Provided is a potential measurement device including: a first substrate having read electrodes arranged in a two-dimensional array; and a second substrate on which the first substrate is stacked, in which each of the read electrodes includes at least one or more AD conversion circuits each having independent correspondence to the read electrode, and at least a part of the AD conversion circuits is arranged in a two-dimensional array on the second substrate.

A reference electrode system for a pH-sensor system includes: a first junction having a membrane with a sealed side; a reference electrode, the reference electrode and/or an electrically conducting wire of the reference electrode being covered completely except for an end portion of the reference electrode, by a sleeve; and a tube that is arranged, at least partly, around the reference electrode, the electrically conducting wire, and the sleeve, the tube having a closed end which is arranged near the end portion of the reference electrode.

An online calibration system for an electrochemical sensor. The calibration system comprises a calibration electrode coupled with a redox species, where the redox species is configured to control a pH of a reference solution local to the calibration electrode, such that when a voltammetric signal is applied to the calibration electrode the output generated from the calibration system is determined by the local environment pH. The output signal from the calibration system is used to calibrate a reference potential generated by a reference system of the electrochemical sensor to correct for drift in the reference potential when the electrochemical sensor is being used. The calibration electrode may be disposed in a reference cell of the electrochemical sensor.

A reference electrode of an electrochemical sensor includes a substrate having a well, a channel, and a conductive element. The well extends from a first surface of a substrate towards a second surface of the substrate. The channel is within the substrate. A longitudinal axis of the channel may be substantially perpendicular to a longitudinal axis of the well. The channel has a first end connected to the well and a second end that is in contact with the conductive element. The channel and the wells form a flow path of a conductive medium. The flow path may be coupled to a manipulating element such as an agitating element or heating element that promotes flow of the membrane.

A reference electrode of an electrochemical sensor includes a substrate having well, a channel, and a conductive element therein. The well extends from a first surface of a substrate towards a second surface of the substrate. The channel is within the substrate. A longitudinal axis of the channel may be substantially perpendicular to a longitudinal axis of the well. The channel has a first end connected to the well and the conductive element is exposed to a second of the channel. The channel and the wells form a flow path of a conductive medium. A valve is coupled to the flow path and configured to control a flow of the conductive medium to the electrically conductive element through the flow path.

A reference electrode of an electrochemical sensor includes a substrate having internal walls defining a well and a channel. The reference electrode includes a conductive element disposed in the substrate. The well extends from a first surface of a substrate towards a second surface of the substrate. The channel is within the substrate. The channel has a first end connected to the well and a second end that is in contact with the conductive element. The reference electrode may include an additional well that extends from the first surface towards the second surface. The additional well may be connected to the second end of the channel and may be in contact with the conductive element. The channel and the wells form a flow path of a conductive medium. The flow path may be coupled to an agitating element or heating element that promotes flow of the conductive medium.

Disclosed herein is a reference half-cell including a tube including an electron interface made of polypropylene graphite, an electrolyte solution, a metal electrode, and a seal. Alternatively, the reference half-cell may be employed without an electrolyte solution and a seal. The electron interface along the first end of the tube may be either an integrated part of the tube or a component separate from and affixed at its ends to the tube to maintain the electron interface in a stationary position relative to the tube. The use of electrically conductive polypropylene for the electron interface provides a half-cell that has good electrically conductivity and high moisture inhibitiveness and, as a result, has an improved service life.

An electrochemical sensor may include a common reference electrode, at least one counter electrode, and a work electrode platform including a work electrode and at least one diffusion control layer. The work electrode may be electrically coupled to the common reference electrode. The electrode may include a reagent substrate configured to react with an analyte to produce a signal indicative of a concentration of the analyte. The at least one diffusion control layer may be configured to control the diffusion of the analyte to the work electrode.

A single-use disposable potentiometric reference sensor includes an insulating base substrate, a reference electrode disposed on the insulating base substrate where the reference electrode is a silver-silver chloride electrode, an internal layer disposed on the reference electrode where the internal layer is an amorphous salt layer that includes an amorphous polysaccharide and a salt having equi-mobility cations and anions, and a semipermeable cover membrane disposed over the internal layer where the semipermeable cover membrane has water vapor and ion permeability.

Closed-loop systems and methods for controlling pH. The system includes a working electrode, a counter electrode, a reference electrode, a first ion-sensitive field-effect transistor (ISFET), a second ISFET, and an electronic controller. The working electrode, the counter electrode, the reference electrode, and a first sensing terminal of the first ISFET are immersible in an active solution. A second sensing terminal of the second ISFET is immersible in a reference solution. The electronic controller is configured to apply a first amount of current or voltage to the working electrode and determine a differential voltage between the first ISFET and the second ISFET. The electronic controller is also configured to set a second amount of current or voltage to reduce a difference between the differential voltage and a target voltage. The electronic controller is further configured to apply the second amount of current or voltage to the working electrode.