A test device for testing an oxidation potential of an electrolyte is provided. The test device comprises a cavity, a test unit, a detector, a processing unit, and a display. The test unit comprises a positive plate comprising a first through hole, a negative plate comprising a second through hole, a first infrared window covering the first through hole, a second infrared window covering the second through hole, and an electrolyte located between the positive electrode plate and the negative electrode plate. The first through hole and the second through hole penetrate each other. The first infrared window, the positive plate, the negative plate, and the second infrared window are stacked with each other. An infrared light beam passes through the first infrared window, the first through hole, the electrolyte, the second through hole, and the second infrared window in sequence and then is detected by the detector;

A method for determining a concentration of an analyte in a fluidic sample is described. A sample is applied to a biosensor including an electrochemical cell having electrodes. A predetermined voltage waveform is applied during at least first and second time intervals. At least first and second current values are measured during the first and second time intervals, respectively. A turning point time is determined during the first time interval at which the measured first current values transition from a first to a second profile. The concentration of analyte in the sample is calculated based on determined turning point time and at least one measured current value. In another example, a physical characteristic of the sample is estimated based on measured current values. The concentration is calculated using a first or second model if the estimated physical characteristic of the sample is in a first or second range, respectively.

A gel for use in a pH or an ORP sensor, components of the gel comprising water, a reference electrolyte salt, a buffering system for adjusting pH of the gel, and a polymeric gelling agent, and the gel does not degrade under gamma irradiation.

This disclosure relates to a glucose-sensing electrode including a nanoporous metal layer and an electrolyte ion-blocking layer formed over the nanoporous metal layer. The nanoporous metal layer is capable of oxidizing both glucose and maltose without an enzyme specific to glucose in the glucose-sensing electrode. The electrolyte ion-blocking layer is configured to inhibit Na.sup.+, K.sup.+, Ca.sup.2+, Cl.sup.−, PO.sub.4.sup.3− and CO.sub.3.sup.2− from diffusing toward the nanoporous metal layer such that there is a substantial discontinuity of a combined concentration of Na.sup.+, K.sup.+, Ca.sup.2+, Cl.sup.−, PO.sub.4.sup.3− and CO.sub.3.sup.2− between over and below the electrolyte ion-blocking layer.

A method of determining a disinfectant composition of a municipal water supply from a water sample that includes: (a) obtaining a water sample from a water source at a sampling location; (b) adding a chlorine-containing material to the water sample in the presence of an oxidation reduction potential (ORP) measurement device; (c) generating a plurality of ORP measurements during addition of the chlorine-containing material to the water sample; (d) estimating a concentration of one or more of free ammonia, fully combined ammonia, monochloramine, or a mixture of dichloramine and trichloramine in the water sample in which the estimation is derived from the relationship between the added chlorine material and the plurality of ORP measurements; and (e) determining a disinfectant composition of the water source at the water sampling location from the concentration calculation. A method of determining free ammonia composition is also included.

The invention refers to a device and a method of quantification of analytes concentration, making use of a device that comprises an electrochemical cell (1) which contains the analyte, a load (2) which is connected in parallel to the electrochemical cell (1), and a readout unit (3), which is connected in parallel with the load (2). This includes the stages of quantification of the concentration of analytes, the charge transfer from the electrochemical cell (1) to the load (2), the determination of the voltage across the load (2) and the determination of the analyte concentration from the correlation between the analyte concentration and the voltage across the load (2).

A method of exposing a sample to an electrical effect for electrochemical analysis of the sample in an electrolyte solution is disclosed. The method comprises causing an external electrical conductor of an electrode head to apply the electrical effect, the external electrical conductor of the electrode head being external to the electrode head and on an external side of the sample exposed to the electrolyte solution. Apparatuses are also disclosed.

A method for determining a concentration of an analyte in a fluidic sample is described. A sample is applied to a biosensor including an electrochemical cell having electrodes. A predetermined voltage waveform is applied during at least first and second time intervals. At least first and second current values are measured during the first and second time intervals, respectively. A turning point time is determined during the first time interval at which the measured first current values transition from a first to a second profile. The concentration of analyte in the sample is calculated based on determined turning point time and at least one measured current value. In another example, a physical characteristic of the sample is estimated based on measured current values. The concentration is calculated using a first or second model if the estimated physical characteristic of the sample is in a first or second range, respectively.

A dialysis method and system for determining an amount of total chlorine in a partially purified water sample is disclosed. The system includes a water machine that produces at least partially purified water including an at least partially purified water sample and a dialysis machine that provides a dialysis treatment to a patient. The dialysis machine receives the at least partially purified water from the water machine to prepare dialysis fluid for the dialysis treatment. The system also includes a total chlorine detector configured to receive the at least partially purified water sample, at a first time apply a source voltage to the at least partially purified water sample, and at a second time stop applying the source voltage to the at least partially purified water sample and instead monitor a sensed electrical parameter to determine an amount of total chlorine in the at least partially purified water sample.

Various methods, devices, and systems for determining the concentration of microorganisms in a sample and determining the susceptibility of such microorganisms to one or more antibiotics or other types of anti-infectives are disclosed herein. More specifically, methods for quantifying microorganisms based on redox reactions are disclosed along with systems and devices for quantifying such microorganisms using certain oxidation reduction potential (ORP) sensors. Moreover, methods for determining the susceptibility and the degree of susceptibility of microorganisms to one or more anti-infectives are disclosed along with multiplex systems for such assays.