US 12,186,076 B2
Optical based glucose sensor
David L. Probst, Chandler, AZ (US); and Mark R. Boone, Gilbert, AZ (US)
Assigned to Medtronic, Inc., Minneapolis, MN (US)
Filed by Medtronic, Inc., Minneapolis, MN (US)
Filed on Feb. 9, 2021, as Appl. No. 17/171,474.
Prior Publication US 2022/0248986 A1, Aug. 11, 2022
Int. Cl. A61B 5/1455 (2006.01); A61B 5/145 (2006.01); A61B 5/1459 (2006.01); A61B 5/1486 (2006.01); A61K 49/00 (2006.01); A61B 5/00 (2006.01)
CPC A61B 5/14532 (2013.01) [A61B 5/1455 (2013.01); A61B 5/1459 (2013.01); A61B 5/14865 (2013.01); A61K 49/0036 (2013.01); A61B 5/686 (2013.01)] 26 Claims
OG exemplary drawing
 
1. A medical device comprising:
an optical sensor comprising:
a light source configured to emit radiation;
a reference optical beacon comprising a first fluorophore configured to absorb at least a portion of the radiation emitted by the light source and emit, based on a first concentration of oxygen in a fluid proximate the reference optical beacon, a first fluorescence;
a test optical beacon comprising:
a reagent substrate configured to react with glucose proximate the reagent substrate to modulate a concentration of oxygen in the fluid, wherein the reagent substrate comprises:
glucose oxidase, wherein the glucose oxidase is configured to oxidize the glucose to yield hydrogen peroxide; and
catalase, wherein the catalase is configured to produce oxygen by reducing the hydrogen peroxide that the glucose oxidase yields into water and oxygen,
wherein the reagent substrate is configured to modulate the concentration of oxygen in the fluid by consumption of oxygen by the glucose oxidase to oxidize the glucose and by production of oxygen by the catalase from the hydrogen peroxide that the glucose oxidase yields to generate a modulated concentration of oxygen in the fluid proximate a second fluorophore; and
the second fluorophore configured to absorb at least a portion of the radiation emitted by the light source and emit, based on the modulated concentration of oxygen proximate the second fluorophore, a second fluorescence; and
a photodetector configured to detect the first fluorescence and the second fluorescence; and
processing circuitry operatively coupled to the optical sensor, wherein the processing circuitry is configured to:
receive, from the optical sensor, one or more signals indicative of the first fluorescence and the second fluorescence; and
determine, based on the one or more signals, a difference between the first fluorescence and the second fluorescence, wherein the difference is indicative of a concentration of the glucose.