PROCESS AND DEVICE FOR DETERMINING AN ANALYTE IN A BIOLOGICAL SAMPLE

摘要

A process for determining the concentration of an analyte in a biological sample in which light is irradiated in a detection step into the sample by means of radiation devices through a surface bounding the biological sample as primary light and light emitted from the biological sample by a surface bounding it is detected at a predetermined measuring distance as secondary light in order to determine a variable physical property of the light owing to the interaction with the biological sample which is measurable as a measurement which is correlated with the concentration of the component in the biological sample, and the concentration of the component is found in an evaluation step on the basis of the measurement made in the detection step. In order to obtain good accuracy of measurement without a reagent and non-invasively, it is proposed that, in the detection step: (a) frequency domain spectroscopic measurements be made with at least two different measurement light paths between the irradiation and measurement points without moving the light irradiation device; (b) each of the frequency domain spectroscopic measurements be made at at least two different light wavelengths; and (c) the phase shift in the secondary light in relation to the primary light and an intensity value be determined in the frequency domain spectroscopic measurements.