Wide band field response measurement for glucose determination

摘要

A method and device for determining the glucose level in living tissue are based on measuring the response of the tissue an electric field as well as temperature measurements. In order to improve accuracy, it has been found that measurements in at least three frequency ranges between 1 kHz and 200 kHz, 0.2 MHz an 100 MHz as well as above 1 GHz should be combined since the response of the tissue in these different frequency ranges is ruled by differing mechanisms.

主权项

1. A device for measuring a glucose level in living tissue, said device comprising
an electrode arrangement to be applied against said tissue, a signal generation circuit, wherein said signal generation circuit is connected to said electrode arrangement in order to generate an AC signal voltage in said electrode arrangement, a measuring circuit for measuring a response of said tissue to a field generated by said electrode arrangement due to said signal voltage, a first temperature sensor generating a first temperature signal indicative of a temperature of said tissue, a control unit for operating said signal generation circuit, wherein said control unit is structured and adapted to operate said signal generation circuit and said measuring circuit at least at a first frequency for measuring a first electric parameter, at a second frequency for measuring a second electric parameter and at a third frequency for measuring a third electric parameter, wherein said first frequency is in a first frequency range between 1 kHz and 200 kHz, said second frequency is in a second frequency range between 0.2 MHz and 100 MHz, and said third frequency is in a third frequency range of at least 1 GHz, wherein said control unit is further structured and adapted to derive said glucose level from a combination of at least said first, second and third electric parameter and said first temperature parameter, and wherein said control unit is structured and adapted to determine said glucose level from all of the following parameters p1-p7: p1—a value depending on the phases of the impedances measured at several frequencies in the second frequency range at frequencies larger than 30 MHz, measured by means of an electrode pair having a separation gap of at least 2 mm, p2—a value depending on the phases of the impedances measured at several frequencies in the second frequency range at frequencies larger than 30 MHz, measured by means of an electrode pair having a separation gap of less than 2 mm, p3—a value depending on the phases of the impedances measured at several frequencies in the second frequency range at frequencies larger than 100 kHz, p4—a value depending on the magnitudes of the impedances measured at several frequencies in the second frequency range at frequencies larger than 100 kHz, p5—a value depending on the phases of the transmission coefficient measured at at least one frequency in the third frequency range, measured by means of an electrode pair having a separation gap of at least 1 mm, p6—a value depending on the phases of the transmission coefficient measured at at least one frequency in the third frequency range, measured by means of an electrode pair having a separation gap of less than 1 mm, and p7—a value depending on the temperature.