GLUCOSE SENSOR

A method for determining the glucose value in blood or in interstitial liquids and to a glucose sensor including a catheter which has one or more openings in the region of the distal end of the catheter; a first optical waveguide which is arranged in the catheter and which includes a coupling surface at the distal end of the optical waveguide; a measuring probe which is arranged in the region of the distal end of the catheter, is coupled to the coupling surface of the first optical waveguide, and has a mirror arranged opposite the coupling surface of the first optical waveguide and a detection chamber between the coupling surface of the first optical waveguide and the mirror; a detection liquid for glucose in the detection chamber; and a membrane which encloses at least the detection chamber filled with the detection liquid and which has a separation capacity of maximally 20 kDA.