An embodiment provides a method for determining the alkalinity of an aqueous sample using an alkalinity sensor, including: monitoring the pH of an aqueous sample using a pH sensor in a sample cell, the pH sensor including a pH sensor electrode made of boron-doped diamond; generating hydronium ions, using a hydronium generator, in the aqueous sample in the sample cell, the hydronium generator including a hydronium-generating electrode; changing the pH of the aqueous sample by causing the hydronium generator to generate an amount of hydronium ions in the aqueous sample; quantifying and converting a current or charge to the number of hydronium ions produced to an end point of the electrochemical titration, the end point correlating to the alkalinity of a sample; and analyzing the alkalinity of the aqueous sample based on the generated amount of hydronium ions and the resulting change in pH monitored by the pH sensor.

The invention provides novel microfluidic coulometric sensors having a silver (Ag) band electrode longitudinally placed in a microchannel affording visual readout suitable for the naked eye, and methods of fabrication and applications thereof.

A plating apparatus capable of preventing difference in an electrode potential between the pair of cathodes and a disturbance in a current distribution in Haring cell test and so on is provided. A plating apparatus (1) has an anode (12) and a pair of cathodes (13X) (13Y) which are provided in a plating bathtub (11); a plating power source (14) to supply an electric current between the anode (12) and the pair of cathodes (13X) (13Y); and a feedback circuit (21) to have an electrode potential of a first cathode (13X) equal to an electrode potential of a second cathode (13Y) while a summation of electric currents flowing through the pair of cathodes (13X) (13Y) is kept constant.

An automated total organic carbon analyzer is described. Embodiments of the system include two features, namely the development of a selective oxidation reactor to oxidize organic contaminants to their corresponding organic acids, and the measurement of the organic acids individually by chain length using an electroanalytical detector. Combining this electroanalytical approach with sequential detection capabilities (such as spectrophotometry) can expand the instrument capabilities by providing organic contaminant speciation. The described reactor performs selective oxidation of organic carbon to organic acids followed by complexation with a proprietary ligand, then selective detection using electroanalytical accumulation and desorption of organic acids performed at an electrode surface.

A fluid sensing system includes a microfluidic chip, multiple sensors, and a communication device. The microfluidic chip includes at least one microfluidic channel extending a length through the microfluidic chip. The microfluidic chip is fluidly connected to a process fluid such that a fluid sample from the process fluid flows through the at least one microfluidic channel. The multiple sensors are operatively connected to the at least one microfluidic channel of the microfluidic chip. The multiple sensors are configured to monitor multiple different properties of the fluid sample within the at least one microfluidic channel. The communication device is operatively connected to the multiple sensors. The communication device is configured to receive data parameters representative of the multiple different properties of the fluid sample from the multiple sensors and wirelessly transmit the data parameters to a remote location.

A fluid sensing system includes a microfluidic chip, multiple sensors, and a communication device. The microfluidic chip includes at least one microfluidic channel extending a length through the microfluidic chip. The microfluidic chip is fluidly connected to a process fluid such that a fluid sample from the process fluid flows through the at least one microfluidic channel. The multiple sensors are operatively connected to the at least one microfluidic channel of the microfluidic chip. The multiple sensors are configured to monitor multiple different properties of the fluid sample within the at least one microfluidic channel. The communication device is operatively connected to the multiple sensors. The communication device is configured to receive data parameters representative of the multiple different properties of the fluid sample from the multiple sensors and wirelessly transmit the data parameters to a remote location.

A method of electrochemical sensing includes providing an electrochemical sensor comprising a glassy carbon substrate and gold nanoparticles located on a surface of the glassy carbon substrate; and sensing electrochemically a compound selected from the group consisting of polyfluoroalkyl compounds or perfluoroalkyl compounds using the electrochemical sensor. PFOA quantification was performed by Square Wave Adsorptive Cathodic Stripping Voltammetry (SW-AdCSV) in test solutions with a 100-5,000 ppt concentration. The concentration has a linear relationship with the stripping current within this range. Analysis of tap and groundwater samples performed by additions method demonstrated precision and accuracy above 95%. These electrodes show stability throughout 200 cycles, and reproducibility across similarly prepared but different electrodes above 97.5%. Providing the electrochemical sensor can include providing at least one member selected from the group consisting of perfluoro-1-octanethiol (PFTO), 2,2,2-trifluoroethanethiol (TFET) or perfluorodecanethiol (PFDT) on the surface of the glassy carbon substrate.

A method of electrochemical sensing includes providing an electrochemical sensor comprising a glassy carbon substrate and gold nanoparticles located on a surface of the glassy carbon substrate; and sensing electrochemically a compound selected from the group consisting of polyfluoroalkyl compounds or perfluoroalkyl compounds using the electrochemical sensor. PFOA quantification was performed by Square Wave Adsorptive Cathodic Stripping Voltammetry (SW-AdCSV) in test solutions with a 100-5,000 ppt concentration. The concentration has a linear relationship with the stripping current within this range. Analysis of tap and groundwater samples performed by additions method demonstrated precision and accuracy above 95%. These electrodes show stability throughout 200 cycles, and reproducibility across similarly prepared but different electrodes above 97.5%. Providing the electrochemical sensor can include providing at least one member selected from the group consisting of perfluoro-1-octanethiol (PFTO), 2,2,2-trifluoroethanethiol (TFET) or perfluorodecanethiol (PFDT) on the surface of the glassy carbon substrate.

Disclosed are methods of measuring moisture. Specifically, methods of measuring moisture on dry or nearly dry surfaces using an electrochemical sensor are disclosed. The method comprises applying a coating comprising an electrolyte to an electrode wherein water in the air can permeate the coating, applying a voltage to the electrode, detecting a current and, determining if the current indicates the presence of moisture. As a voltage is applied, oxygen in the water is reduced and produces a measurable signal. The method includes measuring the amount of or decrease of dissolved oxygen (in water) at the surface of the electrode over time. Reduction of oxygen acts as a surrogate for water/moisture and, as such, the dryness of the surface of the electrode is calculated based on a predetermined relationship between current and dissolved oxygen (in water). The method is also adapted to measure other target chemicals in a coating.

A single electron transistor conjugated to a bacteriophage form a detectable probe where an RF signal identify the location of such probe at the site of specific biological matrix and provide a unique electronic signal such as a Coulomb Staircase and where such signal act as a diagnostic beacon and where such probe and a detector form a mesoscopic detector. The detector uses: a bioprobe containing the phage with its conjugated SET and the properties of the phage specificity; phage mobility within the biological environment and the phage ability to act as a carrier for the SET; and the SET's ultimate use as a beacon for the detection.