A carbon nanotube (CNT) assembled thin film modified steel wire array electrode, a preparation method and application thereof. The array electrode includes: a surface of a steel wire is negatively modified, and the surface of the steel wire is assembled with a plurality of layers of CNT thin films; one end of the steel wire is welded to a conductor, and a welding position between the steel wire and the conductor is wrapped with an insulating heat shrinkable tube; and the insulating template and the steel wire are encapsulated and cured by using an epoxy resin. The preparation method of the array electrode of the invention mainly includes the following steps: first, performing negative modification on a steel wire, then, assembling CNT thin films on the steel wire, and preparing the modified array steel wire into the CNT assembled thin film modified steel wire array electrode.

An electrochemical microsensor comprising an array of working microelectrodes, the working microelectrodes include: one or more bare microelectrodes; one or more thick film-coated microelectrodes, optionally with conductive additive incorporated into the coating, selected from the group consisting of polysaccharide-coated microelectrodes and platinum black-coated microelectrodes; one or more thin film-coated microelectrodes selected from the group consisting of reduced graphene oxide-coated microelectrode and transition metal chalcogenide-coated microelectrodes; wherein the electrochemical microsensor further comprises a counter electrode and optionally one or more reference microelectrode(s).

There is provided an electrochemical sensor, comprising: a working electrode; a counter electrode; and a base material supporting the working electrode and the counter electrode, wherein the working electrode is a chip-shaped electrode including a diamond film that causes a redox reaction on its surface when a predetermined voltage is applied in a state where a test sample exists between the working electrode and the counter electrode, and a support that comprises a material other than diamond and supports the diamond film, and the working electrode is mounted on the base material, with the support positioned on the base material side and at least a part of a side surface of the support exposed.

Provided is an electrochemical aptasensor for detecting di(2-ethylhexyl)phthalate (DEHP) with high sensitivity. The electrochemical aptasensor according to the present invention has a low detection limit concentration by improving sensitivity by sensor surface modification using a nano composite and gold nanoflowers, and has high practical applicability of a sensor by monitoring a trace amount of DEHP migrating from a real plastic product by a simple measurement method.

Systems, devices, and methods are described herein for using a biosensor to detect a target species in a biological sample by electrochemical methods. The systems include a biosensor comprising a working electrode, an anchor layer, a linker, and a recognition component. Optionally, the biosensor can also include a visualization component for characterization of the biosensor by one or more microscopy techniques. In some embodiments, the methods disclosed herein include mixing a reporter molecule with a biological sample to produce a mixture, flowing the resulting mixture over the biosensor, applying an excitation signal to the electrode to initiate a chemical reaction between the reporter molecule, the target species, and the biosensor, sensing a response signal from the biosensor in response to the excitation signal, and determining, based on the response to the excitation signal, the concentration of the target species present in the sample.

An electrochemical method for measuring the activity of enzymes using nanoelectrode arrays fabricated with vertically aligned carbon nanofibers. Short peptide substrates specific to disease-related enzymes are covalently attached to the exposed nanofiber tips. A redox moiety, such as ferrocene, can be linked at the distal end of the nanofibers. Contact of the arrays with a biological sample containing one or more target enzymes results in cleavage of the peptides and changes the redox signal of the redox moiety indicating the presence of the target enzymes.

The cathodized gold nanoparticle graphite pencil electrode is a sensitive enzymeless electrochemical glucose sensor based on the cathodization of AuNP-GPE. Cyclic voltammetry shows that advantageously, the cathodized AuNP-GPE is able to oxidize glucose partially at low potential (around −0.27 V). Fructose and sucrose cannot be oxidized at <0.1 V, thus the glucose oxidation peak at around −0.27 V is suitable enough for selective detection of glucose in the presence of fructose and sucrose. However, the glucose oxidation peak current at around −0.27 V is much lower which should be enhanced to obtain low detection limit. The AuNP-GPE cathodization increases the oxidation peak current of glucose at around −0.27 V. The dynamic range of the sensor is in the range between 0.05 to 5.0 mM of glucose with good linearity (R.sup.2=0.999). Almost no interference effect was observed for sensing of glucose in the presence of fructose, sucrose and NaCl.

A flow cell with a first section and a second section, and a gasket sealing between the first and second sections. A chamber is defined in the flow cell, having a perimeter with a narrower end and a rounded wider end. An inlet passage, outlet passage, and a sensor are arranged in fluid communication with the chamber. The inlet passage directs fluid into the chamber proximal its narrow end at an angle of between about 45° and 75° relative to the plane of gasket and the outlet passage directs fluid flow out of the wider end of the chamber at an angle between about 45° and 75° relative to the plane of gasket, the inlet passage and outlet passage being angled in opposite directions. The flow cell is useful for monitoring levels of chemicals in an industrial process stream, such as lactose levels in a dairy process stream.

The present disclosure relates to an electrode for measuring an analyte. The electrode includes a first base layer, a first electrode layer upon the first base layer, and a second base layer. The first electrode layer is arranged between the first base layer and the second base layer. The first base layer includes a conductive metal, a conductive metal alloy, or carbon. The first electrode layer includes ruthenium metal, a ruthenium based metal alloy, nickel metal, or a nickel based metal alloy. The first base layer is made of different elements than the first electrode layer. The first base layer is more conductive than the first electrode layer.

A device for measuring pH levels and contaminant concentration includes an electrode assembly that is electrically coupled to a control unit. The electrode assembly includes a FLUID first contact electrically coupled to a reference electrode, a second contact electrically coupled to a working electrode, and a third contact electrically coupled to a counter electrode. The working electrode may be modified to include a cysteine functionalized graphene oxide with polypyrrole nanocomposite. In operation, the control unit may apply a complex signal to the working electrode via the second contact in order to adhere and subsequently strip contaminant ions from the fluid sample to the working electrode. During this process, a current may be measured across the reference electrode and the counter electrode to measure contaminant ion concentration. The pH of the fluid sample may also be determined by a current measured across the reference electrode and the counter electrode. In some examples, the pH may be used to calibrate the measured levels of the contaminant ions.