An electrode-modified heavy metal ion microfluidic detection chip, comprising a microfluidic module (1) and a three-electrode sensor (2), wherein the microfluidic module (1) is integrally molded by 3D printing, and the interior thereof has a microchannel (10) and a sensor slot (11); and the three-electrode sensor (2) comprises three electrodes (21, 22, 23) printed on a card-shaped bottom plate (20), among which the working electrode (21) is a porous nano-NiMn2O4 modified bare carbon electrode, and the three-electrode sensor (2) is inserted into the sensor slot (11) that matches same to form the microfluidic detection chip.

The present invention relates to the technical field of glucose detection, and in particular to an enzyme-free glucose sensor and a fabrication method and use thereof. In the present invention, Magnolia grandiflora L. leaves are used as a carbon-based catalyst, which serve as a base material to well disperse nickel atoms and improve the catalytic activity of a material. A prepared Ni@NSiC nano-molecular layer is used to modify a pretreated white glassy carbon electrode (GCE) to obtain a highly-active material-modified working electrode Ni@NSiC/GCE, and then glucose is detected through cyclic voltammetry (CV) and chronoamperometry (CA).

A microneedle biosensor includes a microneedle and a substrate. One end of the microneedle is connected to the substrate, an outer surface of the microneedle is provided with a working electrode and a first electrode, an outer surface of the working electrode is provided with an enzyme, and an outer surface of the microneedle biosensor is covered with a biocompatible film. A method for manufacturing a microneedle biosensor includes: manufacturing the substrate and the microneedle in an additive mode simultaneously; spray-printing and curing the working electrode and the first electrode on the outer surface of the microneedle; spray-printing and drying the enzyme on the outer surface of the working electrode; and using biocompatible liquid for spray-printing, and drying the biocompatible liquid to form the biocompatible film. The substrate, the microneedle, the working electrode, the first electrode, the enzyme and the biocompatible film are all manufactured through a full printing method.

A boron doped diamond electrode and its preparation method and application, the electrode is deposited with a boron or nitrogen doped diamond layer or a boron or nitrogen doped diamond layer composite layer on the surface of the electrode substrate, or after a transition layer is disposed on the surface of the substrate, a boron or nitrogen doped diamond layer or a composite layer of boron or nitrogen doped diamond layer is disposed on the surface of transition layer. The preparation method is depositing or plating a boron or nitrogen doped diamond layer on the surface of the electrode substrate, or providing a transition layer on the surface of the electrode substrate, and then depositing or plating a boron or nitrogen doped diamond layer or a composite layer of boron or nitrogen doped diamond layer on the surface of the transition layer.

An electrode 1 includes a resin film 2, a metal underlying layer 3, and an electrically conductive carbon layer 4 having sp.sup.2 bonding and sp.sup.3 bonding in order toward one side in a thickness direction. A ratio of the number of sp.sup.3-bonded atoms to the sum of the number of sp.sup.3-bonded atoms and the number of sp.sup.2-bonded atoms is 0.25 or more. A thickness of the metal underlying layer 3 is below 50 nm.

A method and a system for detecting heavy metal ions are provided. The method includes: fixing a pre-manufactured micro-electrode chip on a connecting device, connecting the connecting device to an electrochemical workstation, carrying out setting before detection on the electrochemical workstation, the micro-electrode chip including a counter electrode and a working electrode, carrying out graphene modification treatment on the counter electrode in advance, and carrying out bismuth film modification treatment on the working electrode in advance; and carrying out acid pretreatment on an aqueous solution to be detected, dropwise adding 5 .Math.L to 100 .Math.L of a treated aqueous solution to a working area of the pre-manufactured micro-electrode chip, measuring an I-V curve by the electrochemical workstation subjected to the setting before detection, and determining species and concentrations of heavy metal ions in the aqueous solution according to peak values of voltage and current of the I-V curve.

An embodiment provides a method for compensating for inteferants in measurement of alkalinity in a reagent-less system, including: introducing an aqueous sample into a measurement device comprising one or more series of electrodes; applying an electrical signal to the aqueous sample using the one or more series of electrodes, wherein the electrical signal is selected from the group consisting of: current and voltage; identifying, during application of the electrical signal, that the electrical signal reaches an oxidation threshold and measuring, prior to reaching the oxidation threshold, a first electrical response to the electrical signal, the first electrical response attributable to interferants in the aqueous sample; identifying, during application of the electrical signal, that the electrical signal reaches an endpoint and measuring, from the oxidation threshold to the endpoint, a second electrical response to the electrical signal; and measuring an alkalinity of the aqueous sample based upon a difference between the first electrical response and the second electrical response. Other aspects are described and claimed.

A method of using a graphite electrode to measure a concentration of glucose or methionine from a biological sample is described. A mechanical pencil lead may be used, as the graphite electrode, and the biological sample may come from a patient's serum. The glucose or methionine may produce a peak current response within a range of 0.4-0.8 V when the sample is subjected to linear scan voltammetry.

A source of formaldehyde for methylating a primary or secondary amine is part of an electrochemical measurement. The source of formaldehyde may be an adduct of formaldehyde.

Provided is an ionic-liquid-containing polymer capable of further downsizing a comparison electrode or the like and further improving the degree of freedom in design while reducing the manufacturing cost. The ionic-liquid-containing polymer used as a salt bridge of the comparison electrode contains an adhesive and a hydrophobic ionic liquid.