved by a microfluidic chip for a measuring arrangement for the quantitative optical evaluation of a chemical reaction

- a sample carrier with a carrier layer and a sample layer,

- wherein the carrier layer is arranged on the sample layer,

- the sample position facing an analysis side and this

lying has a light exit side and

Channel section of the second channel faces.

The microfluidic chip according to the invention is suitable or provided for use in a suitable measuring arrangement for the quantitative optical evaluation of a chemical reaction. In order to be able to carry out a measurement, a drop or part of a drop of a sample is applied to the first inlet, the sample material being brought to the first receiving reservoir by the capillary effect of the first channel connected to this first inlet. The sample passes through the first row of spaced apart test sections on the sample layer, which have immobilized analytes, also referred to as scavenger molecules. The microfluidic chip generally has a number of test sections, which serve to ensure that the sample introduced into the test system by means of the inlet

Presence of a specific reactant with on the

Fluorescence properties are used for the measurement.

After the sample has passed through the first channel and any electromagnetic signals have been detected as evidence of chemical reactions, a corresponding standard can be applied to the second inlet. The standard passes through the second row of test sections arranged at a distance from one another on the sample layer, which in this application are identical to those of the first row. Since, according to the invention, the first channel has an analysis channel section that is adjacent to an analysis channel section of the second channel and runs parallel to it, the reactions of the sample and those of the standard take place in close proximity and can be detected by the same detector under approximately identical conditions Analysis conditions are measured. The comparative measurements using the standard can also be carried out very close in time to the analysis of the sample, which means that the analysis conditions can be assessed as constant and the current status of the measurement system is taken into account. In this way, the quality of the quantitative measurement can be decisively improved because it is possible to sample a sample almost simultaneously

and a related standard among practically the same

measuring conditions. The measurement of a drawn sample

together with a standard is of particular interest in the area of quality control in the chemical/pharmaceutical industry. In the case of quantitative measurements in particular, the limited shelf life of the reagents to be used must also be taken into account. Signal fluctuations due to limited durability and associated intensity losses in the intensity of the electromagnetic radiation can be reduced with a structure according to the invention and by knowing about

the concentration of the standard can be calculated.

However, the microfluidic chip according to the invention can also be used to measure two different samples. Different samples are understood to mean, for example, the samples from two different patients or two samples taken from one patient independently of one another or at different times. For this, after measuring the first sample, no standard is applied to the second inlet, but a second sample. The advantageous arrangement according to the invention with two inlets enables a faster throughput than in conventional test systems because two different samples can be tested in quick succession. This is particularly advantageous when the largest possible contingent of samples has to be analyzed in the shortest possible time. In contrast to the known prior art, it is also possible to avoid contamination by applying the two

prevent sampling through the same inlet.

Of course, it is also possible to give the same test to both inlets. In this way, either the same sample can be measured twice using the same analytes, increasing the accuracy of the measurement, or different ones will be used in the first and second series of test sections

Test sections used. In general, the test sections

7127

which extend along the first and the second channel, either have the same sequence of immobilized capture molecules, which is recommended when using a standard or when measuring two different samples. Alternatively, the test sections along the first channel can also have completely different immobilized capture molecules than the test sections along the second channel, which makes it possible to determine even more different parameters or biomarkers. However, this will only make sense if the same sample is applied to the first and second inlet. In each of these cases, however, the test sections are arranged - preferably in such a way that the test sections of a row are spaced apart from one another as seen in the longitudinal direction of the sample layer, and the test sections of the first and second row in

Seen in the transverse direction are each arranged in alignment.

The usual human or animal samples such as blood, saliva or sputum or also samples taken during or after a manufacturing process in the chemical/pharmaceutical industry come into consideration as the sample to be measured with the aid of the microfluidic chip. Of course, it cannot be ruled out that other samples will also be measured

be used.

The microchip according to the invention can therefore also be used in particular in connection with the detection of viral diseases or allergies. Of course, other applications are not excluded. Depending on the area of application, the analytes used, i.e. capture molecules, must of course be adapted to the parameters to be measured or

Biomarkers are adjusted.

The test sections can, for example, contain immobilized capture molecules in the form of antibodies as analytes for generating a

include chemical reaction to particular antigen testing

to be able to carry out. The use of antibodies as capture molecules in the chip according to the invention enables a

rapid parameter determination with regard to antigens, whose

Education can be triggered by viral infections, among other things

be able. Due to the advantageous arrangement of the invention with

Having at least two inlets allows faster throughput than conventional test systems because testing of two different samples is possible. This is particularly advantageous when a possible in the shortest possible time

large contingent of samples to be analyzed.

The channels usually have a length of 30-50 mm, a width of 1-4 mm and a height of 10-200 μm. The channels or the carrier layer, which comprises the channels, can be produced cost-effectively by injection molding of the carrier layer. The channels usually have a very small volume, so that the consumption of sample chemicals or sample material is minimized, which in turn is advantageous for the efficiency and acceptance of the method. A configuration of the channel with a length of 40 mm, a width of 2 mm and a height of 100 μm is preferred. Furthermore, it must be ensured that the cross section of the channels is designed in such a way that a capillary effect of the channels is ensured. According to the invention, the first channel also has an analysis channel section, which is designed to rest against an analysis channel section of the second channel and to run parallel to it. "Abutting" here means that the analysis channel section of the first channel and the analysis channel section of the second channel must be at least so close together that they pass through the measuring range of the same photodetector, in particular the measuring range of the same photodiode line (also referred to as a photodiode array) , as they are already known in the field of quantitative analysis of chemical reactions.

Preferably, the analysis channel portion of the first

Channel and the analysis channel section of the second channel as close together as possible, as far as the production technology while ensuring a structurally stable separation of the

both canal sections is possible.

One embodiment of the invention provides that the chip has 5 to 15 test sections in each analysis channel section. When using, for example, a total of 20 different test sections in both analysis channel sections, 20 different parameters or analytes can be tested. The use of 20 different parameters or biomarkers will be used and will be advantageous in particular when the microfluidic chip is used to detect the presence of specific allergies. Of course, it cannot be ruled out that 20 different analytes can also be found in one

be used in another context.

Furthermore, it is proposed that the first inlet and the second inlet are arranged one behind the other, viewed in the longitudinal direction of the sample layer. This measure enables compact structural designs in connection with the measurement arrangement provided for the chip according to the invention, which is known in principle from AT 510750 B, as explained below

will be executed.

The object is further achieved by a method for the quantitative optical evaluation of a chemical reaction using a microfluidic chip according to the invention with a measuring arrangement having an optical detector, comprising the steps that follow one another in terms of time

- applying a sample to the first inlet of the microfluidic chip, - transferring the sample through the first channel to

Test sections using microfluidics to, where appropriate

to generate chemical reactions, — detection of the reactions with the optical detector, —- applying the same sample or a different sample or a standard to the second inlet of the microfluidic chip,

- transferring the same sample or the other sample or standard through the second channel to test sections by means of microfluidics to generate chemical reactions if necessary,

—- detection of the reactions with the optical detector, and — quantitative evaluation of the reactions with the optical detector

detected reactions.

For this purpose, the microfluidic chip is introduced into a suitable measuring device and a sample is applied to the first inlet and, depending on the requirement, the same or another sample or a standard is applied to the second inlet. Due to the capillary action of the channels, the samples are guided through the channels and, if the corresponding parameter/biomarker is present, this is bound by the corresponding analyte in the test section. Depending on the requirements, different reagents can also be added automatically by the measuring device, if necessary, which are required to achieve the desired chemical reactions or to terminate them. For example, after measuring a first sample in the first channel and before measuring a second sample in the second channel, it is possible to run a washing solution through the first channel in order to stop any chemical reaction in the test sections of the first row and thus eliminate interfering signals to avoid when measuring the second sample. In order to ensure that the samples and reagents are applied in the correct order, several actuating elements can also be present, via which the reagents or the sample to be analyzed are applied in the correct order and in

the specified amount can be delivered. Furthermore, a

Control module can be provided, which in operative connection with the actuating elements automatically and in the correct order delivers the samples and any reagents. In particular, the control module can also be designed to evaluate the measured signals of the photodetector, to process them accordingly and to connect them to a communication connection

to provide.

In a preferred embodiment of the method according to the invention it is provided that the chemical reaction is a bio- or chemiluminescence reaction in order to detect a positive result particularly well and in which

to be able to prove consequences.

Of course, it is not excluded that a microfluidic chip according to the invention has more than two inlets and associated channels and receiving reservoirs,

for example three, four or five.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be explained in more detail using an exemplary embodiment. The drawings are exemplary and are intended to illustrate the idea of the invention, but in no way

constrict or even finalize.

It shows:

1 is a perspective view of one according to the invention

microfluidic chips

Fig. 2 is a perspective view of a carrier layer of a

microfluidic chip according to the invention

3 is a plan view of one according to the invention

microfluidic chips

WAYS TO CARRY OUT THE INVENTION

1 shows a perspective view of a microfluidic chip 1 according to the invention. The microfluidic chip 1 preferably has a length of 75 mm and a width of 25 mm and a thickness of approximately 1.5 mm. In addition, the chip 1 is preferably designed to be completely transparent. Of course, it cannot be ruled out that

the chip 1 has other dimensions and partially

is formed intransparent.

The microfluidic chip 1 comprises a sample carrier 2 with a carrier layer 3 and a sample layer 4 . The carrier layer 3 is arranged on the sample layer 4 . The sample position 4 has an analysis side 5 and a light exit side 6 lying opposite thereto. The analysis side 5 is required in order to be able to analyze an applied sample, while the light exit side 6 is required at the same time, when chemical reactions occur, optical effects generated by the chemical reaction also with the help of a

suitable measuring device to be able to detect. For surveying

is the microfluidic chip 1 in a measuring arrangement (in the

Fig. 1-3 not shown) inserted.

The microfluidic chip 1 also includes a first inlet 8 and a second inlet 9 which is separate from the first inlet 8. The first inlet 8 is connected to a first channel 10, which has a volume, and to a first receiving reservoir 12. The second inlet 9 is connected to a second channel 11 having a volume and a second receiving reservoir 13 . The first and second channel 10 , 11 are formed by the sample layer 4 and the carrier layer 3 . The inlets 8 , 9 are located on the backing layer 3 , forming recesses in the backing layer 3 . The sample layer 4 has a plurality of test sections 7 on its analysis side 5, the test sections 7 being arranged in such a way that they correspond to the volumes of the channels

10:11 facing, so that the test with the on the

13

Test sections 7 immobilized capture molecules in contact

can come. By capillary action, the sample after the

Applied to the inlets 8.9 conveyed through the channels 10.11, with possible parameters or biomarkers contained in the sample being able to react with the analytes of the test sections 7. The sample solution is then stored in the receiving reservoir 12,13. Further required reagents can then be added via the inlets 8.9 at the time intervals required in each case in order to obtain desired bio- or chemiluminescent reactions or to terminate them. These reagents are then also stored in the receiving reservoir 12,13. 7 The volumes of the samples and the other reagents are of course corresponding to the recording volume of the

Recording reservoirs 12.13 selected or adjusted.

In order to be able to generate a chemical reaction at all and thus be able to analyze a sample, the microfluidic chip according to the invention has test sections 7, in the present case 18 test sections 7, which are arranged spaced apart from one another along a longitudinal direction L of the sample layer 4. In the present case, antibodies are immobilized as so-called capture molecules on the test sections 7, with each test section having a different antibody as a capture molecule, so that it is possible in a sample 18

to measure different parameters.

The microfluidic chip 1 according to the embodiment of FIG. 1 further includes a connecting element 14, whereby the microfluidic chip 1 can be detachably connected to a suitable measuring arrangement in order to measure the microfluidic chip 1 or the samples applied therein

to allow.

Fig. 2 shows only the base layer 3 of the embodiment

of the microfluidic chip 1 according to the invention as shown in Fig.

1. The carrier layer 3 is part of the sample carrier 2. The carrier layer 3 includes the first and second inlet 8.9, the first and second channel 10.11 and the first and second receiving reservoir 12.13, the channels 10.11 and the Recording reservoirs 12,13 are formed by the carrier layer 3. When the support sheet 3 is placed on a corresponding sample sheet 4, the support sheet 3 and the sample sheet 4 sandwich the channels 10,11 with the test portions 7 of the sample sheet 4 located on the analysis side 6 of the sample sheet 4 in contact with the

Volumes of channels 10,11 come.

3 shows a top view of the embodiment of the microfluidic chip according to the invention as shown in FIG. 1. FIG. 9 out. Furthermore, the two separate channels 10,11 can be seen. The first channel 10 is connected to the first inlet 8 and opens into the first receiving reservoir 12. The second channel 11 is connected to the second inlet 9 and opens into the second receiving reservoir 13. Furthermore, FIG microfluidic chip 1 with a

suitable measuring device can be detachably connected.

Fig. 3 also shows that the test sections 7 are arranged in two rows, namely in the form of a first row of test sections 7a along the analysis channel section of the first channel 10, and in the form of a second row of test sections 7b along the analysis channel section of the second channel 11. The first row of test sections 7a faces the volume of the analysis channel section of the first channel 10 and the second row of test sections 75 faces the volume of the analysis channel section of the second channel 11. The analysis channel section of the first channel 10 is at the

Analysis channel section of the second channel 11 adjacent and

running parallel to it. After the microfluidic chip 1 has been inserted into a measuring arrangement, the test sections 7 are in the strip-shaped detection area of FIG

Photodetectors, as will be explained in more detail below.

As has already been mentioned, the chip according to the invention can be used with a measurement arrangement as is known in principle from AT 510750 B. In this case, the sample carrier 2 can be detachably arranged in a receiving device of the measuring arrangement, so that the light exit side 6 of the sample layer 4 is arranged facing a photodetector. The photodetector is in turn arranged in a base body, with the photodetector being covered by a transparent cover layer. The receiving device is designed, for example, in such a way that the sample carrier 2 is placed in a stationary part of the receiving device and is held fixed by a second, movable and/or foldable part of the receiving device. The photodetector of the measuring arrangement is arranged in the base body in such a way that the test sections 7 are arranged along the channels 10, 11 with their light exit side above the photodetector. If the hinged part is pivoted into the measuring position, the interior space, in particular the sample carrier 2 and the

Photodetector, Lllight-tightly sealed from the environment.

The sample carrier 2 has the inlets 8, 9 into which the sample to be analyzed is released, which is automatically moved from the respective inlet 8, 9 to the receiving reservoir 12, 13 assigned to it due to the dimensioning of the channels 10, 11 and the microfluidics . However, when sample material is dispensed at the inlet 8, 9, care must be taken that on the one hand the quantity to be dispensed is adhered to as precisely as possible and on the other hand a sequence in which sample chemistry is dispensed is adhered to. Furthermore, a feeding device is provided in the foldable part

respective inlet 8, 9 for liquid-tight delivery of the

Contacted sample material and also ensures the light-tight closure of the sample carrier 2 from the environment. Thus, the sample carrier 2 can be inserted into the receiving device of the measuring arrangement and the foldable part can then be closed without sample material or sample chemistry already being in the microfluidic, which ensures that no chemical reaction is triggered prematurely in the test sections 7. Only when the sample carrier 2 is closed and after a light-tight seal has been reliably produced are the reagents or the sample to be analyzed released at the feed device and forwarded by it to the respective inlet 8 , 9 of the sample carrier 2 . Since additional reagents can also be required to carry out the sample analysis, the measuring arrangement can also have a dispensing device for reagents. The dispensing device preferably comprises an actuating element and a removable depot which can be coupled and which is designed, for example, as a blister and has a number of closed containers in which reagents are arranged. In the case of a blister as a depot, after actuating the actuating element, the seal of the reagent chamber is broken and the reagent is transferred to the respective inlet 8, 9 via the feed device. In order to ensure that the sample is delivered in the correct order, several actuating elements can also be present, via which the reagents or the sample to be analyzed can be delivered in the correct order and in the specified quantity. The depot can also specify an activation direction, for example in that the depot is rotatably accommodated in the dispensing device and is rotated further manually or automatically after each reagent dispensing. Furthermore, a control module can be provided which, in operative connection with the actuating elements, dispenses the reagents automatically and in the correct sequence. The control module can also be designed in particular to

Evaluate measured signals of the photodetector, prepare them accordingly and make them available at a communication port. This communication connection is preferably formed by a USB communication connection, although further wired or wireless communication connections are possible

from the field of data transmission are possible.

The invention, overcoming the disadvantages of the prior art, thus provides a microfluidic chip with which it is possible to increase the accuracy of quantitative measurements

and speed up the measurements at the same time.

REFERENCE LIST

1 microfluidic chip 2 sample carrier 3 carrier layer 4 sample layer 5 analysis side 6 light exit side 7 test sections 8 first inlet 9 second inlet 10 first channel 11 second channel 12 first receiving reservoir 13 second receiving reservoir 14 connecting element L longitudinal direction of the sample layer

Claims (5)

Patent Claims: 1. Microfluidic chip (1) for a measuring arrangement for the quantitative optical evaluation of a chemical reaction comprising - a sample carrier (2) with a carrier layer (3) and a sample layer (4), - wherein the carrier layer (3) is arranged on the sample layer (4), - wherein the sample layer (4) has an analysis side (5) and a light exit side (6) lying opposite and -- wherein a plurality of test sections (7) are arranged at a distance from one another in a longitudinal direction (L) of the sample layer (4) on the analysis side (5) of the sample layer (4), -) and on the carrier layer (3) a first inlet (8) is arranged, which is connected to a first receiving reservoir (12) via a first channel (10) by means of microfluidics, and the sample layer (4) with the analysis side (5) is arranged on the support layer (3) in such a way that a first row of test sections (7a) faces the volume of the first channel (10), characterized in that the support layer (3) has a second inlet ( 9) which is connected to a second receiving reservoir (13) via a second channel (11) by means of microfluidics, the first channel (10) having an analysis channel section which abuts an analysis channel section of the second channel (11). and running parallel to it and the first row of test sections (7a) faces the volume of the analysis channel section of the first channel (10) and a second row of test sections (7b) faces the volume of the analysis Channel section of the second channel (11) faces. 2. Microfluidic chip (1) according to claim 1, characterized in that the chip (1) in each analysis Channel section has 5 to 15 test sections (7). 3. Microfluidic chip (1) according to any one of claims 1 or 2, characterized in that the first inlet (8) and the second inlet (9) in the longitudinal direction (L) of Sample layer (4) are seen arranged one behind the other. 4. A method for the quantitative optical evaluation of a chemical reaction using a microfluidic chip (1) according to any one of claims 1 to 3 with a measuring arrangement having an optical detector, comprising the chronologically sequential steps -- applying a sample (19) in the first Inlet (8) of the microfluidic chip (1), - transferring the sample through the first channel (10) to test sections (7) by means of microfluidics to generate chemical reactions if necessary, -- detecting the reactions with the optical detector, --- Applying the same sample or a different sample or standard to the second inlet (9) of the microfluidic chip (1), —- transfer the same sample or the different sample or the standard through the second channel (11) to test sections (7) by means of microfluidics in order to generate chemical reactions if necessary, —- detection of the reactions with the optical detector, and — quantitative evaluation of the reactions with the optical detector detected reactions. 5. The method according to claim 4, characterized in that it is a biological or in the reaction Chemiluminescence reaction is.