US 12,292,407 B2
Measuring ion strength using closed-loop electrochemical ph modulation
Young Shik Shin, Mountain View, CA (US); Nadezda Fomina, Redwood City, CA (US); Christopher Johnson, San Carlos, CA (US); Armin Darvish, Brisbane, CA (US); and Christoph Lang, Sunnyvale, CA (US)
Assigned to Robert Bosch GmbH, Stuttgart (DE)
Filed by Robert Bosch GmbH, Stuttgart (DE)
Filed on Feb. 24, 2021, as Appl. No. 17/184,274.
Prior Publication US 2022/0268729 A1, Aug. 25, 2022
Int. Cl. G01N 27/416 (2006.01); C12Q 1/6851 (2018.01); G05D 21/02 (2006.01)
CPC G01N 27/4167 (2013.01) [C12Q 1/6851 (2013.01); G05D 21/02 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for monitoring a chemical reaction, comprising
(a) starting the chemical reaction in a buffered solution equipped with a closed-loop device, wherein
the buffered solution comprises a pH modulating agent;
the closed-loop device comprises an electronic controller, a working electrode, a counter electrode, a reference electrode, and a sensing element, wherein the working electrode, the counter electrode, the reference electrode, and the sensing element are immersed in the buffered solution, and wherein the sensing element is positioned on top of the working electrode with an insulation layer therebetween to provide physical separation; and
the chemical reaction causes a change of ionic strength of the buffered solution;
(b) applying a current or voltage to the working electrode, whereupon the pH modulating agent causes a continuous cycling of pH modulation between at least two target pH values in a zone adjacent to a surface of the working electrode and the sensing element;
(c) detecting the change of ionic strength of the buffered solution with the closed-loop device, wherein the detecting comprises:
(c1) controlling the current or voltage applied to the working electrode, thereby modulating the pH value in the zone between the at least two target pH values;
(c2) analyzing the current or voltage applied to the working electrode and a signal output from the sensing element; and
(c3) quantitating the change of ionic strength of the buffered solution from the current or voltage applied to the working electrode and the signal output from the sensing element; and
(d) repeating steps (b) and (c) at least one time.