US 11,903,708 B2
Switchable low voltage electrochemical sensing for interfering species rejection
Samson Chen, Pasadena, CA (US); Axel Scherer, Barnard, VT (US); Muhammad Musab Jilani, Pasadena, CA (US); and Xiomara L. Madero, Pasadena, CA (US)
Assigned to CALIFORNIA INSTITUTE OF TECHNOLOGY, Pasadena, CA (US)
Filed by CALIFORNIA INSTITUTE OF TECHNOLOGY, Pasadena, CA (US)
Filed on Sep. 27, 2018, as Appl. No. 16/144,174.
Claims priority of provisional application 62/564,921, filed on Sep. 28, 2017.
Prior Publication US 2019/0090797 A1, Mar. 28, 2019
Int. Cl. A61B 5/1486 (2006.01); A61B 5/1459 (2006.01); G01N 27/419 (2006.01); G01N 27/30 (2006.01); A61B 5/145 (2006.01)
CPC A61B 5/14865 (2013.01) [A61B 5/1459 (2013.01); A61B 5/14532 (2013.01); G01N 27/30 (2013.01); G01N 27/419 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method comprising:
providing a sensor to detect a molecule of interest, the sensor comprising:
a substrate;
a working electrode on the substrate;
a reference electrode on the substrate;
a counter electrode on the substrate; and
an enzyme layer covering the working electrode, and implanting the sensor in biological tissue;
applying a plurality of voltages to the working electrode;
measuring a plurality of currents at the working electrode, each current of the plurality of currents corresponding to a voltage of the plurality of voltages, the plurality of currents comprising a first current and a second current, the first current being higher than the second current;
generating a measurement curve of the plurality of currents plotted against the plurality of voltages;
comparing the measurement curve to a reference curve, the reference curve corresponding to a measurement of the molecule of interest without interfering species, the reference curve consisting of a graph of positive currents versus positive voltages; and,
if the measurement curve corresponds to the reference curve:
selecting the first current of the plurality of currents corresponding to a first voltage; and
calculating a concentration of the molecule of interest based on the first current but not the second current;
if the measurement curve does not correspond to the reference curve:
selecting the second current of the plurality of currents corresponding to a second voltage, the second voltage being lower than the first voltage; and
calculating a concentration of the molecule of interest based on the second current but not the first current.