PCT No. PCT/DE94/01290 Sec. 371 Date Feb. 9, 1996 Sec. 102(e) Date Feb. 9, 1996 PCT Filed Oct. 29, 1994 PCT Pub. No. WO95/12348 PCT Pub. Date May 11, 1995Method and apparatus for the analytical determination of glucose concentration in a biological matrix, wherein in a detection step light from a light emitter is irradiated into the biological matrix as primary light via a boundary surface of the biological matrix and light emerging from the the biological matrix through a boundary surface is being detected by a light detector in order to determine a measurable physical light property which is changed by interaction with the biological matrix and which correlates with the glucose concentration of said matrix. The glucose concentration is ascertained in an evaluation step on the basis of said change of the physical light property determined in at least one detection step in comparison with a calibration. In order to achieve by such a method good analytical accuracy in reagent-free and non-invasive manner, for instance to observe the change of the concentration of the analyzed substance (monitoring) over an adequate time interval, a measurable parameter corresponding to the light transit-time within the biological matrix between a defined irradiation site and a defined detection site and correlating with the glucose concentration is determined in the detection step.
Method and apparatus for the analysis of glucose in a biological matrix