A fiber-optic sensing apparatus, system, and method for characterizing at least one metal ion in a solution are provided. The sensing apparatus includes a fiber-optic sensor and a controller. The sensor includes an optical fiber with tilted grating in its core, and includes a conductive and surface plasmon resonance (SPR)-active coating assembly that allows the sensor to also serve as an electrochemical working electrode. The controller is electrically connected with the sensor, configured to provide an adjustable potential such that when the coating assembly is in contact with the solution, redox reactions of each of the at least one metal ion occur on an outer surface thereof, resulting in a detectable change of the surface plasmon waves generated in the fiber-optic sensor. Based on the change thus detected, identities and/or concentration of the at least one metal ion in the solution can be determined with high accuracy and sensitivity.

The ion sensor of the present invention is a current measurement type ion sensor that measures a current to measure a target ion, and includes an organic phase retaining layer containing an organic phase capable of forming an interface with the sample containing the target ion, a first electrode to which the organic phase retaining layer is laminated and containing a first insertion material composed of an inorganic compound, a second electrode arranged so as to face the organic phase holding layer and in contact with the sample.

Apparatus and methods are provided for measuring phosphate in water. The methods can involve electrically pre-treating a potentiometric sensor and using the electrically pre-treated potentiometric sensor in a water sample to obtain a phosphate measurement. The potentiometric sensor includes a working electrode and a counter electrode. The working electrode includes a metal/metal oxide electrode having a detection surface. The electrical pre-treatment generates a metal phosphate on the detection surface of the metal/metal oxide electrode. The phosphate measurement results in a fresh layer of mixed oxide on the detection surface of the metal/metal oxide electrode. The electrically pre-treatment can be performed in situ in the water sample, allowing for field monitoring of water bodies. In some embodiments, the method can also involve cleaning the sensor prior to electrically pre-treating the sensor or after obtaining the phosphate measurement.

The present disclosure describes a measuring system, comprising: a housing; a first chamber formed in the housing; arranged in the first chamber, a measuring cell, which includes a container embodied for receiving an electrolyte and at least one electrode for potentiometric and/or amperometric measurements, wherein the at least one electrode has a first section, which is arranged within the container, and a second section, which extends out from the container into the first chamber; and a temperature regulating apparatus, which is embodied to produce a temperature-controlled gas stream moving through the first chamber and flowing around the measuring cell, especially the container and the section of the at least one electrode extending from the container lid into the first chamber.

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 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.

Method and system for detection and quantification of oxidizable organics in water. The method involves the partial electrolytic decomposition of the oxidizable organics in a short time frame, preferably less than five seconds, and does not involve the use of toxic reagents. The system includes an electrochemical sensor probe that, in turn, includes a boron-doped diamond microelectrode array. The system additionally includes an electronic transducer and a computing device. The system utilizes an analysis technique to convert sensor signal to a result that can be correlated with COD or BOD values obtained by standard methods. The method and system are particularly suitable for, but not limited to, use in monitoring of water quality at wastewater treatment plants. By employing the method before and after adding aerobic microorganisms to the sample, the method may be used to distinguish biologically oxidizable organics from total oxidizable organics.

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 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.