RU2791099C2 - Method for determining analyte in a sample - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: essence of the invention lies in the fact that at least one sample is applied to the test field; obtaining a set of images of at least one area of the test strip, and the area of the test strip contains at least part of the test field, which is applied to the sample; comparing the images obtained with the light source turned on and off, and determining the difference in light intensities, on the basis of which the concentration of the analyte in the sample is determined.

EFFECT: ensuring the possibility of reliable and accurate determination of the analyte in the sample.

11 cl, 9 dwg

Description

FIELD OF TECHNOLOGY

The present application relates to a detection method for determining an analyte in a sample. The present invention also relates to a computer program with software for performing the method in accordance with the present invention. Furthermore, the present invention relates to a mobile device and a kit. The method, computer program, and mobile device and kit of the present invention may be used in medical diagnostics to qualitatively and/or quantify one or more analytes in one or more body fluids. However, other applications of the present invention are possible.

BACKGROUND OF THE INVENTION

In the field of medical diagnostics, it is often necessary to determine one or more analytes in bodily fluid samples such as blood, interstitial fluid, urine, saliva, or other types of bodily fluids. Examples of analytes to be determined are glucose, triglycerides, lactate, cholesterol, or other types of analytes commonly found in these body fluids. Depending on the concentration and/or presence of the analyte, an appropriate treatment can be selected if necessary.

Typically, devices and methods known to those skilled in the art use test elements containing one or more test chemicals that, in the presence of the analyte to be determined, are capable of performing one or more detectable detection reactions, such as detection reactions determined by optically. For these test chemicals, reference may be made to, for example, J. Hoenes et al.: The Technology Behind Glucose Meters: Test Strips, Diabetes Technology & Therapeutics, Volume 10, Supplement 1, 2008, S-10 to S-26 . There are other types of test chemical that can be used to implement the present invention.

In the case of analytical measurements, especially analytical measurements based on color reactions, one of the technical problems is to evaluate the color change that occurs as a result of the detection reaction. In addition to the use of specialized analytical devices such as portable glucometers, the use of publicly available electronic devices such as smartphones and laptop computers has become increasingly popular in recent years. WO 2012/131386 A1 describes a test device for performing an assay, the test device comprising: a container containing a reagent, the reagent reacting with the applied test sample to exhibit a color or pattern change; a portable device, such as a mobile phone or a laptop computer, comprising a processor and an imaging device, wherein the processor is configured to process data received by the imaging device and output a test result for the applied test sample.

WO 2015/078954 A1 describes a method, an analytical device and an analytical system for determining the concentration of at least one analyte in a physiological fluid. The method includes: a) applying a sample of physiological fluid to the test carrier; b) illuminating the test carrier with at least one light source; c) receiving light emitted by the test carrier using at least one detector; d) determining the analyte concentration by evaluating at least one detector signal generated by the detector. At least one light source is modulated using at least two modulation frequencies. The detector signal is demodulated with at least two modulation frequencies to generate at least two demodulated detector signals, each demodulated detector signal corresponding to one of the modulation frequencies. The method includes determining a fault based on a comparison of at least two demodulated detector signals.

US 2017/0343480 A1 describes providing a method for measuring blood glucose levels with a handheld terminal using a strip module. The strip module contains an ink pad that changes color depending on the pattern applied to the ink pad. The strip module also contains a transparent strip having a first side and a second side. The first side is opposite the second side. An ink pad is mounted on the first side of the transparent strip, and the transparent strip reflects light emanating from a light source of a portable terminal adjacent to the second side and transmits light to the ink pad.

US 2015/233898 A1 describes a test strip module comprising a sheath, a sheathed test strip, and a positioner extending down past the mating surface to the face of the mobile computing device. The position lock has a shape corresponding to the element on the front surface of the mobile computing device.

US 6,267,722 B1 describes systems and methods for medical diagnosis or patient risk assessment. These systems and methods are intended for use in the point of care, such as emergency rooms and operating rooms, or in any situation where fast and accurate results are required. The systems and methods process patient data, such as point-of-care diagnostic tests or tests, including immunochemical assays, electrocardiograms, x-rays, and other similar tests, and provide an indication of a medical condition or risk, or lack thereof. These systems include a device for reading or evaluating test data and software for converting these data into diagnostic or risk assessment information.

The reliability and accuracy of analytical measurements using mobile computing devices usually depend on a large number of technical factors. In particular, a huge number of mobile devices with cameras are available on the market, all of which have different technical and optical properties that must be taken into account in analytical measurements. For example, the measurement of physical and biochemical parameters using mobile devices is disclosed in EP 3 108 244 A1 and WO 2015/120819 A1, describing a test strip module containing a sheath, a sheathed test strip, and a position lock extending down past the mating surface to the front surface of a mobile computing device. The position lock has a shape corresponding to the element on the front surface of the mobile computing device.

In addition, the reliability and accuracy of analytical measurements using mobile computing devices are usually highly dependent on the illumination and light conditions during the measurement. For example, in US 6,574,425 B1, a modulated light source emits light to illuminate a target surface that has a specific color and color cast. The light reflected from the target surface is detected by an optical detector. The output of the optical detector is processed and fed back to the optical detector to compensate for any shift caused by ambient light, temperature, or other external factors, and differentially amplified to generate an output indicative of the color and tone of the target surface. The output of the differential amplifier is then demodulated by a synchronous detector to produce a substantially constant DC voltage that indicates a color or shade of color on the target surface. If the color tone of the target surface is indicative of a certain measurable quantity or quality (for example, an analyte concentration), the DC voltage is converted using a lookup table or mathematical formula into the corresponding quantitative or qualitative measurement. This conversion compensates for any changes in the intensity of the modulated light source due to changes in temperature.

US Pat. No. 4,553,848 A describes a method and apparatus for determining and evaluating the optical properties of a sample using a light source that has alternating light and dark phases, a detector that captures light from the light source through the sample under test, and a circuit that combines and digitizes the signals, received from the detector, which contains an integrator and can be connected to the detector. The signals emitted by the detector are integrated both during at least part of the light phase and at least during part of the dark phase. The integral obtained during the dark phase is subtracted from the integral obtained during the light phase to determine the results. The integrator that is used to integrate the signals is used as a double-integration type analog-to-digital converter to convert the integral into a digital signal. To achieve maximum accuracy and simplicity in the integration and digitization step, each part of the light or dark phase is followed by a voltage measurement period during which the signals coming from the detector are applied sequentially and with opposite mathematical signs to one integrator. The integration is performed over an integer number of voltage measurement periods to obtain an overall integral.

EP 1 912 058 A1 describes an apparatus and method for detecting and evaluating optical signals. The device comprises a mixer producing a light control signal from two different control signals (AN1, AN2) and a light source controlled by the light control signal. The signal source outputs one of the control signals with frequency and intensity. The measurement signal and the control signal are fed to a frequency selective amplifier. The output signals (A1, A2) are applied to an evaluation unit which compares the output signals. Stray light determines measurement noise information from the comparison result. Also included is an independent claim for a method for detecting and analyzing an optical signal for detecting an analyte in an analyte.

Despite the advantages of using a mobile computing device for analytical measurements, a number of technical problems remain. In particular, it is necessary to improve and ensure the reliability and accuracy of measurements. The main difficulty lies in the presence and influence of ambient light. The reliability and accuracy of the analytical measurement can be significantly affected by the lighting conditions at the time of imaging the test strip for the analytical measurement when using a mobile phone camera. In particular, ambient light can have a significant effect on lighting conditions, for example, due to the presence of different lighting means in different specific locations and/or depending on where the image is taken and when the image is taken during day or night. In particular, ambient light can interfere with the evaluation of the color formed on the reagent field of the test strip.

Problem to be solved

Therefore, it is desirable to provide methods and apparatuses that solve the aforementioned technical problems of analytical measurements using mobile devices such as mobile consumer electronics devices, in particular multi-purpose mobile devices that are not designed for analytical measurements, such as smartphones or tablet computers. In particular, methods and devices should be proposed to ensure the reliability and accuracy of measurements.

SUMMARY OF THE INVENTION

This problem is solved by using a detection method for determining at least one analyte in at least one sample, a computer program, a mobile device, and a set with features of independent claims. Advantageous embodiments of the invention, which can be implemented separately or in any arbitrary combination, are given in the dependent claims.

As used herein, the terms "have", "comprise" or "include" or any arbitrary grammatical variations thereof are used in a non-exclusive manner. Thus, these terms can refer both to a situation in which, in addition to the feature represented by these terms, there are no other features in the object described in this context, and to a situation in which one or more additional features are present. For example, the expressions "A has B", "A contains B" and "A includes B" can refer to a situation in which, in addition to B, there is no other element in A (i.e., a situation in which A consists only and exclusively from B), and to a situation in which, in addition to B, object A contains one or more additional elements, such as element C, elements C and D, or even other elements.

In addition, it should be noted that the terms "at least one", "one or more", or similar expressions indicating that a feature or element may be present once or more than once, will generally be used only once when presenting the corresponding feature or element. In the following, in most cases, when it comes to the corresponding feature or element, the expressions "at least one" or "one or more" will not be repeated, despite the fact that the corresponding feature or element may be present once or more than once. times.

In addition, hereinafter, the terms "preferably", "more preferably", "especially", "in particular", "more specifically" or similar terms are used together with optional features, without limiting alternative possibilities. Thus, the features represented by these terms are optional features and are in no way intended to limit the scope of the claims. The present invention, as will be understood by a person skilled in the art, can be implemented using alternative features. Likewise, features represented by "in an embodiment of the present invention" or similar expressions are intended to be used as optional features, without any limitation as to alternative embodiments of the present invention, without any limitation as to the scope of the present invention, and without no restrictions as to the possibility of combining the features thus presented with other optional or mandatory features of the present invention.

In a first aspect, a determination method for determining at least one analyte in at least one sample is described. The method includes the following steps, which, for example, can be performed in this order. However, it should be noted that another order is also possible. In addition, it is possible to perform one or more steps of the method one or more times. In addition, it is also possible to perform two or more method steps simultaneously or in an overlapping manner in time. The method may further include steps that are not listed.

The determination method includes the following steps:

a) providing at least one mobile device containing at least one camera and at least one light source;

b) providing at least one test strip containing at least one test field, and the test field contains at least one test chemical for performing an optical detection reaction in the presence of an analyte;

c) applying at least one sample to the test field;

d) obtaining a set of images of at least one area of the test strip, and the specified area contains at least part of the test field on which the sample is applied, including

d1) obtaining at least one image before applying the sample to the test field with the light source turned off;

d2) obtaining at least one image before applying the sample to the test field with the light source turned on; And

d3) obtaining at least one image after applying the sample to the test field;

e) determination of the analyte concentration in the sample using the images obtained in step d).

As used herein, the term "determination of an analyte in a sample" is a broad term, and its usual and generally accepted meaning should be left to a person skilled in the art and should not be limited to a special or individual meaning. This term, in particular, may refer, without limitation, to the quantitative and/or qualitative determination of at least one analyte in an arbitrary sample. For example, the sample may contain a bodily fluid such as blood, interstitial fluid, urine, saliva, or other types of bodily fluids. The result of an analytical measurement, for example, may be the concentration of the analyte and/or the presence or absence of the analyte to be determined. Specifically, as an example, the analytical measurement may be a blood glucose measurement, thus the result of the analytical measurement may be, for example, a blood glucose concentration.

For example, in step a), a mobile device may be provided, comprising at least one camera and at least one light source. As used herein, the term "mobile device" is a broad term and its common and conventional meaning should be left to those skilled in the art and should not be limited to a specific or individual meaning. This term, in particular, may refer, without limitation, to a mobile electronics device, more specifically to a mobile communication device such as a cellular phone, smartphone. Additionally or alternatively, as will be described in more detail below, a mobile device may also refer to a tablet computer, laptop, or any other type of portable computer containing at least one camera and at least one light source.

As used herein, the term "camera" is a broad term and its common and conventional meaning should be left to those skilled in the art and should not be limited to a specific or individual meaning. This term, in particular, may refer, without limitation, to a device containing at least one imaging element, configured to record or obtain spatially resolved one-dimensional, two-dimensional, or even three-dimensional optical information. By way of example, the camera may comprise at least one camera chip, such as at least one charge-coupled device (CCD) chip and/or at least one complementary metal oxide semiconductor (CMOS) chip configured to image recording. For example, the camera may be a color camera having at least three color pixels. The camera may be a CMOS color camera. For example, a camera may contain black and white pixels and color pixels. Color pixels and black and white pixels can be combined inside the camera. The camera may include at least one color camera and at least one black and white camera, such as a CMOS black and white camera. The camera may include at least one CMOS chip for black and white photography. A camera typically may comprise a one-dimensional or two-dimensional group of image sensors, such as pixels. For example, a camera may contain at least 10 pixels in at least one dimension, such as at least 10 pixels in each dimension. However, it should be noted that other chambers are practically possible. The camera may be a camera of a mobile communication device. In particular, the invention should be applicable to cameras that are commonly used in mobile communication devices such as laptop computers, tablets or, in particular, cellular phones such as smartphones. Thus, in particular, the camera may be part of a mobile device, which, in addition to at least one camera, contains one or more data processing devices, such as one or more data processors. However, it is practically possible to use other cameras. Said camera, in addition to at least one camera chip or imaging chip, may contain additional elements such as one or more optical elements, such as one or more lenses. As an example, the camera may be a fixed focal length camera including at least one lens that is stably adjusted with respect to the camera. However, in the alternative, the camera may also include one or more adjustable lenses that can be adjusted automatically or manually.

In particular, the camera may be a color camera. Thus, for example, for each pixel, color information, such as color values for the three colors of the red, green, blue (R, G, B) palette, can be provided and generated. More color values are also practical, such as four colors for each pixel. Color cameras are generally known to those skilled in the art. Thus, as an example, each pixel of a camera chip can have three or more different color sensors, such as color shooting pixels, such as one pixel for red (R), one pixel for green (G), and one pixel for blue (B). . For each of the pixels, eg R, G, B, the pixels may record values, eg numerical values ranging from 0 to 255, depending on the intensity of the corresponding color. Instead of using three-color variants such as R, G, B, as an example, four-color variants such as C, M, Y, K or the like may be used.

As used herein, the term "mobile device light source" refers to an arbitrary light source of a mobile device. The term "light source" refers to at least one device configured to generate light to illuminate an object. As used herein, the term "light" generally refers to electromagnetic radiation in one or more of the visible spectral range, the ultraviolet spectral range, and the infrared spectral range. The term "visible spectral range" generally refers to the spectral range from 380 nm to 780 nm. Preferably, the light used in the present invention is light in the visible spectral range. The light source may include at least one light emitting diode embedded in the mobile device. In particular, the light source may be the backlight of a mobile device, in particular a mobile phone. The mobile device may include additional lighting devices, such as at least one light source illuminating the display, and/or the display may be designed as an additional light source.

The light source may have two states: an on state in which it generates a light beam to illuminate the test strip, and an off state in which the light source is turned off. As used herein, the term "on" refers to the fact that the light source is activated and/or turned on to illuminate the test strip. The term "off" refers to the fact that the light source is in the off state or actively turned off. As stated above, in step d1) at least one image is obtained with the mobile device's light source turned off. This can provide an image containing only the light intensities of the ambient light sources and independent of the illumination provided by the mobile device's illumination source. In step d2), the illumination source is turned on so that a second image can be obtained containing illumination intensities from both ambient light and illumination from the mobile device's illumination source.

The illumination source may comprise at least one light emitting diode (LED) embedded in the mobile device. The illumination source may comprise at least one white light LED. The white light LED can be driven with a short current pulse so that the white light LED can be configured to generate a bright flash of light. The light source may be configured to continuously illuminate the test strip during image acquisition. Unlike electronic flashes, the white light LED flash duration can be several hundred (100) ms, which may allow the light source to continuously illuminate the test strip during LED flash image acquisition. Alternatively, the LED may be configured to continuously illuminate the test strip in a non-flashing mode. In step b) at least one test strip containing at least one test field can be provided. As used herein, the term "test strip" is a broad term, and its usual and generally accepted meaning should be left to the person skilled in the art and should not be limited to a special or individual meaning. The specified term, in particular, may refer, without limitation, to an arbitrary element or device, made with the possibility of carrying out a reaction to determine the color change. The test strip may in particular comprise a test field containing at least one test chemical for carrying out an optical determination reaction in the presence of an analyte to determine at least one analyte. The test strip, for example, may contain at least one substrate, such as at least one carrier, coated on it or integrated into it at least one test field. As an example, at least one carrier may be in the form of a strip, thereby converting the test element into a test strip. These test strips are commonly used and widely available. One test strip may contain one test field or a combination of test fields containing identical or different test chemicals. At least one sample may be applied to the test strip. In particular, the test strip may be a high dosage test strip, such as a test strip configured to have at least one sample applied to it on the second side and further configured to carry out a reaction to detect a color change such that that the color change can be identified on the first side of the test strip, and in particular the first side is opposite the second side of the test strip.

As used herein, the term "test field" is a broad term, and its common and conventional meaning should be left to those skilled in the art and should not be limited to a special or individual meaning. The term particularly may refer to, without limitation, a coherent amount of a test chemical, such as a field, such as a round, polygonal or rectangular field, containing one or more layers of material, with at least one layer of test field containing a test Chemical substance. Other layers may be present to provide certain optical properties, such as reflective properties, to provide distribution properties for spreading the sample, or to provide separation properties, for example to separate particulate components in the sample, such as cellular components.

As used herein, the term "test chemical" is a broad term, and its usual and generally accepted meaning should be left to the person skilled in the art and should not be limited to a special or individual meaning. This term, in particular, may refer, without limitation, to a chemical compound or collection of chemical compounds, for example a mixture of chemical compounds, suitable for conducting a detection reaction in the presence of an analyte, while the detection reaction can be determined by a specific method, for example optically. The determination reaction, in particular, may be specific to the analyte. The test chemical in this case, in particular, can be an optical test chemical, such as a color change test chemical that changes color in the presence of an analyte. The color change, in particular, may depend on the amount of analyte present in the sample. The test chemical, for example, may contain at least one enzyme, such as glucose oxidase and/or glucose dehydrogenase. In addition, other components may be present, such as one or more dyes, mediators, and the like. Test chemicals are generally known to those skilled in the art, and reference may be made to J. Hoenes et al.: Diabetes Technology and Therapeutics, Vol. 10, Supplement 1, 2008, pp. 10-26. However, other test chemicals are practical.

As used herein, the term "analyte" is a broad term, and its usual and generally accepted meaning should be left to a person skilled in the art and should not be limited to a special or individual meaning. The term, in particular, may refer, without limitation, to one or more specific chemical compounds and/or other parameters to be determined and/or measured. By way of example, at least one analyte may be a chemical compound that takes part in metabolism, such as one or more of glucose, cholesterol, or triglycerides. Additionally or alternatively, other types of analytes or parameters may be determined, such as pH.

As used herein without limitation, the term "image" may particularly refer to data recorded by a camera, such as a collection of electronic readings from an imaging device such as pixels on a camera chip. Thus, the image itself may contain pixels, the pixels of the image being correlated with the pixels of the camera chip. Therefore, "pixels" refer to either units of image information generated by individual pixels of the camera chip, or directly to individual pixels of the camera chip. The image may contain raw pixel data. For example, an image may contain data in the RGGB range, one color data for one of the R, G, or B pixels, a Bayer pattern image, and the like. The image may contain estimated pixel data such as a full color image or an RGB image. The raw pixel data may be evaluated, for example, using demosaicing algorithms and/or filtering algorithms. These methods are generally known to the person skilled in the art.

The term "obtaining at least one image" refers to one or more of the following: image formation, image recording, image acquisition, image acquisition. The term "obtaining at least one image" may include obtaining a single image and/or a collection of images, such as a sequence of images. Acquisition of at least one image may be initiated by a user action or may be initiated automatically, for example, as soon as the presence of at least one object in the field of view and/or within a given sector of the camera's field of view is automatically determined. These methods of automatic image acquisition are known, for example, in the field of automatic barcode readers, such as, for example, from applications for automatic barcode reading.

For example, in step d) a collection of images of at least one area of the test strip may be obtained. At least one area of the test strip may contain at least part of the test field, which can be applied to the sample. In particular, as mentioned above, the images obtained in step d) can, for example, be used to determine the concentration of the analyte in the sample in step e).

In addition, the determination method may further include step e) comparing the respective images obtained in step d) with the light source on and off, and determining the light intensity difference. In particular, the term "corresponding images" may refer to, without limitation, at least two images of an object, such as a test strip, wherein one of the at least two images is obtained with the light source turned on and the other from at least at least two images are obtained with the light source turned off, preferably with other conditions of the situation unchanged. As an example, at least one image obtained in step d1) can be compared with at least one image obtained in step d2). Additionally or alternatively, at least one image obtained in step d3) can, for example, be compared with one of the images obtained in step d1) and/or step d2). In particular, step e) may include determining information on light intensity differences between respective images obtained in step d).

In addition, step e) may, for example, include using the result of step e) to determine the concentration of the analyte in the sample. In particular, the light intensity differences determined in step e) can be used to determine the concentration of the analyte in the sample. Thus, information about differences in light intensity can, for example, be taken into account when determining the concentration of an analyte in a sample.

In addition, step e) may, for example, include

e1) obtaining at least one element of information about the color of the part of the test field on which the sample is applied for each image to be compared;

e2) converting said color information item to at least one light intensity information item using at least one camera-specific conversion function; And

e3) determining the light intensity difference using the light intensity information elements of the respective images with the light source turned on and off.

As used herein, the term "color information element" is a broad term, and its common and conventional meaning should be left to those skilled in the art and should not be limited to a specific or individual meaning. The term may in particular refer to, without limitation, an indication or information regarding the color of an arbitrary object, such as, for example, in this case, the color of at least a portion of a test field onto which a sample may be applied. As an example, the color information element may indicate the color of a portion of the test field using coordinates to describe the color in an arbitrary color coordinate system. Thus, at least one element of color information, in particular, may mean at least one element of photometric information indicating light intensity, weighted with one or more spectral sensitivity functions, such as one or more spectral sensitivity functions determined by spectral sensitivity. camera or component thereof, such as a camera chip and/or one or more spectral filters, such as R, G, B filters. A person skilled in the art is generally aware of several color coordinate systems that can also be used in the context of the present invention. In particular, the color information element may contain information about one, more than one, or even all color coordinates of several or even all pixels of at least one image showing at least a portion of the test area on which the sample can be applied. The color information element, as an example, may be digital information. In particular, the color information element may be or may contain, for example, at least one numeric value in the range of 0 to 255 for one or more color coordinates, for example, for one or more of R, G, and B.

By way of example, the color information element may particularly contain intensity information, in particular if only one color coordinate is evaluated. Thus, by way of example, in particular if a single color coordinate is considered and/or evaluated, the color information may be or may comprise a color channel or color coordinate value, whereby, by way of example, a high value may also correspond to a high intensity, and a low value can correspond to a low intensity. As a rule, a change in color can also be accompanied by a change in intensity. In particular, in this case, the steps e1) and e2) listed above need not be separate method steps. Thus steps e1) and e2) can at least partially be combined.

In a simple case, by way of example, a color information element may be or may contain a value for a color coordinate known to undergo the most significant or strongest change during a color change or color formation reaction of a test chemical. For example, if a particular test chemical is known to change its hue most strongly in the blue spectral range during the color change reaction used to determine the analyte, a blue color coordinate may be used and the color information element may be or may be contain blue color coordinate values determined for all pixels or for at least a group of pixels of at least a portion of the test field in the image on which the sample can be applied.

As indicated above, the color information element may be converted to at least one light intensity information element in substep e2) using at least one camera-specific conversion function. As used herein, the term "light intensity information element" is a broad term, and its common and conventional meaning should be left to those skilled in the art and should not be limited to a special or individual meaning. This term, in particular, may refer, without limitation, to the display of information regarding the intensity of light, in particular the intensity of illumination or exposure level, of an arbitrary object, such as, for example, in this case, at least part of the test field, which can be sample applied. As an example, the light intensity information element may indicate the light intensity of a part of the test field in terms of an exposure value (EV; exposure value), such as an exposure level. The at least one light intensity information item may specifically mean at least one information item indicative of the radiometric illumination power per unit area, for example in W/m or similar units. In particular, the light intensity information item may be obtained using at least one camera-specific transform function.

As used herein, the term "camera-specific transform function" is a broad term, and its common and conventional meaning should be left to those skilled in the art and should not be limited to a special or individual meaning. This term, in particular, may refer, without limitation, to a mathematical operation to describe an arbitrary action or mode of operation of the camera when converting illumination or light intensity from at least one object, in particular, at least part of the test field, which can be a pattern is applied to the color information, for example, to at least one element of the color information. The camera-specific conversion function may in particular be dependent on camera specifications such as an imaging chip or one or more sensors, a data processing device such as a processor, optical elements such as one or more lenses, or any other specifications. cameras.

The camera-specific transform function, for example, may be determined in an empirical or semi-empirical manner and, as an example, may be predetermined or may be determined by one or more calibration processes, which may also be part of the method. Thus, for example, a camera-specific transform function may be wholly or partially defined using one or more reference fields with known color coordinates or known color properties. To determine a camera-specific transform function, one or more reference fields, by way of example, can be illuminated under one or more known lighting conditions, such as known intensity or intensities, and color information, such as at least one color information item. , can be measured with a camera. Thus, a relationship between at least one element of color information and intensity can be determined. A camera-specific transform function, for example, may be defined or stored using one or more of a curve, graph, analytical transform function, table, matrix, or any other means indicating an intensity value for a particular color information item, or vice versa. The camera-specific conversion function, as an example, may be stored in a storage device such as a volatile or non-volatile storage device. A camera-specific conversion function, as an example, may be predefined for a particular camera type. Thus, by way of example, a set of camera-specific transform functions may be predetermined, e.g., for a set of specific mobile devices, and the method may involve selecting an appropriate camera-specific transform function from a set of camera-specific transform functions according to a specified type of mobile device. .

Furthermore, in step e), the light intensity differences can be converted into color information element differences for the respective images. In particular, the light intensity differences can be converted to color information element differences for the respective images using the inverted function of the camera-specific conversion function.

In particular, the camera-specific transform function may be a non-linear function. A camera-specific conversion function dependent on the camera may, for example, be capable of converting light intensity, eg measured in exposure value (EV), into color information, eg, an RGB value. Thus, the camera-specific transform function may, for example, be a non-linear light intensity transform function. Additionally or alternatively, a camera-specific conversion function may, for example, be capable of converting light intensity or exposure level, such as measured in exposure value (EV), into color information, such as JPEG brightness. Thus, the camera-specific conversion function may, for example, be a non-linear exposure level sensitivity function. In particular, the camera-specific transform function may be, for example, one or more of a non-linear light intensity transform function and a non-linear exposure level sensitivity function.

In addition, substep or step d3) may include at least two additional substeps. In particular, d3) may include

d3i) obtaining at least one image with the light source turned off; And

d3ii) obtaining at least one image with the light source turned on.

In particular, step e) may further include using the light intensity difference between the images obtained in steps d3i) and d3ii). Thus, step e) of the determination method may further include using the light intensity difference between the images obtained in steps d3i) and d3ii) to determine the concentration of the analyte in the sample.

In addition, one or more of steps d1) to d3) may be repeated. In particular, repeating one or more of steps d1), d2) and/or d3) can, for example, control the kinetic curve of the measurement of the optical detection reaction. Thus, the detection method may further include monitoring a kinetic curve for measuring the reaction of the optical detection.

In step c) of the determination method, the sample can in particular be applied to the test field from the side opposite the chamber. The test strip, in particular the upper dosage test strip, may be positioned relative to the chamber such that one side of the test field may face the chamber and the other side of the test field may be turned away from or away from the camera. In particular, the sample may be applied to the side of the test field opposite or away from the chamber.

In particular, a holder can be used to position the test strip relative to the mobile device. In particular, the test strip can be positioned such that the test field is at a distance from the camera, in particular from the camera of the mobile device. For example, the mobile device may be positioned so that the camera faces a first direction, such as an upward direction, in particular facing the first side of the test field, and the sample can be applied to the second side of the test field opposite the first side. Thus, the determination method may include using a holder to position the test strip relative to the mobile device, wherein the test strip may be positioned so that the test field is at a distance from the camera, while the camera may be located on the first side of the test field. and while the sample can be applied on the second side opposite the first side.

In particular, the holder can be opened from the second side in such a way that the test area can be uncovered from the second side. In particular, the holder cannot cover the test field on the second side in such a way that the holder does not interfere or stand in the way of applying the sample to the second side of the test field. In addition, the holder may have an opening so that the test field may also be uncovered on the first side.

In addition, the test field may be, for example, at least partially translucent. In particular, in step e) of the determination method, the effect of ambient light falling through the test field on the camera can be determined. As used herein, the term "translucent" is a broad term and its normal and conventional meaning should be left to those skilled in the art and should not be limited to a specific or individual meaning. This term, in particular, may refer, without limitation, to a characteristic or property of an arbitrary object that allows light, in particular incident light, to pass through the object. While a translucent object may typically transmit light, thus allowing more than 0% of the light to pass through, a translucent object may additionally not completely transmit incident or ambient light, thus allowing less than 100% of the light to pass through. For example, a translucent test field may allow a limited amount of light to pass through the test field. In particular, incident or ambient light, such as incoming light incident on the test field, may at least partially pass through the test field. In particular, the test field can, for example, transmit up to 60% of the incident light. Preferably, the test field can transmit up to 40% of the incident light. More preferably, the test field can transmit up to 30% of the incident light. In particular, the test field may, for example, transmit 1% to 60% of the incident light, preferably 1% to 40% of the incident light, more preferably 1% to 30% of the incident light. However, said transmission may depend on the spectral properties of the incident light. In addition, the transmission may in particular depend on the state or properties of the test field, for example on the dry or wet state of the test field. Thus, the transmission may in particular depend on the wetting state, the moisture state or the dampness state of the test field, in particular on the wetting of the test field with the sample. For example, a test field in a dry state may particularly exhibit a higher incident light transmittance than, for example, the same test field in a wet or wet state, such as a test field on which a sample has been applied. The above transmission values, by way of example, can be provided for at least one wavelength within the visible spectral range.

The test strip may, for example, further comprise a reference field. In particular, at least part of the reference field may, for example, consist of an area of the test strip, in particular of the area of the test strip containing at least part of the test field. Thus, the reference field and the test field can be located at a close distance, for example, next to each other.

In addition, the reference field may be opaque. In particular, the term "opaque" can, without limitation, refer to a characteristic or property of an arbitrary object that does not allow light to pass through the object. In particular, the opaque reference field may be configured to prevent incident or ambient light from passing through the reference field. As an example, the reference field may transmit less than 3%, preferably less than 2%, more preferably less than 1% of ambient light through the reference field. In particular, the reference field may be, for example, 100% opaque, thus the reference field, as an example, may transmit 0% of incident or ambient light through the reference field.

Step d) of the determination method may further include substep d4) of obtaining at least one image of the reference field. In addition, the image of the reference field can, for example, be taken into account in step e).

The reference field, for example, may contain at least one white field. In particular, the white field, more specifically the white field contained by the reference field, may, for example, be used to calibrate the camera, for example, to set the white balance of the camera.

The determination method may further include at least one step of checking camera-specific properties. For example, a camera-specific transform function can be defined in a camera-specific property check step. Other camera-specific properties, such as color authenticity, can also be checked in this step.

In a further aspect, a computer program is described comprising software tools for fully or partially performing the determination method. Thus, in particular, step d), step e) and optionally step e) of the determination method can be performed by a computer program. In particular, the computer program comprises software, such as computer-executable instructions for fully or partially implementing a method for determining when the computer program is running on a computer or on a computer network, such as a processor of a mobile device. In particular, the computer may be wholly or partly integrated into the mobile device, and the computer program may in particular be implemented as a software application. In particular, the computer program may be stored on a computer-readable storage medium, such as a storage device or data storage device of a mobile device. However, in the alternative, at least a portion of the computer may be located outside the mobile device.

In addition, this document describes and proposes a data carrier containing a data structure stored thereon, which, after being loaded into a computer or computer network, for example, into a random access memory or main storage device of a computer or computer network, can perform a determination method according to one or more embodiments of the invention described herein, such as steps d) and e) and optionally e), including possible substeps.

In addition, this document describes and proposes a computer program product with program code means stored on a computer-readable medium for performing a method according to one or more embodiments of the invention described herein while executing a program on a computer or computer network, for example, the steps d) and e) and optionally e), including possible substeps. As used herein, the term "computer program product" refers to the program as a marketable product. This product, as a rule, can exist in an arbitrary format, for example, in paper format or on a computer-readable data carrier. In particular, the computer program product may be distributed over a data network.

Finally, this document describes and proposes a modulated data signal that contains instructions, readable by a computer system or computer network, for implementing a method for determining according to one or more embodiments of the invention described herein, in particular, one or more steps of the method for determining , as mentioned above or as further described below, for example steps d) and e) and optionally e), including possible sub-steps.

In particular, this document further describes:

- a computer or computer network comprising at least one processor, wherein the processor is configured to carry out the determination method according to one of the implementation options set forth in this description, for example steps d) and e) and optionally e), including possible substeps,

- a data structure downloadable to a computer that is configured to carry out the method of determining according to one of the embodiments of the invention set forth in this description, when the data structure is executed on a computer, for example steps d) and e) and optionally f), including possible substeps,

- a computer program, wherein the computer program is configured to carry out the determination method according to one of the embodiments of the invention set forth in this description, when executing the program on the computer, for example steps d) and e) and optionally f), including possible substeps,

- a computer program containing software tools for implementing the method of determining according to one of the embodiments of the invention set forth in this description, when the computer program is executed on a computer or on a computer network, for example steps d) and e) and optionally f), including possible substeps,

- a computer program containing software according to the preceding embodiment of the invention, the software being stored on a computer-readable storage medium, for example steps d) and e) and optionally f), including possible sub-steps,

- a data carrier, wherein the data structure is stored on the data carrier, and the data structure is configured to carry out the determination method according to one of the embodiments of the invention set forth in this description, after being loaded into the main storage device and / or random access memory of a computer or computer network, such as steps d) and e) and optionally f), including possible substeps, and

- a computer program product containing a program code means, wherein the program code means may be stored or may be stored on a storage medium, for performing the determination method according to one of the embodiments described in this specification, if the program code means is executed on a computer or on a computer network , such as steps d) and e) and possibly f), including possible substeps.

In a further aspect of the present invention, a mobile device is described. This mobile device contains:

I) at least one chamber;

ii) at least one light source; And

iii) at least one processor.

The mobile device is configured to perform the determination method described herein, for example, according to any of the embodiments of the invention described above and/or described in more detail below, in combination with a test strip containing at least one test field, while the test field contains at least one test chemical for carrying out an optical determination reaction in the presence of an analyte.

For most of the terms used herein and possible definitions, reference may be made to the description of the method of definition given above or further described below.

By way of example, the processor may include software to carry out all or part of the determination method as described above or as further described below. In particular, the software may be configured to perform steps d), e) and optionally e) of the determination method.

In a further aspect, a kit is described for determining at least one analyte in at least one sample. The kit contains a mobile device in accordance with the present invention and at least one test strip containing at least one test field, and the test field contains at least one test chemical for performing an optical detection reaction in the presence of an analyte.

For most of the terms used herein and possible definitions, reference may be made to the description of the definition method and/or the description of the mobile device above or further described below.

In addition, the kit may contain at least one holder for positioning the test strip relative to the mobile device, while the test strip can be positioned by the holder so that the test field is at a distance from the camera, while the camera can be located on the first side of the test fields and the sample can be applied from the second side opposite the first side.

In addition, the holder can be opened on the second side in such a way that the test field can be uncovered on the second side. In particular, the holder may be configured to keep the second side of the test field uncovered so that the sample can be applied to the second side of the test field without the holder interfering.

In particular, the holder with the test strip and the mobile device may constitute an interior space. Space, for example, may be limited to a mobile device, a holder, and a test strip. In particular, the holder, the test strip, and the mobile device may be arranged such that an interior space may be formed. In addition, the camera and light source can face the interior. In particular, the holder may position the test strip in such a way that the light source can illuminate the test field.

The method and devices of the present invention can provide many advantages over prior art methods and devices for analytical measurements. The present invention can improve the reliability and usability of a method for determining an analyte in a sample compared to methods known in the art. In particular, the present invention can improve the reliability and usability of an application, such as an application containing computer-executable instructions for determining an analyte in a sample, compared to known applications or computer programs. In particular, the present invention may allow reliable determination of the analyte under varying or unstable imaging conditions. In particular, the invention can provide improved reliability and accuracy of applications or computer programs using images from the camera of a mobile device, since the influence of ambient light is taken into account in determining the result, in particular when determining the analyte in the sample.

Summarizing and not excluding additional possible implementation options, the following embodiments of the invention can be envisaged:

Option 1 implementation of the invention. A determination method for determining at least one analyte in at least one sample, comprising:

a) providing at least one mobile device containing at least one camera and at least one light source;

b) providing at least one test strip containing at least one test field, and the test field contains at least one test chemical for performing an optical detection reaction in the presence of an analyte;

c) applying at least one sample to the test field;

d) obtaining a set of images of at least one area of the test strip, and the specified area contains at least part of the test field on which the sample is applied, including

d1) obtaining at least one image before applying the sample to the test field with the light source turned off;

d2) obtaining at least one image before applying the sample to the test field with the light source turned on; And

d3) obtaining at least one image after applying the sample to the test field;

e) determination of the analyte concentration in the sample using the images obtained in step d).

Option 2 implementation of the invention. The method according to the previous embodiment of the invention, further comprising:

f) comparing the corresponding images obtained in step d) with the light source turned on and off, and determining the differences in light intensities.

Option 3 implementation of the invention. The method according to the previous embodiment of the invention, characterized in that step e) includes using the result of step e) to determine the concentration of the analyte in the sample.

Option 4 implementation of the invention. A method according to either of the two preceding embodiments of the invention, characterized in that step e) comprises:

e1) obtaining at least one element of information about the color of the part of the test field on which the sample is applied for each image to be compared;

e2) converting the color information element to at least one light intensity information element using at least one camera-specific conversion function;

e3) determining the light intensity difference using the light intensity information elements of the respective images with the light source turned on and off.

Option 5 implementation of the invention. The method according to the two preceding embodiments of the invention, characterized in that, in step e), the light intensity differences are converted into color information element differences for the respective images using an inverted function of a camera-specific conversion function.

Option 6 implementation of the invention. The method according to either of the two preceding embodiments, wherein the camera-specific conversion function is a non-linear function that converts a color information element into a light intensity information element.

Option 7 implementation of the invention. A method according to any of the three preceding embodiments, wherein the camera-specific transform function is one or more of a non-linear light intensity transform function and a non-linear exposure level sensitivity function.

Option 8 implementation of the invention. The method according to any of the preceding embodiments of the invention, characterized in that step d3 includes:

d3i) obtaining at least one image with the light source turned off; And

d3ii) obtaining at least one image with the light source turned on.

Option 9 implementation of the invention. The method according to the preceding embodiment of the invention, characterized in that step e) further comprises using the light intensity difference between the images obtained in steps d3i) and d3ii).

Option 10 implementation of the invention. A method according to any of the preceding embodiments of the invention, characterized in that one or more of steps d1) to d3) are repeated.

Option 11 implementation of the invention. The method according to the previous embodiment of the invention, characterized in that the kinetic curve of the measurement of the optical detection reaction is monitored.

Option 12 implementation of the invention. A method according to any of the preceding embodiments of the invention, characterized in that in step c) the sample is applied to the test field from the side opposite the chamber.

Option 13 implementation of the invention. The method according to the previous embodiment of the invention, characterized in that the holder is used to position the test strip relative to the mobile device, while the test strip is located so that the test field is at a distance from the camera, while the camera is located on the first side of the test field and wherein the sample is applied from the second side opposite to the first side.

Option 14 implementation of the invention. The method according to the previous embodiment of the invention, characterized in that the holder is open on the second side in such a way that the test area is uncovered on the second side.

Option 15 implementation of the invention. Method according to either of the two preceding embodiments of the invention, characterized in that the holder comprises an opening so that the test field is uncovered on the first side.

Option 16 implementation of the invention. A method according to any of the preceding embodiments of the invention, characterized in that the test field is at least partially translucent, wherein step e) determines the effect of ambient light falling through the test field on the camera.

Option 17 implementation of the invention. The method according to any of the preceding embodiments of the invention, characterized in that the test strip further comprises a reference field, wherein the area of the test strip further comprises at least a portion of the reference field.

Option 18 implementation of the invention. The method according to the previous embodiment of the invention, characterized in that the reference field is opaque.

Option 19 implementation of the invention. A method according to either of the two preceding embodiments of the invention, characterized in that step d) of the method further comprises:

d4) obtaining at least one image of the reference field.

Option 20 implementation of the invention. The method according to the previous embodiment of the invention, characterized in that the image of the reference field is taken into account in step e).

Option 21 implementation of the invention. The method according to any of the three preceding embodiments of the invention, characterized in that the reference field contains at least one white field.

Option 22 implementation of the invention. The method according to any of the preceding embodiments of the invention, characterized in that the method further includes at least one step of checking camera-specific properties.

Option 23 implementation of the invention. A computer program containing software tools for carrying out, in whole or in part, the method according to any of the preceding embodiments, in particular for carrying out steps d), e) and optionally e) of the method, when executing the computer program on a computer or on a computer network, in particular, on the processor of the mobile device.

Option 24 implementation of the invention. Mobile device containing:

I) at least one chamber;

ii) at least one light source; And

iii) at least one processor,

wherein the mobile device is configured to carry out a detection method for determining at least one analyte in at least one sample according to any of the previous embodiments of the invention in combination with a test strip containing at least one test field, and the test field contains: at least one test chemical for carrying out an optical detection reaction in the presence of an analyte.

Option 25 implementation of the invention. A mobile device according to a prior embodiment of the invention, characterized in that the processor comprises software for carrying out all or part of the method according to any of the preceding embodiments of the invention relating to the method, in particular for performing steps d), e) and optionally f) of the method .

Option 26 implementation of the invention. A kit for determining at least one analyte in at least one sample, the kit comprising a mobile device according to any of the preceding embodiments of the invention relating to a mobile device, the kit further comprising at least one test strip containing at least one a test field, wherein the test field contains at least one test chemical for carrying out an optical detection reaction in the presence of an analyte.

Option 27 implementation of the invention. A set according to a previous embodiment of the invention, wherein the set further comprises at least one holder for positioning the test strip relative to the mobile device, wherein the test strip is positioned by the holder such that the test field is at a distance from the camera, the camera being located at the first side of the test field and the sample is applied from the second side opposite the first side.

Option 28 implementation of the invention. Set according to the previous embodiment of the invention, characterized in that the holder is open on the second side so that the test area is uncovered on the second side.

Option 29 implementation of the invention. A set according to either of the two preceding embodiments of the invention, characterized in that the holder with the test strip and the mobile device constitutes an internal space, said space being limited by the mobile device, the holder and the test strip.

Option 30 implementation of the invention. A set according to a previous embodiment of the invention, characterized in that the camera and the light source face said interior space.

Option 31 implementation of the invention. A kit according to any of the preceding embodiments of the invention relating to a kit, characterized in that the holder positions the test strip in such a way that the light source is capable of illuminating the test field.

BRIEF DESCRIPTION OF GRAPHICS

Additional optional features and embodiments of the invention will be set forth in more detail in the following description of the embodiments, preferably in conjunction with dependent embodiments of the invention. In this case, the corresponding optional features can be implemented separately, as well as in any arbitrary possible combination, which will be clear to a person skilled in the art. The scope of the present invention is not limited to the preferred embodiments. Embodiments are schematically depicted in the figures. As used herein, identical reference numbers in these figures refer to identical or functionally comparable elements.

Figures include the following:

Fig. 1 is a side view of an embodiment of a kit containing a mobile device for carrying out a detection method according to the present invention;

Fig. 2 is an enlarged sectional view of an embodiment of the kit illustrated in Fig. 1;

figure 3 shows an embodiment of the image obtained by the camera of the mobile device;

on figa and 4B shows options for implementing graphs of the influence of ambient light on the color of the test field and the reference field;

5A and 5B show implementations of a camera-specific transform function graph; And

Figures 6 and 7 show embodiments of block diagrams of an embodiment of the determination method.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a side view of an embodiment of a kit 110 for detecting at least one analyte in at least one sample 114, comprising a mobile device 112 and a test strip 116. The mobile device 112, as shown in FIG. 1, comprises at least at least one camera 118, at least one light source 120, and at least one processor 122. Test strip 116 includes at least one test field 124 containing at least one test chemical 126 for performing an optical detection reaction in the presence of an analyte . In addition, three examples of light beams can be illustrated in Fig. 1 with three dotted arrows. The first dotted arrow may indicate ambient or incident light from an arbitrary ambient light source 128, such as the sun, a lamp, or any other light source, on the test area 124. The second dotted arrow may indicate light emitted by the light source 120 when the source 120 lighting included. Thus, the second dotted arrow may indicate light that is only present if the light source 120 is turned on. In case the light source 120 is turned off, the light source 120 of the mobile device 112 cannot emit light. The third dotted arrow may indicate light incident on the camera 118. In particular, if the light source 120 is turned off, the light incident on the camera 118, such as the light indicated by the third dashed arrow, may include ambient or incident light, passing through the test strip 116, such as through the test field 124, to the camera 118. Alternatively, if the light source 120 is turned on, the light incident on the camera 118, such as the light indicated by the third dotted arrow, may include in ambient or incident light passing through the test strip 116, as well as light emitted by the illumination source 120. In particular, if the light source 120 is turned on, the light incident on the camera 118 may, for example, be reflected by the test strip 116, such as, for example, the test field 124, and/or the holder 130, while the holder 130 may enter in set 110.

FIG. 2 is an enlarged sectional view of the embodiment of the kit 110 illustrated in FIG. 1. FIG. In particular, a test strip 116 is shown comprising a test field 124, where the test field 124 contains at least one test chemical 126. example, may be applied to the carrier 132. The test field 124, as illustrated in Fig.2, may, for example, contain several layers, such as, for example, a wetting layer 134 for uniform distribution of the sample 114, a filter layer 136 for filtering or separating sample components 114 for a subsequent reaction to determine the color change, which can be carried out using test chemical 126. Practically possible and other structures or formation of layers. As an example, the test chemical 126 may be positioned such that a color change can be identified on the first side 138 of the test field 124. In particular, the first side 138 may be located opposite the second side 140 of the test field 124, while the sample 114 be applied to the second side 140 of the test field 124. In particular, the camera 118 may be positioned so that it faces the first side 138 of the test field 124.

Figure 3 illustrates an embodiment of an image 142 taken by a camera 118 of a mobile device 112. Image 142, as an example, may represent at least one area 144 of a test strip 116 containing at least a portion of the test field 124, while the test field 124, for example, may be translucent. By way of example, area 144 may further comprise, in whole or in part, reference field 146, wherein reference field 146, by way of example, may be opaque and may contain at least one white field.

4A and 4B illustrate embodiments of graphs of the effect of ambient light on the color of the test field 124 and the reference field 146. In these graphs, the x-axis may indicate time t, for example, measured in seconds, and the y-axis may indicate color or reflectance R. The graph of FIG. 4A illustrates the effect of ambient light on a specific color or reflectance of the test field 124 and on a specific color of the reference field 146. In particular, the specific colors or reflectances R of the test field 124 shown in solid line and the reference field 146 shown in dotted line are shown for three different lighting conditions as a function of time. As an example, in the first lighting conditions, the ambient light source 128 may be turned off and the light source 120 of the mobile device 112 may be turned on. In particular, on the graph, the first lighting conditions can be used at time periods t ₁ , t ₃ , t ₅ and t ₇ , where t ₁ =0≤t<2 s, t ₃ =11≤t<18 s, t ₅ =32 ≤t<34 s and t ₇ =39≤t<41 s. In the second and third lighting conditions, both the illumination source 120 of the mobile device 112 and the ambient light source 128 may be turned on. However, in the third lighting condition, the ambient light may have a higher brightness level than in the second lighting condition. In particular, in the graph, the second lighting conditions may be used at time period t ₂ where t ₂ =2≤t<11 s, and the third illumination conditions may be used at time periods t ₄ and t ₆ where t ₄ =18≤t< 32 s and t ₆ =34≤t<39 s. In the graph as shown in FIG. 4A, test field 124 has a different color, such as a different color coordinate value, a different color dependent intensity, or a different intensity in a specific spectral color range, or reflectance for each of the three lighting conditions. In particular, the determined first color 148 of the test field 124 for the first lighting conditions may be less bright than the determined second color 150 of the test field 124 for the second lighting conditions and the determined third color 152 of the test field 124 for the third lighting conditions. In addition, the determined third color 152 of the test field 124 may be brighter than the determined second color 150. Thus, lighting conditions may have a direct effect on the determined color of the test field 124. However, the determined color 154 of the reference field 126 may be independent of the lighting conditions, such as this can be seen in the graph shown in FIG. 4A.

It may be noted that the given timing characteristics, such as, for example, specific times of the time periods as indicated in the description of the figures, are provided for illustrative purposes and, therefore, are intended to illustrate possible embodiments of the invention and should not be construed as limiting their scope.

The graph in FIG. 4B illustrates the effect of the combination of ambient light and on or off illumination source 120 and whether or not sample 114 is applied to test field 124 on a specific color of test field 124 and on a specific color of reference field 146. In particular, certain the colors or reflectances R of the test field 124, shown in solid line, and the reference field 146, shown in dashed line, are shown for various lighting conditions and for the sample 114, which is applied or not applied to the test field 124. In particular, in the graph, the sample 114 is not put on the test field 124 during the time 0≤t<32 s. Then, for a time of 32≤t<38 s, sample 114 is applied to test field 124, and a reaction can be performed with test chemical 126 to determine a color change. During the subsequent time period of 38≤t<86 s, the sample is applied to the test area 124 and the color change reaction may already be terminated. For example, application of the sample may occur in one second or less. The sample may permeate the test chemical 126 and a color change reaction may occur having characteristic reaction kinetics. In FIG. 4B, three different lighting conditions can again be used, with the lighting conditions used in FIG. 4B being different from the lighting conditions used in FIG. 4A.

Specifically, in the first lighting conditions used in FIG. 4B, the illumination source 120 of the mobile device 112 is turned on and the ambient light source 128 is also turned on, while in this graph, the ambient light source 128 can only include two states "on" and "off". ". The first lighting conditions used in FIG. 4B can be used at times t ₁ ', t ₄ ' and t ₇ ', where t ₁ '=0≤t<5 s, t ₄ '=16≤t<58 s and t ₇ '=75 ≤t<82 s. In the second lighting condition, the light source 120 is turned off while the ambient light source 128 is turned on. The second illumination conditions can be used in particular at times t ₂ ', t ₅ ' and t ₈ ', where t ₂ '=5≤t<13 s, t ₅ '=58≤t<68 s and t ₇ '=75≤t<82 s. In the third lighting condition, the light source 120 is on while the ambient light source 128 is off. The third lighting conditions can be used in particular at times t ₃ ' and t ₆ ', where t ₃ '=13≤t<16 s and t ₆ '=68≤t<75 s.

As can be seen in FIG. 4B, the determined first color 156, such as the first color coordinate value, the first color dependent intensity, or the intensity in the first determined spectral color range, of the reference field 146 may be substantially the same for the first illumination conditions and the third lighting conditions. Thus, for example, only the light source 120, such as on or off, can affect the specific color of the reference field 146. In particular, as illustrated in FIG. during which the light source 120 is turned off, may, for example, show a color or a reflectance R=0. However, the specific color of the test field 124, as illustrated in the graph, may show a significant dependence on the lighting conditions as well as the application of the sample 114. In particular, the specific colors of the test field 124 may differ from each other for each lighting condition. In addition, the specific color of the test field 124 may differ whether the sample 114 is applied to the test field 124 or not, even for the same lighting conditions. In particular, the determined first color 160 of test field 124 for first lighting conditions may be brighter before sample 114 is applied to test field 124 than after sample 114 is applied. As an example, the translucency of test field 124 may be reduced due to the fact that the sample 114 is applied to the test field 124, thus less light can pass through the test field 124 to the camera 118, which may result in a color transition 159. In particular, the color transition 159 may result in a less brightly defined first color 160 of the test field 124, than before, under the same first illumination conditions after sample 114 is applied to test field 124. In addition, as illustrated in FIG. from the first color 160, and in addition, the second color 162 and the third color 164 also change in brightness as a result of applying the sample 114 to the test area 124 .

FIGS. 5A and 5B show graph implementations of a camera-specific transform function 165. In particular, in these graphs, the exposure level or light intensity I, in particular the intensity of the incident light, can be shown on the x-axis, and the corresponding color or reflectance R, in particular the value of the color channel of a certain color, for example from one or more of R, G and B can be shown on the y-axis. As an example, the same camera-specific transform function 165 can be shown in FIGS. 5A and 5B. However, in FIG. 5A, the x-axis can show light intensity I on a linear scale of light intensity values in arbitrary units, while in FIG. the transformation shown in the graphs can be mathematically described as follows

As an example, the inverse function of the non-linear function (2) can be mathematically described as follows

Figures 6 and 7 illustrate flowcharts of a detection method for determining at least one analyte in at least one sample 114. The detection method includes step a) (denoted by reference numeral 166) of providing at least one mobile device 112, containing at least one camera 118 and at least one light source 120. As an example, the mobile device 112 illustrated in FIG. 1 may be provided. Further, the determination method includes step b) (denoted by reference numeral 168) of providing at least one test strip 116 containing at least one test field 124, wherein the test field 124 contains at least one test chemical 126 for performing an optical detection reaction in the presence of the analyte. In particular, the test strip 116 illustrated in FIG. 1 may be provided as an example. In addition, the determination method may include step c) (denoted by reference numeral 170) of applying at least one sample 114 to the test field 124. As an example, step c) may be performed by dropping the sample 114 on the test field 124, as illustrated in figures 1 and 2.

In addition, the determination method includes step d) (denoted by the reference position 172) of obtaining a set of images 142 of at least one area 144 of the test strip 116, and the area 144 contains at least a part of the test field 124, on which the sample 114 is applied. Step d) of the method further includes at least the following substeps:

d1) (denoted by the reference position 174) obtaining at least one image 142 before applying the sample 114 to the test field 124 with the light source 120 turned off;

d2) (denoted by reference numeral 176) obtaining at least one image 142 before applying the sample 114 to the test field 124 with the light source 120 turned on; And

d3) (denoted by reference numeral 178) obtaining at least one image 142 after applying the sample 114 to the test field 124.

In particular, substep d1) may, for example, be executed in time period t ₂ ' of the graph shown in FIG. 4B. In addition, substep d2) may, by way of example, be performed in one or both of the time periods t ₁ ' and t ₃ '. It is also possible to perform substep d2) at the beginning of the time period t ₄ ', for example within 16 ≤ t < 32 s, eg before performing step e) of applying the sample 114 to the test field 124, for example within 32 ≤ t < 38 s. In addition, substep d3) can in particular be carried out after the application of the sample 114 to the test field 124, for example, at the end of the time period t ₄ ', for example within 38≤t<58 s and/or the time periods t ₅ ', t ₆ ', t ₇ ' and t ₈ '.

The determination method further includes step e) (denoted by reference numeral 180) of determining the concentration of the analyte in the sample 114 using the images 142 obtained in step d). As illustrated in FIG. 7, the determination method may further include step e) (denoted by reference numeral 182) of comparing respective images obtained in step d) with light source 120 on and off, and determining light intensity differences. The result of step e) may, for example, be used to determine the analyte concentration in sample 114, thus, by way of example, step e) may include step e) as illustrated in FIG.

As further illustrated in FIG. 7, step e) may, for example, include the following sub-steps:

e1) (denoted by reference numeral 184) obtaining at least one element of information about the color of the part of the test field on which the sample is applied for each image to be compared;

e2) (denoted by reference numeral 186) converting a color information item into at least one light intensity information item using at least one camera-specific conversion function 165;

e3) (denoted by reference numeral 188) determining light intensity differences using the light intensity information elements of the respective images with the light source on and off.

As an example, the camera-specific transform function 165 that can be used in substep e2) can, for example, be illustrated in FIGS. 5A and 5B. Thus, the following shows an exemplary calculation that can be performed when carrying out the determination method. The image 142 obtained in step d1) may, for example, have a color or reflectance R _d1 =230, and the image 142 obtained in step d2) may, for example, have a color or reflectance R _d2 =80. As an example, R _d1 and R _d2 may consist of the color information element obtained in step e1). For example, in step e2), the inverse camera-specific transform function (2) can be used to convert R _d1 and R _d2 to light intensities I _d1 =80 and I _d2 =15. Subsequently, in step e3), the light intensity difference can be determined, for example I _d12 =80-15=65. In particular, for step e), the light intensity differences, for example, can be converted to color information element differences for the respective images using the inverted function (2) of the camera-specific conversion function (1). Thus, as an example, R _d12 (I _d12 =65)=211 can be calculated. In particular, color information element differences, such as R _d12, may, for example, contain information about the true color of the test field, such as, for example, the color of the reference field without interference from external or ambient light, before sample 114 can be applied. to test field 124.

After applying the sample 114 to the test area, for example after step c), step d3) can be performed. In particular, step d3) may, for example, include substep d3i) (denoted by reference numeral 190) of obtaining at least one image 142 with the light source 120 turned off; and substep d3ii) (denoted by 192) of obtaining at least one image 142 with the light source 120 turned on. As an example, the images 142 obtained in step d3) may have a color or reflectance R _d3i =190 and R _d3ii =15. As an example, R _d3i and R _d3ii may consist of the color information element obtained in step e1). Again, by way of example, using the inverted function (2) of the camera-specific transform function (1), one can determine the respective light intensities I _d3i =51 and I _d3ii =7, for example in step e2), resulting in a light intensity difference I _d3 =44. Then, for example, you can calculate R _d3 (I _d3 =44)=176. R _d3 , for example, may contain information about the true color of the test field 124 after the test chemical 126 has been reacted to determine the color change. Thus, the color change, in particular the color difference due to the concentration of the analyte in the sample 114, regardless of the incident or ambient light, can, for example, be determined by the difference between R _di2 and R _d3 .

List of reference positions

110 - set

112 - sample

114 - mobile device

116 - test strip

118 - camera

120 - light source

122 - processor

124 - test field

126 - test chemical

128 - ambient light source

130 - holder

132 - bearing element

134 - wetting layer

136 - filter layer

138 - first side

140 - second side

142 - image

144 - region

146 - reference field

148 - the first color of the test field

150 - the second color of the test field

152 - the third color of the test field

154 - color of the reference field

156 - the first color of the reference field

158 - the second color of the reference field

159 - color transition

160 - the first color of the test field

162 - the second color of the test field

164 - the third color of the test field

165 - camera-specific conversion function

166 - step a)

168 - step b)

170 - step c)

172 - step d)

174 - step d1)

176 - step d2)

178 - step d3)

180 - step e)

182 - step e)

184 - step e1)

186 - step e2)

188 - step e3)

190 - step r3i)

192 - step d3ii)

Claims (31)

1. A method for determining at least one analyte in at least one sample (114), including: a) providing at least one mobile device (112) containing at least one camera (118) and at least one light source (120); b) providing at least one test strip (116) containing at least one test field (124), wherein the test field contains at least one test chemical (126) for performing an optical detection reaction in the presence of an analyte; c) applying at least one sample (114) to the test field (124); d) obtaining a set of images (142) of at least one area (144) of the test strip (116), moreover, the area (144) contains at least a part of the test field (124) on which the sample (114) is applied, including: d1) obtaining at least one image (142) before applying the sample (114) to the test field (124) with the light source (120) off; d2) obtaining at least one image (142) before applying the sample (114) to the test field (124) with the light source (120) turned on; And d3) obtaining at least one image (142) after applying the sample (114) to the test field (124), while step d3) includes: g3i) obtaining at least one image (142) with the light source (120) off; And d3ii) obtaining at least one image (142) with the light source (120) turned on; e) determination of the analyte concentration in the sample (114) using the images (142) obtained in step d); characterized in that the method further comprises: e) comparison of the corresponding images obtained in step d), with the light source (120) on and off, and determining the differences in light intensities, while step e) includes: e1) obtaining at least one element of information about the color of the part of the test field (124), on which the sample (114) is applied, for each image (142) to be compared; e2) converting the color information element to at least one light intensity information element using at least one camera-specific conversion function (165); e3) determining the light intensity differences using the light intensity information elements of the respective images with the light source (120) on and off, wherein step e) involves applying the result of step e) to determine the concentration of the analyte in the sample (114). 2. The method according to claim 1, wherein in step e) the light intensity differences are converted into color information element differences for the respective images using the inverse function of the camera-specific conversion function (165), wherein the camera-specific function (165 ) transform is a non-linear function that converts a color information element into a light intensity information element. 3. The method according to claim 1 or 2, characterized in that step e) further comprises applying a light intensity difference between the images (142) obtained in steps d3i) and d3ii). 4. The method according to any one of paragraphs. 1-3, characterized in that in step c) the sample (114) is applied to the test field (124) from the side opposite to the chamber (118). 5. The method according to claim 4, characterized in that the holder (130) is used to position the test strip (116) relative to the mobile device (112), while the test strip (116) is positioned so that the test field (124) was at a distance from the camera (118), while the camera (118) is located on the first side (138) of the test field (124), and the sample (114) is applied on the second side (140) opposite the first side (138). 6. The method according to claim 5, characterized in that the holder (130) is open on the second side (140) in such a way that the test field (124) is uncovered on the second side (140), while the holder (130) contains an opening in such a way that the test field (124) is uncovered on the first side (138). 7. The method according to any one of paragraphs. 1-6, characterized in that the test field (124) is at least partially translucent, while in step e) the effect of ambient light falling through the test field (124) on the camera (118) is determined. 8. The method according to any one of paragraphs. 1-7, characterized in that the test strip (116) additionally contains a reference field (146), while the area (144) of the test strip (124) additionally contains at least a part of the reference field (146), while the reference field (146) is opaque, while step d) of the method further includes: step d4) obtaining at least one image (142) of the reference field (146), and the image (142) of the reference field (146) is taken into account in step e) . 9. A computer-readable storage medium with a computer program stored therein, containing software tools for performing at least step d), step e) and step e) of the method according to any one of paragraphs. 1-8 when executing a computer program on a computer or on a computer network. 10. Mobile device (112), containing: I) at least one chamber (118); ii) at least one light source (120); And III) at least one processor (122), wherein the mobile device (112) is configured to implement a method for determining at least one analyte in at least one sample (114) according to any one of paragraphs. 1-8 in combination with a test strip (116) containing at least one test field (124), wherein the test field (124) contains at least one test chemical (126) for performing an optical detection reaction in the presence of an analyte. 11. A kit (110) for determining at least one analyte in at least one sample (114), moreover, the kit (110) contains a mobile device (112) according to claim 10, moreover, the kit (110) additionally contains at least one a test strip (116) containing at least one test field (124), wherein the test field (124) contains at least one test chemical (126) for carrying out an optical detection reaction in the presence of an analyte.

Images