Method and apparatus for analyte measurement including material status analysis

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure
• is determined,
• wherein said material is human tissue and said analyte is glucose present in an interstitial fluid thereof, and
• wherein at least one main frequency of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure comprise a first main modulation frequency and a second main modulation frequency, wherein said first main modulation frequency is chosen sufficiently low such that the response signal reflects at least in part absorption of excitation radiation within the interstitial fluid, wherein the second main modulation frequency is higher than the first main modulation frequency, and wherein in said analysis, response signals corresponding to said first and second main modulation frequencies, or quantities derived therefrom, are mathematically combined to yield information indicative of the absorption in the interstitial fluid,
• wherein the first main modulation frequency f is chosen in a range of
• 4
• ·
• f
• min
• >
• f
• >
• f
• min
• ,
• wherein fmin is defined as fmin=kt·α(λ)2/(2·p·Cp),
• wherein kt, ρ, and Cp are a thermal conductivity, a density and a specific heat capacity of the tissue, respectively, and α(λ) is an absorption coefficient for excitation radiation having wavelength λ in said tissue.

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment
• and wherein, based on a result of said material status analyzing procedure, at least one of
• selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure
• is determined,
• wherein said material is human skin, said analyte is glucose present in an interstitial fluid thereof, and said material status comprises a water content of the human skin,
• wherein in case a higher water content is determined in said material analyzing procedure, shorter wavelengths among a set of predetermined analyte-characteristic-wavelengths are preferentially used in the analyte measurement procedure.

A method of analyzing a material comprising at least one analyte said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• a selection of analyte-characteristic-wavelengths used during said analyte measurement procedure or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure
• is determined,
• wherein said material is human skin, said analyte is glucose present in an interstitial fluid thereof, and said material status comprises a water content of the human skin,
• wherein at least one of the one or more main frequencies of the modulation of said excitation radiation intensity used during said analyte measurement procedure is/are adapted to the water content determined in said material analyzing procedure in such a way that with all other characteristics of the material status the same, higher main frequencies of the modulation are chosen for higher water contents.

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure is determined,
• wherein said material is human tissue, said analyte is glucose present in an interstitial fluid thereof, and said material status comprises a thickness of a stratum corneum overlying the interstitial fluid, wherein said thickness of the stratum corneum is directly or indirectly assessed based on response signals established for identical wavelengths of the excitation radiation but for different intensity modulation frequencies of said excitation radiation, wherein said wavelength is chosen to match an absorption band of a substance present with different concentrations in the stratum corneum and the interstitial fluid, respectively.

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• a selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure is determined,
• wherein said material is human tissue, said analyte is glucose p resent in an interstitial fluid thereof, and said material status comprises a thickness of a stratum corneum overlying the interstitial fluid,
• wherein at least one of the one or more main frequencies of the modulation of said excitation radiation intensity used during said analyte measurement procedure is/are adapted to the thickness of the stratum corneum overlying the interstitial fluid determined in said material analyzing procedure in such a way that with all other characteristics of the material status the same, a lower main frequency of the modulation is chosen for higher stratum corneum thicknesses.

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the t body, or of a component included therein, to beat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• a selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure
• is determined,
• wherein said material is human skin, said analyte is glucose present in an interstitial fluid thereof, and said material status comprises the pH value of the human skin.

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure
• is determined,
• wherein said material is human tissue and said analyte is glucose present in an interstitial fluid thereof,
• wherein the tissue is skin at a fingertip of a human subject, and wherein the material status comprises the average height of the epidermal ridges, wherein said average height of the epidermal ridges is estimated using said additional sensor equipment formed by a dedicated fingerprint sensor.

A method of analyzing a material comprising at least one analyte, said method comprising

• an analyte measurement procedure, in which
• the material is brought in thermal contact or pressure transmitting contact with a measurement body, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• excitation radiation is irradiated into the material to be absorbed therein wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• a physical response of the measurement body, or of a component included therein, to heat or pressure waves received from said material upon absorption of said excitation radiation is detected using a detection device which generates response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation,
• wherein the method further comprises an analyzing step, in which said analyzing is carried out based, at least in part, on said response signal,
• wherein the method further comprises a material status analyzing procedure, in which a present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein, based on a result of said material status analyzing procedure, at least one of
• a selection of analyte-characteristic-wavelengths used during said analyte measurement procedure or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure
• is determined,
• wherein said measurement body or a component in said measurement body has electrical properties that change in response to a local change in temperature or a change in pressure associated therewith, and wherein said detection device comprises electrodes for capturing electrical signals representing said electrical properties.

An apparatus for analyzing a material comprising at least one analyte, said apparatus comprising

• a measurement body having a contact surface suitable to be brought in thermal contact or pressure transmitting contact with said material, said thermal or pressure transmitting contact permitting heat or pressure waves generated by absorption of excitation radiation in the material to be transferred to said measurement body,
• an excitation radiation source configured for irradiating excitation radiation into the material to be absorbed therein,
• a detection device for detecting a physical response of the measurement body, or of a component included therein, to heat or a pressure wave received from said material upon absorption of said excitation radiation and for generating a response signal based on said detected physical response, said response signal being indicative of a degree of absorption of excitation radiation, and
• a control system,
• wherein said control system is configured to
• control the excitation radiation source to irradiate excitation radiation into the material to be absorbed therein, wherein the intensity of said excitation radiation is time-modulated, and wherein said excitation radiation comprises radiation of different analyte-characteristic-wavelengths that are irradiated one or both of simultaneously and sequentially, and
• to control the detection device to detect said physical response and to generate response signals indicative of the degree of absorption of said excitation radiation,
• wherein the control system is further configured to carry out a material status analyzing procedure, in which the present status of the material is analyzed based on one or more of
• one or more response signals established when the material is irradiated with excitation radiation at a wavelength different from said analyte-characteristic-wavelengths,
• one or more response signals established for excitation radiation with the same analyte-characteristic-wavelengths as used in the analyte measurement step, but for at least partially different intensity modulation frequencies of said excitation radiation than in the analyte measurement step, and
• one or more measurements related to a material status carried out with additional sensor equipment,
• and wherein the control system is configured for determining, based on a result of said material status analyzing procedure, at least one of
• selection of analyte-characteristic-wavelengths used during said analyte measurement procedure, or relied on during said analysis,
• an absolute time or a relative time proportion of use of analyte-characteristic-wavelengths during said analyte measurement procedure, an individual excitation radiation intensity, or a relative weight given to the wavelengths in the analysis,
• a selection of analyte-characteristic-wavelengths to be used simultaneously during said analyte measurement procedure, and
• a selection of one or more main frequencies of the modulation of said excitation radiation intensity to be used during said analyte measurement procedure,
• wherein said measurement body or a component in said measurement body has electrical properties that change in response to a local change in temperature or a change in pressure associated therewith, and wherein said detection device comprises electrodes for capturing electrical signals representing said electrical properties.