Disclosed are an epitaxial wafer and a method of fabricating the same, and an electrochemical sensor, wherein the reference electrode comprises: a substrate (11); an InGaN layer (12) formed on a surface of the substrate (11) and having an In content between 20% and 60% so as to ensure that a transition from negatively charged surface states to positively charged surface states occurs within a composition range; and an InN layer (13) formed on a surface of the InGaN layer (12) facing away from the substrate (11) to act as a stabilization layer. The InGaN layer (12) with an In content between 20% and 60% allows generation of an electrochemical response independent of the concentration of a solution to be detected; and in addition, the InN layer (13) with a high density of intrinsic, positively charged surface states further improves the electrochemical stability of the reference electrode.

An ion detection device includes an ion sensor having a sensitive film immersed in an aqueous solution and outputting an output signal in accordance with a potential change of the sensitive film, and an adjuster acquiring the output signal of the ion sensor and adjusting a drive signal for driving the ion sensor to reduce an offset from a predetermined reference value in the output signal.

A sensor element comprising a first electrode containing Au as a main component, a second electrode and a solid electrolyte body. The first electrode and the second electrode are disposed to face each other while sandwiching the solid electrolyte body therebetween. The first electrode has a first electrode portion, which faces the second electrode while sandwiching the solid electrolyte body in cooperation with the second electrode, and a first lead portion. The solid electrolyte body has an uneven portion in a surface region facing the first electrode portion, the uneven portion having a plurality of protrusions. The first electrode portion is in direct contact with the uneven portion. An insulating layer whose surface has an uneven shape is formed on a surface of the solid electrolyte body facing the first lead portion. The first lead portion is in direct contact with the insulating layer.

A reference electrode assembly including an extension device having a first end opposite a second end and a fluid reservoir disposed between the first end and the second end, a reference electrode engageable with the extension device at the first end of the extension device, an end cap having an external electrical connector positioned at the second end of the extension device, a selectively actuatable spout fluidly coupled to the fluid reservoir, and a conductive wire extending through the fluid reservoir to electrically couple the reference electrode with the external electrical connector.

We provide an electrochemical sensor in which working microelectrodes are arranged in an array and interconnected in parallel. The working electrodes are arranged so that in use, they are electrochemically coupled to a counter electrode structure through an electrolyte. The sensor also includes a microporous body arranged so that in use, it is situated at a boundary between a gaseous environment and the electrolyte. In another aspect, we provide a method of sensing in which a sample of gas is admitted to a liquid electrolyte maintained by pores of a porous substrate. A voltage is applied to the liquid electrolyte, and an electrical response to the applied voltage is observed, thereby to detect electrochemical evidence of an analyte within the liquid electrolyte.

This disclosure relates to a biosensor, and methods of use thereof, for detecting a target in a sample comprising a photoelectrode comprising a conductive substrate and a photoactive material; a population of capture probes functionalized on the photoelectrode wherein the capture probes are capable of binding to the target and a reporter moiety; and the reporter moiety comprising a detectable label and a capture probe binding portion; wherein exposure of the target to the population of the capture probes results in binding of the target to a fraction of the population which results in a decrease in detection signal intensity compared to the intensity in the absence of the target, and subsequent binding of the reporter moiety to the remaining unbound capture probes results in an increase in detection signal intensity that is less than an increase from the reporter moiety binding to capture probes not exposed to the target.

An SO.sub.x sensor includes a lithium garnet electrolyte, a sensing electrode, a reference electrode, and a heating element. The sensing electrode includes Li.sub.2SO.sub.4 and at least one metal oxide or second metal sulfate. One surface of the sensing electrode is disposed on at least a portion of a surface of the lithium garnet electrolyte. A current collector is disposed on at least a portion another surface of the sensing electrode to electrically couple the sensing electrode to the reference electrode via a potentiometer. The reference electrode is disposed on the lithium garnet electrolyte. The heating element is capable of heating the sensing electrode and the lithium garnet electrolyte to a temperature sufficient to achieve a sensor response time of less than about 30 minutes.

A gas sensor includes a sensor element and a pump cell controller. The pump cell controller performs a normal time control process after a heater control process is started, the normal time control process including a main pump control process, an auxiliary pump control process of controlling an auxiliary pump cell so that a voltage for auxiliary pump reaches a target value, and a normal time measurement pump control process of pumping out oxygen in a measurement chamber by controlling the measurement pump cell so that a measurement voltage reaches a normal time target value. In an early stage of the normal time control process, the pump cell controller performs a correction process of correcting the target value of the voltage for auxiliary pump to a value higher than a target value in a period after the early stage.

A gas sensor includes a sensor element and a pump cell controller. During a normal operation time of the sensor element, the pump cell controller executes a normal time measurement pump control process of pumping out the oxygen in a measurement chamber by controlling a measurement pump cell so that voltage for measurement reaches a normal time target value. At the start-up time of the sensor element, the pump cell controller executes a start-up time measurement pump control process of pumping out the oxygen in the measurement chamber by controlling the measurement pump cell so that the voltage for measurement reaches a start-up time target value higher than the normal time target value. When determining that the oxygen concentration in the measurement chamber is stabilized, the pump cell controller makes switching from the start-up time measurement pump control process to the normal time measurement pump control process.

There is provided a chloride selective membrane including an epoxide-based matrix reacted with a stoichiometric amount of an amino compound and an activator such that the epoxide-based matrix comprises a number of quaternary ammonium groups.