HK1130901B - Method and apparatus for analyzing a dry chemical test element - Google Patents

Description

Method and device for analyzing dry chemical test elements

Technical Field

The invention relates to a method and a device for analyzing dry chemical test elements, in particular immunoassay test elements.

Background

The present technique is used to assay (assay) one or more analytes loaded with dry chemical test elements. To this end, a plurality of assay regions, such as strips, circles or squares, are formed on the test element, where one or more analytes (e.g., US6,707,554B1) accumulate depending on the volume of liquid sample required for the assay. Typically, the analyte is directly labeled for subsequent optical analysis of the dry chemical test element. The preparation of the dry chemical test element may also include washing or rinsing with a buffer solution, diluent or wash solution. Finally, the dry chemical test element can be analyzed by optical scanning to determine the presence of one or more specific analytes in the assay region of the test element.

During optical scanning, a measuring beam generated by scanning the assay region may be detected by a detector after leaving the assay region. A measuring beam is generated by applying a test beam, a portion of which is generated using a suitable monochromatic or polychromatic light source, carrying the photoactive substance to be measured in the assay area. At the assay region, light from the test beam interacts with the optically active material, causing a corresponding change in the optical properties of the test beam as a measuring beam to exit the assay region. When a test beam is applied, transmission, reflection or fluorescence can be used to analyze the optical properties of the measuring beam. The measuring beam may also be based on the luminescence of the optically active substance of the assay region.

The intensity of the measuring light as it leaves the respective assay region may vary from assay region to assay region. For example, the fluorescence generated by the test beam at the respective assay areas may be emitted at different intensities, which may be indicative of, for example, the concentration of the analyte to be detected. The intensity of the emitted measured light is particularly relevant for the light absorption range of the assay region under observation. Such as fluorescence assays, whose range is particularly relevant to the concentration of fluorescent molecules.

During optical scanning of the dry chemical test element, the measuring beam is detected by, for example, the test element and the detector device, or the test beam and the light source can be replaced relative to each other, so that one assay area after another is optically analyzed. According to known optical scanning procedures, certain scanning parameters are set before starting scanning, and then scanning is started. A constant scanning speed and exposure time of the detector arrangement is usually set. If measuring light of different intensities is emitted from the assay region on the dry chemical test element, there arises a problem that the intensity of the area measuring light is low, generally corresponding to a low concentration of the analyte to be measured, and in some cases, the scanning speed is too high to actually collect a detection signal suitable for the analyte. In other areas with a larger concentration of analyte, the light intensity of the measuring beam leaving the assay area is too high to overload the detector arrangement at the current scanning speed.

Disclosure of Invention

The object of the invention is to provide a method and a device for analyzing dry chemical test elements, in which an optimized analysis can be achieved by means of optical scanning even when the assay areas of the test elements which carry the photoactive substances to be tested have different optical activities.

The object of the invention is achieved according to the invention by a method for analyzing a dry chemical test element according to independent claim 1 and by an apparatus for analyzing a dry chemical test element according to independent claim 12. Methods and apparatus for conducting diagnostic drug tests are also provided. Preferred embodiments of the invention form the subject matter of the dependent claims.

According to one aspect of the present invention, there is provided a method of analysing a dry chemical test element, in particular an immunological test element, by means of optical scanning, whereby a measuring beam leaves an assay region of the test element, said assay region carrying one or more immobilized optically active substances, and each measuring light intensity is detected by means of a detector device, said method comprising the steps of: during optical scanning of the first assay region, a measuring light beam having a first measuring light intensity leaves the first assay region, a scanning parameter is selected in accordance with a first setting of the scanning parameter, the operating range of the detector arrangement and a first quantity of light of the measuring light beam impinging on the detector arrangement are adjusted relative to each other, and during optical scanning of the second assay region, a measuring light beam having a second measuring light intensity, which differs from the first measuring light intensity, leaves the second assay region, a scanning parameter is selected in accordance with a second setting of the scanning parameter, which differs from the first setting of the scanning parameter, the operating range of the detector arrangement and a second quantity of light of the measuring light beam impinging on the detector arrangement are adjusted relative to each other.

According to another aspect of the present invention, there is provided a device for analyzing dry chemical test elements, in particular immunological test elements, by optical scanning, the device comprising: a holder for holding a dry chemical test element for optical scanning analysis, a detector device for detecting a measuring beam leaving an assay area, said assay area carrying one or more immobilized optically active substances and having a corresponding measured light intensity, and a control device for controlling the optical scanning of the dry chemical test element as follows: during optical scanning of the first assay region, a measuring light beam having a first measuring light intensity leaves the first assay region, a scanning parameter is selected in accordance with a first setting of the scanning parameter, the operating range of the detector arrangement and a first quantity of light of the measuring light beam impinging on the detector arrangement are adjusted relative to each other, and during optical scanning of the second assay region, a measuring light beam having a second measuring light intensity, which differs from the first measuring light intensity, leaves the second assay region, a scanning parameter is selected in accordance with a second setting of the scanning parameter, which differs from the first setting of the scanning parameter, the operating range of the detector arrangement and a second quantity of light of the measuring light beam impinging on the detector arrangement are adjusted relative to each other.

According to the invention, during the scanning of the analytical dry chemical test element, the optical scanning properties of the measuring system used, in particular the optical element, can be adjusted independently to the photoactivity of the assay area being analyzed. The amount of light of the measuring beam irradiated to the detector device is controlled so that the detector always operates in a predetermined operating range. The operating range is predefined for the detection means, such as a two-dimensional arrangement of light-emitting diodes, light-emitting diodes or photomultipliers, and can be selectively arranged by suitable electrical wiring of the detector. The operating range of the detector device, which is generally the range in which the electrical signal generated by the detector is linearly related to the amount of light irradiated, shows a clear and reproducible behavior. If the amount of light striking the detector surface is outside the detector operating range, i.e., dynamic range, the output signal is typically not observed because the amount of light is too low or the detector is overloaded resulting in saturation or non-linearity. In this case, even if the electrical output signal can be distinguished from the detector noise, it is still difficult or even impossible to use for evaluation to analyze the assay. The non-linear range may also be designated as the operating range of the detector device if it is a reproducible response function of the known assay device and allows evaluation of the generated output electrical signal.

The measuring beam can be detected in the form of, inter alia, a transmitted beam, a reflected beam, a scattered beam or a transmitted beam. The choice of which optical property or properties to analyze may be determined by specifically considering the properties of the dry chemical test element containing the analyte to be assayed. The transmitted, reflected or scattered light beam is generated by a test light beam applied to the assay area, which interacts with the assay area containing the immobilized optically active substance, resulting from a correspondingly varying measuring light beam. However, emission beams in the form of fluorescence and phosphorescence may also be generated in such optical scanning. In addition, the optical scanning may include detection of an emitted light beam from the assay region due in part to bioluminescence, chemiluminescence, or electrochemiluminescence. In the case of bioluminescence or chemiluminescence, a substance is added and the emission of a light beam in the form of luminescence (luminescence) is triggered by the optically active substance of the assay region. Instead, electrochemical luminescence is based on supplying electrical energy to the assay region of the dry chemical test element to cause the photoactive material to emit light. Suitable means for providing electrical energy to the assay region, such as one or more electrodes, are given in embodiments of the method.

The photoactive material is generated by the reaction of one or more reagents immobilized on the test element, where the reaction may be a binding reaction or a chemical reaction. The result of the reaction during the preparation of the test element for the optical scanning process is that an optically active substance is produced which has properties useful for optical scanning. The binding reaction may be, for example, an immunological binding reaction or a hybridization reaction. This reaction or chemical reaction may occur multiple times. One or more reagents immobilized on the test element may be indirectly labeled by one or more binding reactions. The presence of one or more reagents may also prevent binding of the labelled reagent.

One or more measures (measures) can be provided for the transition between the scanning parameters according to the first setting of the scanning parameters and the scanning parameters according to the second setting of the scanning parameters, so that the amount of light of the measuring beam impinging on the detector means is correspondingly set to the working range of the detector. These measures also include, for example, inserting or removing filters in the path of the measuring beam to the detection device. The use of a diaphragm (diaphragm) also provides an example.

In principle, any measure can be used to adjust the amount of light of the measuring beam impinging on the detector device in accordance with the working range of the detector device. In an embodiment it is even possible to change the working range by using the electrical wiring of the detector device, so that again a match between the amount of light irradiated and the working range can be achieved. By way of example, in this connection the amplification factor can be varied. The adjustment of the working range of the detector device may alternatively or additionally affect the amount of light impinging on the detector device. The adjustment of the working range of the detector means also becomes part of the scan parameters of the associated scanning process.

More preferred embodiments of the present invention provide one or more of the following variables selected from the set of scan parameters set as follows: scanning speed, exposure time, test light intensity of the test beam, amplification factor of the detector, and power to the assay region. The scanning speed refers to the relative movement speed of the dry chemical test element with the assay region thereon on the one hand and the scanning device, in particular comprising the detector device, on the other hand. Additionally or alternatively, where a test beam is used, the speed at which the test beam passes through the assay region may be set. By these measures, for each assay area, an associated scanning time is obtained during which the measuring beam is detected by the detector device for the respective assay area. If the measured light intensity of the measuring beam leaving the assay area is relatively low, typically indicating a low analyte concentration, the scanning speed may be selected correspondingly low so that a sufficient amount of measuring beam light impinges on the detector means. Conversely, the scanning speed may be increased if it is determined that the measured light intensity of the different assay areas is too strong. The exposure time refers to the time during which the detector means detects the measuring beam for the assay area. Which is affected first by the scanning speed. In addition, the optical element that exposes or covers the detector surface of the detector device may be switched on or off for a predetermined period of time or for a plurality of predetermined periods of time. Here, an adjustable diaphragm may be provided. However, the intensity of the test beam, which is applied to the dry chemical test element for analysis, typically affects the intensity of the measurement beam. This scan parameter may also be adjusted.

In a preferred embodiment of the invention, at least one of the scan parameters is constant for the first and second settings of the scan parameter. The smaller the number of scan parameters that have to be changed when changing between the first and second scan parameters, the more rapidly the change occurs.

In a preferred embodiment of the present invention, the change of the scan parameter according to the first setting of the scan parameter to the scan parameter according to the second setting of the scan parameter is performed during the continuous scan of the dry chemical test element.

Advantageously, the invention is further developed in that the change of the scanning parameters according to the first setting of the scanning parameters to the second setting of the scanning parameters is a function of measurement information derived from a pre-scanning process performed beforehand. The pre-scan process performed in advance may provide information about the photoactivity of the individual assay regions of the dry chemical test element, which is an absolute or relative measurement parameter. Based on this information, the assay region scan parameter settings can be set so that changes can be made in the optical scanning device accordingly. The pre-scan process may be a fast scan. Additionally or alternatively, the pre-scanning process is performed under a condition of lower resolution than that set for the subsequent main scanning. For the pre-scanning process, it is not necessary to use the actual dry chemical test element to be analyzed, and a model test element or a standard test element similar to the assay area configuration may be used.

In a preferred embodiment of the present invention, the change in the scan parameter from the first setting of the scan parameter to the second setting of the scan parameter is a function of current measurement information derived from current measurements of the optical scanning process of the dry chemical test element. Even if the scanning behavior is preset, changes between the scanning parameter settings can be triggered immediately or on the spot during the scanning process.

A further development of the invention is that the change from the scanning parameter of the first setting to the scanning parameter of the second setting of the scanning parameter occurs a plurality of times during the optical scanning of the dry chemical test element. The change between the scan parameter settings can be automatically performed a plurality of times according to preset control parameters. However, additionally or alternatively, the current measurement information obtained during the scanning process may also cause multiple changes.

A further preferred development of the invention is that the first assay area is optically scanned again after an optical scanning with a scanning parameter according to a first setting of the scanning parameter, with a scanning parameter according to a second setting of the scanning parameter. The second optical scan of the first assay zone may be performed immediately prior to the optical scan of the subsequent assay zone. However, it is also possible to perform a second optical scan of the first assay area after a complete one scan of the dry chemical test element. In this case, it is generally necessary to return to the first assay zone. If no signal or insufficient signal is present on the detector means for analysis, using the first set of scanning parameters, a second optical scan of the first assay area may be performed. The first assay area is then analyzed again by changing the settings of the scanning parameters.

In an advantageous embodiment of the invention, the test light application zones assigned to the respective test fields do not overlap during the optical scanning of the test fields. The test light application zone serves as an area on the dry chemical test element through which the test light passes during an optical scan (inconjunctionwith) associated with the relevant assay zone. In this regard, embodiments provide for bringing the test light application zones into close proximity with one another so that there are no areas therebetween that are not exposed to the test light.

In an advantageous embodiment of the invention, the first amount of light is selected to lie within a first sub-range of the working range and the second amount of light is selected to lie within a second sub-range of the working range, different from the first sub-range. More preferably, the first and second subranges are lower and upper subranges of the operating range. In this way the working range and dynamic range of the detector means are utilized to the fullest extent.

Preferably, an improvement of the invention consists in that a plurality of identical assay areas are optically scanned at a scanning position and detected in a two-dimensional resolved (resolved) manner. This embodiment uses a detector arrangement that allows a two-dimensional resolved test beam to impinge on the detector surface. By means of an embodiment of the method described, a plurality of assay areas can be measured transversely to the scanning direction.

In various embodiments of the method described, the image information obtained during the optical scanning process can be processed according to a so-called integrating (tacking) process. In this process, the individual images are combined to form a full image, and multiple occurrences of image information, such as overlay, may be eliminated. Integration may be achieved by suitable software obtained by different methods.

With regard to embodiments of the device for analyzing dry chemical test elements according to the invention, the description is given in connection with the associated method.

Drawings

The present invention will be described in detail with reference to the preferred embodiments and the accompanying drawings, wherein:

FIG. 1 is a schematic view of an apparatus for analyzing a dry chemical test element,

figure 2 shows an example of a dry chemical test element,

figure 3 shows a schematic view of the scanning process,

FIG. 4 is a schematic view of a dry chemical test element having a plurality of assay regions arranged in a lateral direction of a scanning device, an

FIG. 5 is a schematic diagram of a scanning process in which the assay region of the dry chemical test element is optically scanned again after a first scanning process.

Detailed Description

Fig. 1 shows a schematic view of an apparatus for analyzing a dry chemical test element 1 by optical scanning. Optical analysis of a test element 1 placed on a carrier 2, which serves in particular as a holder for the test element 1, can provide analytical detection of one or more optically active substances in the assay area of the test element 1, in particular for medical diagnostic analysis. The photoactive substance is generated by the reaction of one or more reagents immobilized on the test element 1, where the reaction may be a binding reaction or a chemical reaction. As a result of the reactions that take place during the preparation of the test elements for the optical scanning process, optically active substances are produced which have properties useful for optical scanning. The binding reaction may be, for example, an immunological binding reaction or a hybridization reaction. This reaction or chemical reaction may occur multiple times. One or more reagents immobilized on the test element 1 can be indirectly labeled by one or more binding reactions. The presence of one or more reagents prevents the binding of the labelled reagent.

In this embodiment, during the optical scanning process, a test beam generated by the test light source 3 is applied to the dry chemical test element 1. The measuring beam leaving the dry chemical test element 1 can be detected by the detector device 4. During optical analysis, relative movement between the dry chemical test element 1 and one or more optical elements (in particular the test light source 3 or the detector device 4) can occur. A control device 5 coupled to the detector device 4 and the test light source 3 for setting scanning parameters during the optical scanning, in any case for different assay areas on the dry chemical test element 1. For this purpose, the control means 5 are coupled to a movement unit 6 for generating a relative movement during the scanning.

By means of the control device 5, the scanning parameters are set in accordance with the different assay areas of the dry chemical test element 1, the amount of light received by the detector device 4 and the working range of the detector device 4 being adjusted relative to each other. The scanning parameters set include, in particular, the scanning speed and the exposure time of the detector device 4, the intensity of the test beam and the setting of the amplification factor of the detector device.

Fig. 2 shows a schematic view of a dry chemical test element, with an assay area 21 formed on a substrate 20, which may be designed as a membrane. The photoactive material used in the assay is "trapped" (i.e., immobilized) in a plurality of assay regions 21. Binding of the photoactive material of the assay region 21 occurs, particularly by antibodies that react with the photoactive labeled or tagged molecules. The intensity of the measuring beam exiting the plurality of assay regions 21 during scanning is an extent (indicator) of the presence of one or more optically active substances in one or more of the assay regions 21.

FIG. 3 is a schematic diagram of a scanning process in which two test beam application zones 31, 32 are provided on a dry chemical test element 30. Which are areas on dry chemical test element 30 through which a test beam passes while scanning the respective associated assay areas. It can be seen that the test beam application zones 31, 32 are adjacent to each other and they do not overlap. According to one embodiment, the settings of the scanning parameters of the two test beam application areas 31, 32 may be different in the optical scanning, e.g. different scanning speeds.

Fig. 4 shows a schematic representation of a dry chemical test element 40, the test field 41 of which extends not only in the scanning direction 42 but also in its transverse direction (transversely). During optical scanning of the dry chemical test element 40, spatial resolution in a direction transverse to the scanning direction 42 may be achieved if appropriate detector means, such as a two-dimensional diode array, are present. The advantage is that the overlapping test fields 41 belong to the "same signal class", i.e. they emit measuring light beams of the same or similar intensity, which can also be analyzed with the same scanning parameter settings.

Fig. 5 is a schematic view of a scanning process, in which after a first scan, the assay region 51 on the dry chemical test element 50 is optically scanned again, and then a subsequent assay region 52 is scanned. In this way, during scanning of assay region 51, it is possible to function during the optical scanning process if it is determined that the initial received light intensity is not sufficient to produce a signal suitable for analysis on the detector device.

The above description relates to optical scanning using a test beam applied to an assay region, in which an optically active substance to be analysed is present in a fixed form, thereby generating a measuring beam, which may be, in particular, a transmitted beam, a reflected beam, or an emitted beam. Additionally or alternatively, for analyzing the dry chemical test element 1, a measuring beam is generated, which measuring beam can be detected essentially on the basis of bioluminescence (bioluminescence), chemiluminescence or electrochemiluminescence. The scan parameters may be set by the above description.

The features of the invention disclosed in the above description, the claims and the drawings may be of importance for the implementation of the various embodiments of the invention either individually or in combination.

Claims (27)

1. A method of analysing a dry chemical test element, wherein the dry chemical test element is analysed by means of optical scanning, whereby a measuring beam leaves an assay region (21; 41; 51) of the test element (1; 20; 30; 50), which assay region (21; 41; 51) carries one or more immobilized optically active substances, and each measuring light intensity is detected by means of a detector device (4), the method comprising the steps of:

during optical scanning of the first assay region, a measuring light beam having a first measuring light intensity leaves the first assay region, scanning parameters are selected in accordance with a first setting of the scanning parameters, the operating range of the detector device (4) and a first light quantity of the measuring light beam impinging on the detector device (4) are adjusted relative to one another, and

during optical scanning of the second assay region, a measuring light beam having a second measuring light intensity differing from the first measuring light intensity leaves the second assay region, the scanning parameter is selected on the basis of a second setting of the scanning parameter differing from the first setting of the scanning parameter, and the operating range of the detector device (4) and a second light quantity of the measuring light beam impinging on the detector device (4) are adjusted relative to each other.

2. The method of claim 1, wherein the one or more variables set as scan parameters are selected from the following group of variables: scanning speed, exposure time, test light intensity of the test light beam, amplification factor of the detector device (4) and power supply of the assay area (21; 41; 51).

3. A method as claimed in claim 1 or 2, characterized in that at least one of the first and second settings of the scanning parameter is constant.

4. Method according to claim 1 or 2, characterized in that during the continuous scanning of the dry chemical test element (1; 20; 30; 50), the scan parameter set according to the first scan parameter is changed into the scan parameter set according to the second scan parameter.

5. A method according to claim 1 or 2, wherein the change of the scan parameter according to the first setting of the scan parameter to the scan parameter according to the second setting of the scan parameter is a function of measurement information derived from a pre-scan process performed in advance.

6. The method according to claim 1 or 2, characterized in that the change of the scan parameter according to the first setting of the scan parameter to the scan parameter according to the second setting of the scan parameter is a function of current measurement information derived from current measurements of the optical scanning process of the dry chemical test element (1; 20; 30; 50).

7. Method according to claim 1 or 2, characterized in that during the optical scanning of the dry chemical test element (1; 20; 30; 50) a change between a scanning parameter according to a first setting of the scanning parameter and a scanning parameter according to a second setting of the scanning parameter takes place a plurality of times.

8. A method as claimed in claim 1 or 2, characterized in that the first assay area is optically scanned again after an optical scanning with scanning parameters according to a first setting of the scanning parameters, with scanning parameters according to a second setting of the scanning parameters.

9. The method according to claim 1 or 2, characterized in that the test light application zones (31, 32) assigned to the respective assay zones (21; 41; 51) do not overlap during the optical scanning of the assay zones (21; 41; 51).

10. A method as claimed in claim 1 or 2, characterized in that the first quantity of light is selected to lie within a first sub-range of the working range and the second quantity of light is selected to lie within a second sub-range of the working range, which is different from the first sub-range.

11. Method according to claim 1 or 2, characterized in that a plurality of identical assay areas (41) are optically scanned at one scanning position and detected in a two-dimensional resolved manner.

12. The method of claim 1, wherein the dry chemical test element is an immunological test element.

13. An apparatus for analyzing dry chemical test elements, optically scanned using at least one of the methods of the preceding claims, comprising:

a holder (2) arranged to hold a dry chemical test element (1; 20; 30; 50) for optical scanning analysis,

a detector means (4) arranged to detect a measuring beam leaving an assay region (21; 41; 51) carrying one or more immobilised optically active substances and having a corresponding measured light intensity, and

a control device (5) arranged to control the optical scanning of the dry chemical test element (1; 20; 30; 50) as follows:

during optical scanning of the first assay region, a measuring light beam having a first measuring light intensity leaves the first assay region, scanning parameters are selected in accordance with a first setting of the scanning parameters, the operating range of the detector device (4) and a first light quantity of the measuring light beam impinging on the detector device (4) are adjusted relative to one another, and

during optical scanning of the second assay region, a measuring light beam having a second measuring light intensity differing from the first measuring light intensity leaves the second assay region, the scanning parameter is selected on the basis of a second setting of the scanning parameter differing from the first setting of the scanning parameter, and the operating range of the detector device (4) and a second light quantity of the measuring light beam impinging on the detector device (4) are adjusted relative to each other.

14. A device as claimed in claim 13, characterized in that the control device (5) is arranged to set one or more variables selected from the following variable groups as scanning parameters; scanning speed, exposure time, test light intensity of the test light beam, amplification factor of the detector device (4) and power supply of the assay area (21; 41; 51).

15. An apparatus as claimed in claim 13 or 14, characterized in that the control means (5) are arranged to keep at least one of the first and second settings of the scanning parameter constant.

16. Device according to claim 13 or 14, characterized in that the control device (5) is arranged to change the scanning parameters according to the first setting of the scanning parameters to the scanning parameters according to the second setting of the scanning parameters during the continuous scanning of the dry chemical test element (1; 20; 30; 50).

17. An apparatus as claimed in claim 13 or 14, characterized in that the control means (5) are arranged to cause a change of the scan parameter according to a first setting of the scan parameter to a second setting of the scan parameter as a function of the measurement information derived from a pre-scanning process carried out beforehand.

18. An apparatus according to claim 13 or 14, characterized in that the control device (5) is arranged to cause a change of the scan parameter according to the first setting of the scan parameter to the scan parameter according to the second setting of the scan parameter as a function of current measurement information derived from a current measurement value of the optical scanning process of the dry chemical test element (1; 20; 30; 50).

19. Device according to claim 13 or 14, characterized in that the control device (5) is arranged to change a plurality of times during the optical scanning of the dry chemical test element (1; 20; 30; 50) between a scanning parameter according to a first setting of the scanning parameter and a scanning parameter according to a second setting of the scanning parameter.

20. A device as claimed in claim 13 or 14, characterized in that the control device (5) is arranged to optically scan the first assay area again with a scanning parameter according to a second setting of the scanning parameter after the optical scanning with the scanning parameter according to the first setting of the scanning parameter.

21. A device as claimed in claim 13 or 14, characterized in that the control means (5) are arranged to form test light application zones (31, 32), which test light application zones (31, 32) are assigned to respective assay zones such that they do not overlap during optical scanning of the assay zones.

22. A device as claimed in claim 13 or 14, characterized in that the control means (5) are arranged to select the first quantity of light to lie in a first sub-range of the operating range and the second quantity of light to lie in a second sub-range of the operating range, which sub-range is different from the first sub-range.

23. A device as claimed in claim 13 or 14, characterized in that the control means (5) and the detector means (4) are arranged to optically scan a plurality of identical assay areas (41) in one scanning position and to detect them in a two-dimensional resolved manner.

24. Device according to claim 13 or 14, characterized in that a test light beam is generated using the light source (3) and applied to the assay area (21; 41; 51) of the dry chemical test element (1; 20; 30; 50) in the holder (2).

25. Device according to claim 13 or 14, characterized in that the electrode means are couplable to the assay region (21; 41; 51) and are adapted to supply electrical energy to the assay region (21; 41; 51) of the dry chemical test element (1; 20; 30; 50).

26. The device of claim 13, wherein the dry chemical test element is an immunological test element.

27. Use of the method of at least one of claims 1 to 12 or the device of at least one of claims 13 to 26 for conducting an immunoassay.