RU2797009C2 - Devices and method for measuring analyte concentration in physiological fluid sample - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: group of inventions relates to the field of measuring analyte concentration in a sample of physiological fluid. An optical test strip for measuring the concentration of an analyte in a blood sample contains a) a carrier element of the test strip containing a transparent area; b) a test field, wherein the test field comprises at least one carrier element film, wherein the carrier element film is attached to the test strip carrier and covers a transparent area of the test strip carrier; contains at least one test chemical deposited on the carrier element film, wherein the test chemical is configured to carry out an optically detectable determination reaction with an analyte. The test chemical is further configured to partially absorb light having at least one absorption wavelength λ_absorb in the range of 650 nm < λ_absorb ≤ 1,100 nm; and contains at least one porous material for at least partially filtering out the solid components contained in the sample. The carrier element film comprises at least one wavelength filter component configured to substantially block light having wavelengthsλ _block constituting 10 nm ≤ λ_block ≤ WL_lower, with 550 nm ≤ WL_lower ≤ 650 nm. Also a method for measuring the concentration of an analyte in a blood sample and a kit for measuring the concentration of an analyte in a blood sample are disclosed.

EFFECT: group of inventions reduces the impact of ambient light when determining or measuring the concentration of an analyte in a sample of physiological fluid without the need to use additional equipment.

11 cl, 7 dwg

Description

FIELD OF TECHNOLOGY

The present invention relates to an optical test strip, as well as a kit for measuring the concentration of an analyte in a sample of physiological fluid. This invention also relates to a method for measuring the concentration of an analyte in a sample of physiological fluid, optical test strips, kits and methods according to the present invention, which can be used in medical diagnostics to quantify or qualitatively determine and / or measure the concentration of one or more analytes in one or more bodily fluids. However, other applications of the present invention are practically possible.

BACKGROUND OF THE INVENTION

In the field of medical diagnostics, in many cases it is necessary to determine and/or measure the concentrations of one or more analytes in samples of bodily fluids 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.

US 2006/0051738 A1 describes dry reagent diagnostic tests that can react with a single drop of whole blood and provide data on both glucose and light-scattering analytes such as chylomicrons. Such dry reagent tests may use electrochemical detection techniques, optical detection techniques, or both. These tests alert diabetics to excessive levels of postprandial lipemia caused by a diet high in fat, and thus may help reduce the risk of cardiovascular complications in diabetic patients.

US 2018/0172591 A1 describes an optical biosensor. The optical biosensor contains: a substrate; a photosensor located on the substrate and generating an electrical signal when irradiated with light; and a layer of a biological sample located on the photosensor and containing the target substance to be analyzed, and an induction material emitting light by fluorescence, extinction or luminescence when irradiated with light, while the photosensor is irradiated with light emitted by the induction material through fluorescence, extinction or luminescence. The optical sensor detects the spectrum of the biological sample modified by light through the photo-sensor when irradiated with light, and converts the modified spectrum into an electrical signal, thereby enabling the analysis of the biological sample without the use of a separate detector.

US 2005/0109951 A1 describes a device, system and method for fluorescent detection using a portable device. The portable device of the present invention is characterized by low power light, wherein the wavelength range is defined as at least one wavelength of light. The light source is preferably highly energy efficient so that most of the electricity consumed is then converted into transmitted light. The light emitted from the excited fluorophore is preferably detected using any inexpensive, low power photodetector. Although it is not necessary to use a highly sensitive optical detector, fluorescence is preferably detected using any photosensitive device, such as, for example, a conventional photodiode or charge-coupled device (CCD) sensor.

WO 2013/158505 A1 describes enzyme-based diagnostic testing systems for detecting and quantifying at least one of an activity level or concentration of an enzyme or a biochemical analyte in a biological sample. Such enzyme-based diagnostic testing systems can provide fast, accurate, and affordable laboratory quality testing at the point of care. An enzyme-based diagnostic testing system may comprise an immunochromatographic assay cassette that is configured to analyze the amount or activity of an enzyme in a sample, or to enzymatically determine the concentration of an enzyme support in a sample. In addition, enzyme-based diagnostic testing systems may include testing devices (eg, a smartphone or similar remote computing device) having data acquisition and data analysis capabilities. Such test devices may also include automated data reporting and decision support.

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.

Typically, one or more optically detectable changes in the tested chemical composition are monitored to determine the concentration of at least one analyte to be determined based on these changes. Various types of detectors are known in the art to determine at least one change in the optical properties of a test chemical composition. Recently, consumer electronics such as mobile phones, laptops, smartphones and other portable devices have become popular and are used as detectors to detect changes in the chemical composition being tested. In addition to using consumer electronics to detect changes in the optical properties of the test chemistry of conventional test strips, it is also known in the art to obtain information from specially designed test modules using consumer electronics, such as the camera of a portable device. Thus, US 2017/0343480 A1 describes a method for measuring blood glucose levels with a portable 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.

However, despite the advantages associated with using consumer electronics to measure analyte concentration in body fluid samples, a number of technical challenges remain. In particular, ambient light can significantly affect the light detected by the camera of a mobile device, such as a smartphone camera. Thus, it is usually necessary to take into account the effect of ambient light on a given analyte concentration, which currently requires complex combinations of lighting devices, additional communication devices and specially designed test strips, such as, for example, known from US 2017/0343480 A1. In particular, the general approach based on considering the effects of ambient light through the use of additional equipment usually leads to significant inconvenience to the user and an increase in financial costs.

Problem to be solved

Therefore, it is desirable to provide devices and methods that solve the above technical problems of analytical measurements. In particular, an optical test strip, kit and method should be provided that reduce the effect of ambient light in determining or measuring the concentration of an analyte in a body fluid sample without the need for additional equipment.

SUMMARY OF THE INVENTION

This problem is solved by using an optical test strip, a kit and a method for measuring the concentration of an analyte in a sample of physiological fluid 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 usually 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 non-optional features of the present invention.

In the first aspect, an optical test strip is described for measuring the concentration of an analyte in a sample of physiological fluid. The optical test strip contains a test strip carrier containing a transparent area and a test field. The test field contains at least one carrier element film, at least one test chemical applied to the carrier element film, and at least one porous material.

As used herein, the term "optical 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. This term, in particular, may, without limitation, refer to an arbitrary element configured to measure the concentration of an analyte in a sample of physiological fluid. The optical test strip may in particular be configured to carry out a color change detection reaction and thus provide optically detectable information about the analyte concentration. For example, the optical test strip may be specifically shaped like a strip, thus the test strip may be long and narrow.

As used herein, the term "analyte" 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 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, the term "measurement of the concentration 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 the measurement, for example, may be the concentration of the analyte and/or the presence or absence of the analyte to be measured. Specifically, as an example, the measurement may be a blood glucose measurement, thus the result of the measurement may be, for example, a blood glucose concentration.

As used herein, the term "test strip carrier" is a broad term, and its usual 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 an arbitrary substrate, made with the possibility of providing a means of stabilizing the optical test strip, in particular, the test field. The carrier element of the test strip may in particular be in the form of a strip, for example in the form of a rectangular strip. For example, the test strip carrier may be flexible and/or deformable. For example, the test strip carrier may have a width, such as a side extension perpendicular to the longitudinal axis of the test strip, from 1 mm to 20 mm, for example from 2 mm to 5 mm. The test strip carrier may have a length, such as a longitudinal extension, of 10 mm to 70 mm, such as 15 mm to 50 mm. The specified length may exceed the specified width, for example, at least 1.5 times. The test strip carrier may have a thickness of 100 µm to 2 mm, for example 500 µm to 1 mm. The test strip carrier may be wholly or partly made of at least one material, such as one or more of plastic material, ceramic material, or paper. In particular, the carrier element of the test strip may be wholly or partly made of at least one plastic film. The carrier element of the test strip may be made from a single layer or from a plurality of layers. In particular, the test strip carrier may be opaque, eg comprise at least one material completely or partially opaque to visible light.

The test strip carrier includes at least one transparent area, such as, for example, an area entirely or partially made of a translucent material, or an area containing at least one hole, notch or slot in the test strip carrier. For example, the transparent region may be circular, oval, or polygonal in shape. For example, the transparent region may be completely or partially surrounded by an impermeable or opaque test strip support material. For example, the transparent area may define at least one window, in particular a window opening, in the test strip carrier. The window or window opening, in particular, as will be described in more detail below, may be completely or partially covered by the test field, which, for example, can be applied to the carrier element of the test strip in the area of at least one transparent area, thus, for example, covering at least the window. However, the transparent area may, for example, extend over the entire test strip, for example completely cover the test strip. Thus, in particular, the test strip carrier itself can, for example, be entirely made of a transparent material and can therefore, for example, itself be a transparent region.

As used herein, the term "test field" is a broad term and its common and accepted meaning should be left to those skilled in the art and should not be limited to a special or individual meaning. The term, in particular, may refer, without limitation, to an arbitrary element containing at least one amount of a test chemical for determining at least one analyte. The test field, for example, may contain at least one layer containing the test chemical. As an example, the test field may contain an arbitrary layered element having a layered structure, and the test chemical consists of at least one layer of the layered structure. In particular, the term may refer to a coherent amount of a test chemical, such as a field, such as a circular, polygonal, or rectangular field, containing one or more layers of material, with at least one test field layer, such as a carrier film containing it is a test chemical. Other layers may be present to provide distribution properties for distributing the sample, or to provide separation properties, for example to separate particulate sample components such as cellular components, for example by containing at least one porous material.

In particular, the test field contains at least one porous material, for example a completely or partially porous material, for at least partially filtering the solid components contained in the sample. The porous material, in particular, can be configured to separate the particulate components of the sample or the solid components of the sample. Thus, the porous material, in particular, may be or may contain a filter material, such as, for example, titanium dioxide (TiO2). In particular, the porous material may, for example, filter out cellular components contained in a sample of physiological fluid.

In addition, the test field contains at least one carrier element film. At least one test field carrier film is applied to the test strip carrier and covers the transparent area of the test strip carrier. Thus, the carrier film may, for example, cover or cover a transparent area, such as a hole or slot, of the test strip carrier. In particular, the carrier film may be or contain a material having an inherent rigidity to be suitable for covering a transparent area, such as a hole or slot, of the test strip carrier.

As used herein, the term "carrier film" 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 an arbitrary film-like material. In particular, the carrier film may be in the form of a film, wherein the carrier film in the first extension direction may be at least ten times smaller than the extension of the carrier film in the other direction, extending perpendicular to the first direction. In particular, the film of the support element may be made of at least one flexible or deformable material, such as at least one flexible or deformable plastic film. The plastic film, by way of example, may have a thickness of 10 µm to 500 µm. The carrier film may in particular comprise at least one transparent matrix material, such as at least one transparent plastic material which is translucent in the visible spectral range. Examples will be given in more detail below.

In particular, the carrier film may have a complex structure, such as a layered structure, containing one or more layers of material. Thus, the film of the carrier element, in particular, may contain at least one layer of a transparent matrix material. Other layers may be present, for example adhesive layers such as adhesive layers, adhesive tape layers or other bonding layers.

The carrier film further comprises at least one wavelength filter component that is configured to substantially block light having a wavelength λ _block of λ _block ≤ WL _lower , with 550 nm ≤ WL _lower ≤ 650 nm. In particular, WL _lower refers to a wavelength indicative of at least one wavelength filter component. As used herein, the term "light" is a broad term, and its usual and conventional 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 electromagnetic radiation having wavelengths within the spectrum of electromagnetic radiation. In particular, the term "light", referred to hereinafter, may represent or include electromagnetic radiation with wavelengths _λe at least in the range of 10 _nm≤λe ≤200 nm, in particular 100 _nm≤λe ≤1200 nm , more specifically 250 _nm≤λe ≤1200 nm, even more specifically 400 _nm≤λe ≤1200 nm.

In particular, the wavelength filter component can, for example, be introduced or mixed within the matrix material of the carrier film, for example the transparent matrix material of the carrier film, in particular within at least one layer of the carrier film. Additionally or alternatively, the wavelength filter component may be implemented in the matrix material, being one or more dispersed in the matrix material or chemically bonded to the matrix material, such as by covalent bonding, chemical complexing, or ionic bonding. Additionally or alternatively, the wavelength filter component may also form at least one filter layer, such as at least one layer located on one or both sides of at least one layer of matrix material.

As used herein, the term "substantially blocks" 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 to, without limitation, the process of stopping or blocking the transmission of most of the electromagnetic radiation through the material. In particular, a wavelength filter component having a characteristic wavelength WL _lower and configured to substantially block light having wavelengths λ _block , may in particular be configured to perform one or both of the following functions: absorption or reflection ≥ 80% of the intensity of electromagnetic radiation having wavelength λ _block ≤WL _lower as a result of transmission or passage through the carrier element film. Thus, a wavelength filter component having a characteristic wavelength WL _lower and configured to substantially block light with wavelengths λ _block can in particular be configured to transmit less than 20%, in particular less than 10%, more specifically less than 5% light with wavelengths λ _block ≤WL _lower through the carrier film. Said transmission may be defined as a measure of the intensity of light, such as electromagnetic radiation, passed through a filter divided by the initial intensity of light incident on the filter multiplied by 100%.

The blocking effect of at least one wavelength filter component can be based on various physical principles. Thus, by way of example, the wavelength filter component may comprise at least one filter material suitable for absorbing light, in particular wavelength selectively, such as at least one dye, for example at least one organic or inorganic dye. . A filter material, such as at least one dye, for example, can be introduced into at least one matrix material, such as as described above. Additionally or alternatively, the filter material can also consist of at least one filter layer, for example at least one layer of filter material, directly or indirectly applied to one or both sides of the carrier element film. Furthermore, in addition to absorption or as an alternative to absorption, the blocking effect can also be achieved by reflection, for example wavelength selectively. Thus, by way of example and as will be described in more detail below, the wavelength filter component may comprise at least one multilayer structure comprising a plurality of layers having different optical refractive indices. Thus, by way of example, the wavelength filter component may comprise at least one interference filter, such as at least one interference filter comprising a plurality of layers of at least one organic or inorganic material, the layers having a changing refractive index, such as periodically changing refractive index. The layer structure, for example, can be applied directly or indirectly to the carrier film on one or both sides. Additionally or alternatively, the carrier element film itself may be part of a wavelength selective element. Combinations of the mentioned possibilities are practically possible.

The test field additionally contains at least one test chemical, directly or indirectly applied to the carrier element film. The test chemical is configured to conduct an optically detectable determination reaction using an analyte. 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, may 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. 20 Hönes et al: Diabetes Technology and Therapeutics, Vol. 10, Supplement 1, 2008, pp. 10-26. However, other test chemicals are practical.

The test chemical is additionally configured to partially absorb light having at least one absorption wavelength λ10Gl in the range of 650 nm<1100 nm. In particular, light having at least one absorption wavelength λ _absorb can in particular be completely or partially absorbed by the test chemical. As used herein, the term "absorb" is a broad term, and its usual and conventional 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 process of absorption of energy by a substance, such as the electrons of an atom. Thus, in particular, the electromagnetic energy of light having at least one absorption wavelength _λabs can be at least partially absorbed by the test chemical and thus, for example, be converted into internal energy of the test chemical. Thus, for example, a test chemical, in particular, may have an extinction or attenuation coefficient α>0.

As _an example, for _the blocking wavelength _λblock component of a wavelength filter configured to substantially block light having wavelengths _λblock , the following can _be specifically applied: WL _lower , 250 nm≤λ _block ≤WL _lower or 400 nm≤λ _block ≤WL _lower . Thus, in particular, the wavelength filter component can be configured to substantially block all light from the ultraviolet range down to WL _lower . In particular, the wavelength filter component may, for example, be configured to substantially block ultraviolet (UV) light, such as electromagnetic radiation in the UV range, as well as visible light, in particular electromagnetic radiation visible to the human eye, below or constituting the WLHM.

In particular, the wavelength filter component may be positioned within the carrier film. In particular, the wavelength filter component may, for example, be dispersed within the carrier film, eg blended within the material of the carrier film.

As an example, the wavelength filter component may be selected from the group consisting of a long wavelength pass filter component and a band pass filter component. In particular, the wavelength filter component in particular may be or comprise a long wavelength transmission filter, for example the wavelength filter component may be configured to substantially block light with wavelengths λ _block ≤ WL _lower . Alternatively, the wavelength filter component may be or comprise a band pass filter. The band pass filter in particular may be or comprise a combination of a long pass filter and a short pass filter and thus only pass light within a predetermined wavelength range, for example only within the light range. Thus, in particular, the wavelength filter component can further be configured to block light with wavelengths λ _block ≥WL _top . In particular, WL _high may refer to an additional wavelength further characterizing at least one wavelength filter component. As an example, the wavelength filter component may be configured to substantially block light, for example, having wavelength WL _up and above, as well as light having wavelengths WL _low and below.

In particular, the wavelength filter component can in particular be or comprise at least one long wavelength transmission filter. A long-wavelength transmission filter, in particular, may have a passband edge that rises with the wavelength of the light. Thus, a long-wavelength transmission filter in particular can exhibit higher light transmission as the wavelength is longer. In particular, the transmission of light through a long wavelength transmission filter can increase with increasing wavelength. In addition, the long-wavelength transmission filter may have a characteristic wavelength _λdvp . Thus, WL _lower can equal λ _dvp . In particular, the transmission T _dvp of the long-wavelength transmission filter per λ _dfp may be 50% of the maximum T _dvp transmission of the long-wavelength transmission filter. Thus, the characterizing wavelength _λtdt can be determined in such a way that _Ttdt transmission of the long-wavelength transmission filter at _λtdt can be 50% of the maximum _Ttdtmax transmission of the long-wavelength transmission filter. In particular, as an example, if a long-wavelength pass filter, for example, in its transmission range, has a maximum transmission of 85%, the characteristic wavelength _λdvp for this case is defined as the wavelength at which the long-wavelength pass filter achieves a transmission of 0.5×85 %=42.5%, for example, when considering the transmission spectrum with increasing wavelengths. In particular, the maximum transmission of the long-wavelength transmission filter can be, for example, at least 75%, in particular at least 80%, more specifically at least 85% or even at least 90% or at least 95%.

In addition, the long-wavelength transmission filter may have a slope S _dvp rising edge of the passband. In particular, this may be advantageous when the long-wavelength pass filter has a steep passband edge to block or absorb the maximum portion of light with wavelengths below _λdvp and the maximum portion of light with wavelengths greater than or above _λdvp . The slope of a long-wavelength transmission filter can usually be expressed in units of electron volts (eV) and defined as follows:

In equation (1), λ _block may specifically represent that wavelength at and below which the long wavelength transmission filter substantially blocks light. Thus, at the wavelength λ, the transmission _block T _dvp of the long-wavelength transmission filter can in particular be less than 20%, in particular less than 10%, more particularly less than 5%. In addition, λ _prop can be defined as the wavelength at which and above which the long-wavelength transmission filter reaches a value of 95% of the maximum transmission T _TDRmax of the long-wavelength transmission filter. Thus, at wavelengths less than _λprop T _dvp transmission of a long-wavelength transmission filter can be <95% of the maximum T _dvpmax transmission of a long-wavelength transmission filter, and at wavelengths equal to or above λ _prop , T _dvp transmission can be ≥95% T _dvp transmission, for example from 95% to 100% T _DVPmax . If, for example, a long-wavelength transmission filter, more specifically in the transmission region, has a maximum transmission of 85%, λ _prop can be defined as the wavelength at which, for example, as the wavelength increases, the transmission reaches a value of 0.95×85%=80, 75%. In addition, in the long-wavelength filter slope formula above, the parameter h is Planck's constant (h≈6.626⋅10 ^-34 J⋅s) and c is the speed of light in vacuum (s≈3.0⋅10 ⁸ m/s) . With the slope defined in this way, in particular, the slope S _dvp may, for example, be 0 eV < S _dvp ≤1.2 eV, in particular 0.1 eV ≤ _{S dvp} ≤1.1 eV, more specifically 0.2 eV ≤S _dvp ≤0.9 eV.

In particular, the characterizing wavelength WLHM characterizing at least one component of the wavelength filter may, for example, be in the range 550 nm≤WLlow _≤650 nm, in particular in the range 600 _nm≤WLlow ≤650 nm, more specifically in the range of 625 nm≤WL _lower ≤650 nm.

The test field of the optical test strip may in particular have a shape selected from the group consisting of: a rectangular shape; square shape; round shape; ring shape. In addition, the test field may contain at least one spreading layer. In particular, the spreading layer may be configured to evenly distribute or spread the bodily fluid sample over the surface of the test field on which the sample may be applied.

The wavelength filter may, for example, comprise an interference filter, in particular a high pass interference filter. As used herein, the term "interference filter" 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 term particularly may refer to, without limitation, an optical filter that reflects one or more spectral bands or lines and transmits others while maintaining near-zero absorption for all wavelengths of interest. As an example, the interference filter may contain several layers of dielectric material with different refractive indices. In particular, the interference filter has the properties of wavelength selectivity. Thus, by way of example, a high-pass interference filter having a characteristic wavelength λ _HPF , also referred to as a cutoff frequency, can selectively block or attenuate all light having wavelengths below λ _HPF , while the high-pass interference filter can pass all light. , having wavelengths above λ _PFHP .

In particular, the interference filter may be located on at least one surface of the carrier element film. By way of example, the interference filter may be applied directly or indirectly to the upper surface of the carrier film, for example as a separate layer. Additionally or alternatively, the interference filter may be applied directly or indirectly to the bottom surface of the carrier film. Thus, the interference filter can be located, for example, both on the top and on the bottom surface of the carrier film.

In addition, the optical test strip, in particular the carrier film, may contain at least one additional filter component. In particular, at least one additional filter component may comprise a short wavelength transmission filter. In particular, the short-wavelength transmission filter may comprise a passband edge incident with the wavelength of the light. Thus, a short wavelength transmission filter in particular can exhibit an increase in light transmission as wavelengths decrease. In particular, the transmission of light through a short-wavelength transmission filter may decrease with increasing wavelength. In addition, the short-wavelength transmission filter may have a characteristic wavelength λ _TRC , while λ _TRC may be equal to WL _bepx . In particular, the transmission T _CTF of the short-wavelength transmission filter per λ _CTF may be 50% of the maximum transmission T _CTFmax of the short-wavelength transmission filter. For example, the characteristic wavelength λ _CRT of a short-wavelength transmission filter may be in the range of 630 nm≤λ _CRT ≤800 nm, in particular in the range of 640 nm≤λ _CRT ≤680 nm.

By way of example, the additional filter component, in particular the short wavelength transmission filter, may be or comprise a short wavelength transmission interference filter. In particular, the short wavelength transmission interference filter, for example, may be an interference filter as defined above. In particular, the shortwave transmission interference filter may comprise several layers of dielectric material having different refractive indices. In particular, the short wavelength transmission interference filter may also have wavelength selective properties. Thus, by way of example, a short wavelength transmission interference filter may have a characteristic wavelength λ _CFT and may selectively block or attenuate all light having wavelengths above λ _CFT , while the short wavelength transmission interference filter may pass all light having wavelengths below λ _CVPF .

The optical test strip, in particular the carrier film, may, for example, contain a combination of filter components. For example, the optical test strip may comprise a combination of a long wavelength transmission filter and a short wavelength transmission filter, such as a high pass interference filter and a short wavelength transmission interference filter. However, other combinations of filters are practically possible.

In particular, the additional filter component can be configured to substantially block the transmission of light having wavelengths λ≥WL _bepx , where WL _bepx >WL _lower , in particular WL _bepx ≥WL _lower +20 nm, more specifically WL _bepx ≥WL _lower +30 nm, e.g. WL _lower +20 nm≤WL _bepx ≤WL _lower +60 nm, e.g. WL _lower +30 nm≤WL _upperx ≤WL _lower +50 nm.

In particular, the carrier element film, for example, may comprise at least one material selected from the group consisting of: a thermoplastic material; polyethylene terephthalate (PET); polyethylene glycol (PEG); polycarbonate (PC), in particular Pokalon®; polypropylene (PP), polystyrene (PS). Further, by way of example, the test strip carrier may comprise at least one material selected from the group consisting of: plastic material; thermoplastic material; polycarbonate, in particular Makrolon® or Lexan®®.

For example, the optical test strip may further comprise at least one reference color field. As used herein, the term "reference color field" 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 an arbitrary two-dimensional area that has a predetermined color with known properties. In particular, the reference color field, for example, may contain at least one white field, such as a field having a white color. In addition, the reference color field may have a shape selected from the group consisting of: a rectangular shape; square shape; round shape; ring shape.

In particular, a reference color field, for example, may be used as a reference. In particular, when determining the concentration of an analyte in a sample applied to a test field, the color of the reference color field can be used as a reference for comparison with an optically determined test chemical determination reaction with an analyte.

In a further aspect of the present invention, a method is described for measuring the concentration of an analyte in a sample of physiological fluid applied to the test field of an optical test strip using a mobile device. The method includes the following method steps, which may be performed in a given order. However, another order is practically possible. In addition, one, more than one, or even all of the steps of the method may be performed once or repeatedly. In addition, the method steps may be performed sequentially or, alternatively, two or more method steps may be performed in an overlapping manner or even in parallel. The method may further include additional method steps that are not listed.

The method includes the following steps:

i) providing an optical test strip comprising at least one wavelength filter component that is configured to substantially block light having wavelengths λ _block of λ _block ≤ WL _lower , wherein 550 nm ≤ WL _lower ≤ 650 nm;

ii) providing a mobile device, wherein the mobile device comprises a camera and a wavelength filter, wherein the wavelength filter is configured to substantially block the transmission of light having wavelengths λ of 1200 nm≥λ≥WL _bepx , wherein 800 nm≤WL _vepx ≤1000 nm;

iii) applying a sample of physiological fluid to the test field;

iv) obtaining an image of the test field containing the sample applied to it, using the camera of the mobile device; And

v) determining the concentration of the analyte in the body fluid sample applied to the test field by evaluating the optically detectable test chemical detection response of the test field.

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 may specifically refer to, without limitation, a mobile electronics device, more specifically a mobile communication device such as a cellular phone or smartphone. Additionally or alternatively, a mobile device may also refer to a tablet computer or other type of portable computer containing at least one camera.

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. As used herein, without limitation, the term “image” specifically may refer to data recorded by a camera, such as a collection of electronic readings from an imaging device, such as pixels of a camera chip. Thus, the image itself may contain pixels, the pixels of the image being correlated with the pixels of the camera chip.

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 yellow (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 options such as R, G, B, as an example, four-color options such as C, M, Y, K can be used. These methods are usually known to a person skilled in the art.

The wavelength filter of the mobile device may be integrated into the camera chip, such as at least one chip with a complementary metal oxide semiconductor (CMOS; complementary metal-oxide-semiconductor) structure. Thus, especially when imaging with a camera of a mobile device, light with wavelengths λ of 1200 nm ≥ λ ≥ _{WL bepx} can be substantially blocked. Thus, in particular when recording images using a mobile device, a wavelength filter with characteristic wavelength WL _vepx can substantially block the recording of light with wavelengths X.

For additional possible definitions of terms and possible embodiments of the invention, reference may be made to the description of the optical test strip above or further described below.

The mobile device may further comprise at least one light source. The light source may in particular be configured to emit light to illuminate an object when it is imaged by the mobile device. In particular, step iv) of the method may further comprise illuminating the optical test strip, in particular the test field, in particular using a light source of the mobile device.

The optical test strip may, for example, contain at least one reference color field. In particular, the method may further include step vi) obtaining at least one image of the reference color field using a mobile device, such as a camera of a mobile device. In addition, step vi) of the method may include illuminating the optical test strip, in particular the reference color field.

In particular, the wavelength filter of the mobile device may in particular comprise at least one short wavelength transmission filter. As an example, a short-wavelength transmission filter in particular may comprise a passband edge incident with the wavelength of the light. Thus, a short wavelength transmission filter in particular can exhibit increased light transmission at shorter wavelengths. In particular, the transmission of light through a short-wavelength transmission filter may decrease with increasing wavelength. In addition, the short-wavelength transmission filter may have a characteristic wavelength λ _TRC . So WL _bepx can equal WL _bepx . Specifically, by way of example, the transmission _Tcfp of the shortwavelength transmission filter per _λCTR may be 50% of the maximum transmission _Tcfmax of the shortwavelength transmission filter.

In particular, the characterizing wavelength WL _bepx , which characterizes at least one wavelength filter of the mobile device, may, for example, be in the range 800 nm≤WL _bepx ≤1000 nm, in particular in the range 800 nm≤WL _bepx ≤950 nm, more specifically 800 nm ≤ WL _vepx ≤ 900 nm.

In particular, the optical test strip may, by way of example, be or comprise an optical test strip as described above or as further described below.

In a further aspect of the present invention, a kit is described for measuring the concentration of an analyte in a physiological fluid sample. The kit contains an optical test strip according to any of the embodiments of the invention, as described above or as described in more detail below, and a mobile device containing a camera. The mobile device further comprises a wavelength filter, wherein the wavelength filter is configured to substantially block the transmission of light having wavelengths X of 1200 nm≥λ≥WL _bepx , with 800 nm ≤ WL _bepx ≤1000 nm.

In particular, the mobile device may further comprise at least one light source. In particular, the at least one illumination source of the mobile device may be configured to illuminate an object, such as an optical test strip, when an image of the object, such as an optical test strip, is acquired by the mobile device.

In addition, the mobile device may contain at least one processor. The processor, by way of example, may be configured to perform steps ii) v) of a method for measuring the concentration of an analyte in a sample of physiological fluid applied to the test field of an optical test strip using a mobile device, as described above or as further described below. In addition, the processor may also be configured to perform step vi) of the method according to the method.

The devices and methods of the present invention can provide many advantages over known methods and devices for measuring the concentration of an analyte in a body fluid sample. Thus, in particular, the present invention can be more independent of ambient lighting conditions than conventional devices and methods. In particular, by way of example, the optically detectable test chemical reaction, in particular the color reaction itself, may vary depending on the spectral range, for example, may vary for different spectral ranges. Thus, the optically detectable detection response may depend on ambient light conditions. However, the present invention can provide devices and methods for reducing the effect of ambient light on an optically detectable detection response, for example, without using an additional color filter as a piece of equipment, such as additional filters for a camera. In particular, by way of example, when analyzing or evaluating calorimetric color strips, such as, for example, optical test strips, for example for blood glucose, using a mobile device, such as a smartphone camera, in particular, compensation for various conditions may be required. ambient light, and, additionally, it may be necessary to take into account various specific properties or characteristics of the camera. As an example, even the light source of the mobile device itself may differ for different types and models of mobile devices, such as smartphones. Also, as an example, the color filters used in RGB channels, such as camera chips, such as CCD or CMOS chips, can vary greatly from camera to camera. The present invention can provide an estimate of the analyte concentration by monitoring the change in the intensity of the test chemical only in a narrowed frequency range. For example, as a result, an analyte concentration estimate may be less dependent on ambient light conditions, such as lighting circumstances, and therefore may be more clearly related to an observed color reaction than with prior art methods and devices.

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

Implementation 1: Optical test strip for measuring the concentration of an analyte in a sample of physiological fluid, containing:

a) the carrier element of the test strip containing at least one transparent area;

b) a test field, while the test field contains:

at least one carrier film, wherein the carrier film is attached to the test strip carrier and at least partially covers a transparent area of the test strip carrier;

- at least one test chemical deposited on the carrier element film, wherein the test chemical is configured to conduct an optically detectable detection reaction with an analyte, wherein the test chemical is additionally configured to at least partially absorb light having at least one absorption wavelength λ _absorbed in the range of 650 nm<λ _absorbed ≤1100 nm; And

- at least one porous material for at least partial filtering of the solid components contained in the sample;

wherein the carrier element film comprises at least one wavelength filter component configured to substantially block light having wavelengths λ _block constituting λ _block ≤ WL _lower , with 550 nm ≤ WL _lower ≤ 650 nm.

Embodiment 2: The optical test strip according to the previous embodiment, characterized in that the wavelength filter component is configured to substantially block light having wavelengths λ _block (146) of 10 nm≤λ _block ≤WL _lower , in in particular 100 nm≤λ _block ≤WL _lower , more specifically 250 nm≤λ _block ≤WL _lower , and more specifically 400 nm≤λ _block ≤WL _lower.

Embodiment 3: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the wavelength filter component is disposed within the carrier film, in particular the wavelength filter component is dispersed within the carrier film.

Embodiment 4: An optical test strip (OD) according to any of the preceding embodiments of the invention, characterized in that the wavelength filter component (121) is selected from the group consisting of a long-wavelength transmission filter component and a band-pass filter component.

Embodiment 5: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the wavelength filter component comprises at least one long wavelength transmission filter, wherein the long wavelength transmission filter comprises a pass band edge rising with the wavelength of light, at in this case, the long-wavelength transmission filter additionally has a characteristic wavelength, λ _dvp , while the transmission of the long-wavelength transmission filter at λ _dvp is 50% of the maximum transmission of the long-wavelength transmission filter, and at the same time WL _lower =λ _dvp .

Embodiment 6: Optical test strip according to the previous embodiment, characterized in that the long-wavelength transmission filter has a slope S _dvp of the rising edge of the passband, while 0 eV≤S _dvp ≤1.2 eV, in particular 0.1 eV ≤ S _dvp ≤1.1 eV, more specifically 0.2 eV ≤ _{S dvp} ≤0.9 eV, while S _dvp =h⋅s⋅[(1/λ _block )-(1/λ _prop )], while at wavelength λ, _{the block} T _dvp transmission of the long-wavelength transmission filter is equal to or less than 5%, while at the wavelength λ _prop T _dvp transmission of the long-wavelength transmission filter is equal to or greater than 95% FROM T _DVPmax .

Embodiment 7: Optical test strip according to any of the preceding embodiments of the invention, characterized in that 600 nm≤WL _lower ≤650 nm, in particular 625 nm≤WL _lower ≤650 nm.

Embodiment 8: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the test field has a shape selected from the group consisting of: a rectangular shape; square shape; round shape; ring shape.

Embodiment 9: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the test field further comprises at least one distribution layer, wherein the distribution layer is configured to evenly distribute or spread the body fluid sample over the surface of the test field, on which the sample is applied.

Embodiment 10: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the wavelength filter component comprises an interference filter, wherein the interference filter has a characteristic wavelength λ _HPF , with WL _lower = λ _HPF.

Embodiment 11: Optical test strip according to the previous embodiment of the invention, characterized in that the interference filter is located on at least one surface of the carrier film, in particular on the upper surface of the carrier film, on the lower surface of the carrier film, or both top and bottom surface of the carrier element film.

Embodiment 12: Optical test strip (OT) according to any of the preceding embodiments of the invention, characterized in that the optical test strip (OT), in particular the film (120) of the carrier element, contains at least one additional filter component, when in this case, at least one additional filter component contains a short-wavelength transmission filter.

Embodiment 13: Optical test strip (PO) according to the preceding claim, characterized in that the additional filter component is configured to substantially block the transmission of light having wavelengths λ≥WL _vepx , with WL _vepx >WL _lower , in particular WL _vepx ≥WL _lower +20 nm, more specifically WL _topx ≥WL _lower +30 nm, such as WL _lower +20 nm ≤WL _vepx ≤WL _lower +60 nm, such as WL _lower +30 nm ≤WL _upper ≤WL _lower +50 nm.

Embodiment 14: An optical test strip according to any of the preceding embodiments of the invention, wherein the carrier film comprises at least one material selected from the group consisting of: a thermoplastic material; polyethylene terephthalate (PET); polyethylene glycol (PEG); polycarbonate (PC), in particular Pokalon®; polypropylene (PP), polystyrene (PS).

Embodiment 15: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the test strip carrier comprises at least one material selected from the group consisting of: plastic material; thermoplastic material; polycarbonate, in particular Makrolon® or Lexan®.

Embodiment 16: An optical test strip according to any of the preceding embodiments of the invention, characterized in that the optical test strip further comprises at least one reference color field.

Embodiment 17: Optical test strip according to the previous embodiment of the invention, characterized in that the reference color field contains at least one white field.

Embodiment 18: An optical test strip according to either of the two preceding embodiments of the invention, characterized in that the reference color field has a shape selected from the group consisting of: a rectangular shape; square shape; round shape; ring shape.

Implementation 19: A method for measuring the concentration of an analyte in a sample of physiological fluid applied to the test field of an optical test strip using a mobile device, including:

i) providing an optical test strip comprising at least one wavelength filter component that is configured to substantially block light having wavelengths λ _block of λ _block ≤WL _lower , wherein 550 nm ≤ WL _lower <650 nm;

ii) providing a mobile device, wherein the mobile device comprises at least one camera and at least one wavelength filter, wherein the wavelength filter is configured to substantially block the transmission of light having wavelengths λ of λ≥WL _vepx , where 800 nm ≤ WL _bepx ≤ 1000 nm;

iii) applying a sample of physiological fluid to the test field;

iv) obtaining at least one image of the test field containing the sample applied to it, using the camera of the mobile device; And

v) determining the concentration of the analyte in the body fluid sample applied to the test field by evaluating the optically detectable test chemical detection response of the test field.

Embodiment 20: The method according to the previous embodiment, characterized in that the wavelength filter (134) is configured to substantially block the transmission of light having wavelengths X of 1200 nm ≥ λ ≥ WL _bepx.

Embodiment 21: A method according to any of the preceding method embodiments, characterized in that the mobile device further comprises at least one illumination source, wherein step iv) of the method further comprises illuminating the optical test strip, in particular by means of mobile device light source.

Embodiment 22: A method according to any of the preceding method embodiments, wherein the optical test strip further comprises at least one reference color field, and the method further comprises step vi) obtaining at least one image reference color field using a mobile device.

Embodiment 23: The method according to the previous embodiment, characterized in that step vi) further comprises illuminating the optical test strip, in particular with the light source of the mobile device.

Embodiment 24: A method according to any of the preceding method embodiments, characterized in that the wavelength filter comprises at least one short wavelength transmission filter, wherein the short wavelength transmission filter comprises a pass band edge incident with the wavelength of the light, with In this case, the short-wavelength transmission filter additionally has a characteristic wavelength λ _SRF , while the transmission of the short-wavelength transmission filter at λ _SRF is 50% of the maximum transmission of the short-wavelength transmission filter, and WL _vepx =λ _SRF.

Embodiment 25: The method according to any of the preceding embodiments of the invention relating to the method, characterized in that 800 nm ≤ WL _vepx ≤ 950 nm, in particular 800 nm ≤ WL _vepx ≤ 900 nm.

Embodiment 26: The method according to any of the preceding embodiments of the invention relating to a method, wherein the optical test strip comprises an optical test strip according to any of the preceding embodiments of the invention relating to an optical test strip.

Embodiment 27: A kit for measuring the concentration of an analyte in a physiological fluid sample, the kit comprising an optical test strip according to any of the preceding embodiments relating to an optical test strip, and the kit further comprising a mobile device, the mobile device comprising: at least one camera, wherein the mobile device further comprises at least one wavelength filter, wherein the wavelength filter is configured to substantially block the transmission of light having wavelengths λ of λ≥WL _vepx , wherein 800 nm≤WL _vepx ≤1000 nm.

Embodiment 28: The set (128) according to the previous embodiment, characterized in that the wavelength filter (134) is configured to substantially block the transmission of light having wavelengths k of 1200 nm ≥ λ ≥ WL _vepx.

Embodiment 29: A kit according to any of the preceding kit embodiments, characterized in that the mobile device further comprises at least one light source.

Embodiment 30: A kit according to any of the preceding kit-related embodiments, characterized in that the mobile device further comprises at least one control unit, in particular at least one processor.

Embodiment 31: A kit according to a previous embodiment, characterized in that at least one processor is configured to perform steps iii) v) of a method according to a method according to any of the previous method embodiments.

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 claims. 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:

in fig. 1 shows an embodiment of an optical test for measuring the concentration of an analyte in a sample of physiological fluid in perspective view;

in fig. 2 shows an embodiment of a kit for measuring the concentration of an analyte in a sample of physiological fluid in perspective view;

in fig. 3 shows an embodiment of an optical test strip in cross-sectional view;

in fig. 4A and 4B show various embodiments of a sectional view of an optical test strip;

in fig. 5A-5C show a plot of the transmission spectra for various embodiments of the wavelength filter components (FIG. 5A), as well as plots of the test chemical (FIG. 5B) and test field (FIG. 5C) reflectance spectra for various blood glucose concentrations;

in fig. 6A and 6B are graphs of red color histograms recorded from an embodiment of a mobile device containing a camera; And

in fig. 7A and 7B show flowcharts of various embodiments of a method for measuring the concentration of an analyte in a sample of physiological fluid applied to the test field of an optical test strip using a mobile device.

DETAILED DESCRIPTION OF THE INVENTION

1, an embodiment of an optical test strip 110 for measuring the concentration of an analyte in a physiological fluid sample 112 is shown in perspective view. The optical test strip 110 includes a test strip carrier 114 comprising at least one transparent area 116. The optical test strip 110 further comprises at least one test field 118 comprising at least one carrier film 120 deposited on the carrier. element 114 of the test strip, and the film 120 of the carrier element contains at least one component 121 of the wavelength filter. Test field 118, further comprising at least one test chemical 122 deposited on carrier film 120, wherein test chemical 122 is configured to conduct an optically detectable detection reaction with an analyte, and at least one porous material 124 for at least partially filtering out the solid components contained in the sample 112. In addition, the optical test strip 110 may contain at least one reference color field 126.

In FIG. 2 shows an embodiment of a kit 128 for measuring the concentration of an analyte in a bodily fluid sample 112 in perspective view. Set 128 contains an optical test strip software and a mobile device 130. Mobile device 130 contains at least one camera 132 and at least one filter 134 wavelength. In addition, mobile device 130 may include at least one light source 136 and at least one processor 138.

3, an embodiment of an optical test strip 110 is illustrated in cross-sectional view. In particular, as illustrated in FIG. 3, the sample 112 can be applied to the first side 140 of the optical test strip 110, in particular to the test field 118, while the optically determined reaction of the determination of the test chemical 122 can be evaluated from the second side 142 of the optical test strip 110, in particular the test fields 118. In FIG. 4A and 4B illustrate various embodiments of a sectional view of an optical test strip 110. FIG. 4A and 4B, in particular, embodiments of enlarged cross-sectional views of the portion of the optical test strip PO indicated by region IV illustrated in FIG. 3 may be shown. In particular, in FIG. 4A and 4B, various implementations of test field 118 can be illustrated.

As illustrated in FIG. 4A and 4B, the film 120 of the test field carrier 118 is applied to the test strip carrier 114 and at least partially covers the transparent area 116 of the test strip carrier 114. The test field 118 further comprises a test chemical 122 configured to conduct an optically detectable detection reaction. Test chemical 122 is further configured to at least partially absorb light having at least one absorption wavelength λ _abs 144, wherein at least one absorption wavelength λ _abs 144 is in the range 650 nm≤λ _abs ≤1100 nm . In addition, as illustrated in FIG. 4A, test field 118 includes at least one porous material 124 for at least partially filtering out solid components contained in sample 112. Test chemical 122 and at least partially porous material 124 may be arranged in separate layers, such as, for example, illustrated in FIG. 4A. In particular, as shown in FIG. 4B, test chemical 122 and at least partially porous material 124 may also be combined in a single layer. In addition, the test field 118 may include a spreading layer 148 configured to evenly distribute or spread the sample 112 of the physiological fluid over the surface, in particular, along the first side 140 of the test field 118, on which the sample 112 is applied.

The carrier film 120 further comprises at least one wavelength filter component 121 that is configured to substantially block light having a λ _block of λ _block ≦WL _lower , with 550 nm ≤ WL _lower ≤ 650 nm. In particular, the wavelength filter component 121 may, for example, be located within the carrier film 120, in particular, the wavelength filter component 121 may be dispersed within the carrier film 120, as illustrated in FIG. 4A. More specifically, the wavelength filter component 121 may be or include at least one long wavelength transmission filter 150. Additionally or alternatively, the wavelength filter component 121 may be or include at least one interference filter 152. In particular, the interference filter 152 may be located on at least one surface of the film 120 of the carrier element, in particular, as illustrated in Fig.4B, on the upper surface of the film 120 of the carrier element. However, the interference filter 152 can also be applied to the bottom surface of the carrier film 120, or to both the top and bottom surfaces of the carrier film 120.

In FIG. 5A is a plot of the transmission spectra of various embodiments of wavelength filter components 121. Specifically, by way of example, the first transmission spectrum 154 of the long wavelength transmission filter 150 and the second transmission spectrum 156 of the interference filter 152 can be illustrated. Specifically, as illustrated in FIG. 5A, the long wavelength pass filter may include a passband edge 158 rising with the wavelength of the light shown on the 160x axis. The y-axis 162 may specifically show the transmission of the wavelength filter components 121. In addition, the long-wavelength transmission filter 150 may have a characteristic wavelength 164 λ _dvp , while the T _dvp 166 transmission of the long-wavelength transmission filter 150 at λ _dvp 164 may be 50% of the maximum T _DSTmax 168 transmission of the long-wavelength transmission filter 150. Thus, in Fig. . 5, by way of example, T _{MDF max} 168 may be 80%, and therefore T _MDF 166 may be 0.5×80%=40%. In addition, the long-wavelength transmission filter 150 may have a slope S _dvp 170 of the rising edge 158 of the passband. In particular, as shown in equation (1) above, S _dvp can be calculated using the lengths of 172 waves λ _block and 174 waves λ _prop . In particular, at wavelength λ 172, the transmission _block T _dfp of the long-wavelength transmission filter 150 may be equal to or less than 5% T _dvpmax , and at wavelength 174 λ _prop T _dfp , the transmission of the long-wavelength transmission filter 150 may be equal to or greater than 95% T _dvpmax.

In addition, the interference filter 152 may have a characteristic wavelength λ 176 _{of the HPPF} , wherein, as illustrated by the second transmission spectrum 156 in FIG. 5, interference filter 152 may selectively block or attenuate all light having wavelengths below λ _HPF 176, while interference filter 152 may pass all light having wavelengths above λ _HPF 176.

As an example, the wavelength filter component 121 may specifically provide an estimate based on the intensity of the optical test strip 110, in particular the optically detectable response of the test chemical 122, for example, regardless of the ambient light and characteristics of the mobile device 130, in particular characteristics of the camera 132.

In FIG. 5B shows a plot of the reflectance spectra of a test chemical 122 for various concentrations of blood glucose, with the wavelength filter component 121 missing from the carrier film 120 of the test field 118. In particular, this graph may illustrate the reflectance spectra of various test fields containing the test chemical. 122 but not containing the wavelength filter component 121. For example, the illustrated reflectance values may occur 20 seconds after contact with the test chemical 122. In particular, different blood glucose concentrations may vary depending on the wavelength of the light shown on the x-axis 160, while the y-axis 132 may indicate the relative reflectance ability, in particular the percentage of reflectivity, for various concentrations of glucose in the blood. In particular, six different blood glucose concentrations can be illustrated by six different curves on a graph. In particular, curves 200 may illustrate the spectrum of a blood glucose concentration of 0 milligrams per deciliter (mg/dL), curves 202 may illustrate the spectrum of a blood glucose concentration of 40 mg/dL, curves 204 may illustrate a spectrum of a glucose concentration in blood at 80 mg/dl, curves 206 may illustrate the reflectance spectrum of a blood glucose concentration of 160 mg/dl, curves 208 may illustrate the reflectance spectrum of a blood glucose concentration of 260 mg/dl, and curves 210 may illustrate the reflectance spectrum of blood glucose concentration of 440 mg/dl.

In FIG. 5B shows a plot of the reflectance spectra of an embodiment of test field 118 for various blood glucose concentrations. In particular, the test field 118 includes a carrier element film 120 containing a wavelength filter component 121. Thus, the reflectance spectra shown in FIG. 5B can illustrate the reflectance spectra of the test chemical 122 for various concentrations of blood glucose, wherein light having a wavelength (172) λ _block can be substantially blocked by the length filter component 121 film 120 carrier test field 118. As an example, the reflectance spectra shown in FIG. 5B can illustrate the reflectance spectra of the same blood glucose concentrations used in FIG. 5B, with the reflection spectra superimposed on the first transmission spectrum 154 of the long wavelength transmission filter 150 as illustrated in FIG. 5A. For a better understanding, a portion of the transmission spectrum 154 of the long wavelength transmission filter 150 is further illustrated in FIG. 5V.

As illustrated, different blood glucose concentrations can be clearly separated and can have linear trajectories for wavelengths λ≥550 nm, in particular for λ≥600 nm. Thus, determining the analyte concentration, such as blood glucose concentration, of the sample 112 applied to the test field 118 of the optical test strip 110 according to the present invention can, in particular, improve the accuracy of the analyte concentration measurement. In particular, since, as illustrated, the determination of the analyte concentration can be difficult in a certain wavelength range, for example for wavelengths λ<550 nm, in which the analyte concentration, such as blood glucose concentration, changes significantly with very small changes in lighting conditions.

In FIG. 6A and 6B are graphs of red histograms recorded with an embodiment of a mobile device 130 containing a camera 132. As an example, in FIG. , when obtaining an image without using the wavelength filter 134 . In particular, for example, in the first histogram 178, the first illumination 180, in particular standard white light, eg 6500 K, and the second illumination 182, in particular greenish light, could be used for ambient illumination. As an example, it can be seen that under the second illumination 182, eg greenish light as an example, an error signal with about 10 samples can be recorded. However, in FIG. 6B, the red channel signal of camera 132 may be illustrated in a second histogram 184, eg similar to the first histogram shown in FIG. 6A, where a red filter may be used in the second histogram 184. For example, it can be seen that the second illumination 182, for example "greenish" illumination, in particular, can no longer give a false signal. As an example, the signal of the first illumination 180, such as white light, when comparing the first histogram 178 with the second histogram 184 may differ by about 100 samples, for example. This can occur, for example, due to filter losses. However, by way of example, the signal can be amplified and/or boosted, for example up to 180 samples, for example with stronger illumination.

In FIG. 7A shows a block diagram of an embodiment of a method for measuring the concentration of an analyte in a sample 112 of a physiological fluid applied to the test field 118 of an optical test strip 110 using a mobile device 130. The method includes the following steps:

i) (denoted by reference numeral 186) providing an optical test strip 110 comprising at least one wavelength filter component 121 that is configured to substantially block light having 146 wavelengths λ _block constituting λ _block ≤WL _lower , wherein 550nm≤WL _lower ≤650nm;

ii) (denoted by reference numeral 188) providing a mobile device 130, wherein the mobile device 130 comprises at least one camera 132 and at least one wavelength filter 134, the wavelength filter 134 being configured to substantially block light transmission, having wavelengths λ, constituting 1200 nm≥λ≥WL _vepx , and 800 nm ≤ WL _vepx ≤1000 nm;

iii) (denoted by reference numeral 190) applying the sample 112 of physiological fluid to the test field 118;

iv) (denoted by reference numeral 192) obtaining at least one image of the test field 118 containing the applied sample 112, using the camera 132 of the mobile device 130; And

v) (denoted by reference numeral 194) determining the concentration of an analyte in a sample 112 of a physiological fluid applied to a test field 118 by evaluating the optically detectable detection response of the test chemical 122 of the test field 118.

In FIG. 7B shows a flowchart of another embodiment of a method for measuring an analyte concentration in a physiological fluid sample 112 applied to a test field 118 of an optical test strip 110 using a mobile device 130. As shown in FIG. 7B, the method may further include step vi) (denoted by reference numeral 196) obtaining at least one image of the reference color field 126 using mobile device 130. For example, step vi) may be performed before step v). In particular, step iv) and/or step vi) may further include a substep 198 of illuminating the optical test strip 110, in particular with the illumination source 136 of the mobile device 130. List of reference symbols:

110 optical test strip

112 sample

114 test strip carrier

116 transparent area

118 test field

120 carrier film

121 wavelength filter components

122 test chemical

124 porous material

126 reference color field

128 set

130 mobile device

132 camera

134 wavelength filter

136 light source

138 processor

140 first side

142 second side

144 λ _absorb

146 λ _block

148 spreading layer

150 long wavelength pass filter

152 interference filter

154 first transmission spectrum

156 second transmission spectrum

158 edge of bandwidth

160 x axis

162 y axis

164 λ _fiber

166 T _fiberboard

168 T _DVPmax

170 S _fiberboard

172 λ _block

174 λ _prop

176 λ _HPF

178 first histogram

180 first lighting

182 second lighting

184 second histogram

186 step i)

188 step ii)

190 step iii)

192 step iv)

194 step v)

196 step vi

198 test strip illumination

200 curve 0 mg/dl

202 curve 40 mg/dl

204 curve 80 mg/dl

206 curve 160 mg/dl

208 curve 260 mg/dl

210 curve 440 mg/dl.

Claims (22)

1. Optical test strip (110) for measuring the concentration of an analyte in a blood sample (112), containing: a) a carrier element (114) of the test strip containing a transparent area (116); b) test field (118), while the test field (118): - contains at least one film (120) of the carrier element, while the film (120) of the carrier element is attached to the carrier element (114) of the test strip and covers the transparent area (116) of the carrier element (114) of the test strip; - contains at least one test chemical substance (122) deposited on the film (120) of the carrier element, wherein the test chemical substance (122) is configured to carry out an optically determined detection reaction with the analyte, while the test chemical substance (122) is additionally made with the possibility of partial absorption of light having at least one absorption wavelength (144) λ _abs in the range of 650 nm < λ _abs ≤ 1100 nm; And - contains at least one porous material (124) for at least partial filtering of the solid components contained in the sample (112); wherein the carrier element film (120) comprises at least one wavelength filter component (121) configured to substantially block light having wavelengths (146) λ _block of 10 nm ≤ λ _block ≤ WLlow, with 550 nm ≤ WL _lower ≤ 650 nm. 2. Optical test strip (110) according to claim 1, wherein the wavelength filter component (121) is located inside the carrier film (120). 3. Optical test strip (110) according to any one of the preceding claims, wherein the wavelength filter component (121) is selected from the group consisting of a long wavelength transmission filter component and a band pass filter component. 4. Optical test strip (110) according to any one of the preceding claims, wherein the wavelength filter component (121) comprises at least one long wavelength transmission filter (150), wherein the long wavelength transmission filter (150) comprises a pass band edge (158) , rising with the wavelength of light, while the long-wavelength transmission filter (150) additionally has a characteristic wavelength (164) of the wavelength λ _DWT , while the transmission of the long-wavelength transmission filter (150) by λ _DWT (164) is 50% of the maximum transmission of the long-wavelength transmission filter (150), and in this case WL _lower = λ _DWT (164). 5. Optical test strip (110) according to any one of paragraphs. 1, 3, 4, moreover, the wavelength filter component (121) contains an interference filter (152), while the interference filter (152) has a characteristic wavelength (176) λ _PFPF , while WL _lower = λ _PFPF (176), with this interference filter (152) is preferably located on at least one surface of the film (120) of the carrier element. 6. A method for measuring the concentration of an analyte in a blood sample (112) applied to the test field (118) of an optical test strip (110) using a mobile device (130), including: i) providing an optical test strip (110) according to any one of the preceding claims; ii) providing a mobile device (130), wherein the mobile device (130) comprises a camera (132) and a wavelength filter (134), wherein the wavelength filter (134) is configured to substantially block the transmission of light having wavelengths λ , constituting 1200 nm ≥ λ ≥ WL _top , and 800 nm ≤ WL _top ≤ 1000 nm; iii) applying a blood sample (112) to the test field (118); iv) obtaining an image of the test field (118) containing the sample (112) applied to it, using the camera (132) of the mobile device (130); And v) determining the concentration of the analyte in the blood sample (112) applied to the test field (118) by evaluating the optically detectable detection reaction of the test chemical (122) of the test field (118). 7. The method of claim 6, wherein the mobile device (130) further comprises at least one illumination source (136), wherein step iv) of the method further comprises illuminating the optical test strip (110). 8. The method according to claim 6 or 7, wherein the wavelength filter (134) comprises at least one short wavelength transmission filter, wherein the short wavelength transmission filter comprises a pass band edge incident with the wavelength of the light, wherein the short wavelength transmission filter further has a characteristic the wavelength λ _KVP , while the transmission of the short-wave transmission filter at λ _KVP is 50% of the maximum transmission of the short-wave transmission filter, and at the same time WL _top = λ _KVP . 9. The method according to any one of paragraphs. 6-8, with 800 nm ≤ WL _top ≤ 950 nm, in particular 800 nm ≤ WL _top ≤ 900 nm. 10. The method according to any one of paragraphs. 6-9, wherein the optical test strip (110) comprises the optical test strip (110) according to any one of the preceding claims relating to the optical test strip (110). 11. A set (128) for measuring the concentration of an analyte in a blood sample (112), and the set (128) contains an optical test strip (110) according to any one of paragraphs. 1-5 and further comprises a mobile device (130), wherein the mobile device (130) comprises a camera (132) and a wavelength filter (134), wherein the wavelength filter (134) is configured to substantially block the transmission of light having wavelengths λ of 1200 nm ≥ λ ≥ WL _top , with 800 nm ≤ WL _top ≤ 1000 nm.

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