A water quality measurement apparatus is provided. The apparatus comprises an electrochemical cell, a pH sensor, a temperature sensor, a control circuit, a power source, a database, and a warning device. The electrochemical cell comprises a working electrode, a reference electrode, and a counter electrode. The control circuit provides predetermined adjustable potentials between the reference electrode and the working electrode and measures electrochemical currents between the working electrode and the counter electrode, to form a current diagram based on the predetermined adjustable potentials and the electrochemical currents. The database stores predetermined reference diagrams based on various pH values and temperatures, and is in communication with the control circuit. The warning device is configured to output warnings, wherein the control circuit triggers the warning device in the condition that the current diagram exceeds the predetermined reference diagram based on the same range of the pH values and the temperatures.

A water quality measurement apparatus is provided. The apparatus comprises an electrochemical cell, a pH sensor, a temperature sensor, a control circuit, a power source, a database, and a warning device. The electrochemical cell comprises a working electrode, a reference electrode, and a counter electrode. The control circuit provides predetermined adjustable potentials between the reference electrode and the working electrode and measures electrochemical currents between the working electrode and the counter electrode, to form a current diagram based on the predetermined adjustable potentials and the electrochemical currents. The database stores predetermined reference diagrams based on various pH values and temperatures, and is in communication with the control circuit. The warning device is configured to output warnings, wherein the control circuit triggers the warning device in the condition that the current diagram exceeds the predetermined reference diagram based on the same range of the pH values and the temperatures.

Provided is a method for detecting a test substance. In this method, metal is deposited or a complex containing a test substance and a metal particle is immobilized on a working electrode on an electrode substrate including the working electrode and a counter electrode. An oxidation potential is applied to the working electrode to generate metal ions, then a reduction potential is applied to a portion having an area smaller than an area of the portion to which an oxidation potential is applied in the working electrode to deposit metal on the surface of the portion to which the reduction potential is applied, and current, voltage or charge caused by the metal deposited is measured to detect metal ions or a test substance.

Provided is a method for detecting a test substance. In this method, metal is deposited or a complex containing a test substance and a metal particle is immobilized on a working electrode on an electrode substrate including the working electrode and a counter electrode. An oxidation potential is applied to the working electrode to generate metal ions, then a reduction potential is applied to a portion having an area smaller than an area of the portion to which an oxidation potential is applied in the working electrode to deposit metal on the surface of the portion to which the reduction potential is applied, and current, voltage or charge caused by the metal deposited is measured to detect metal ions or a test substance.

A computer-implemented method for interpreting an electrochemical response, comprises the steps of: (a) providing an electrochemical response that is baseline-corrected; (b) identifying in the electrochemical response one or more peaks that exceed a predetermined height threshold and a predetermined prominence threshold, each identified peak having a peak position; (c) providing a predetermined peak position range for each of a plurality of analytes; and (d) attributing one or more of the analytes to the peaks identified in step b, by, for each peak, associating the peak with an analyte when the peak position falls within the predetermined peak position range for the analyte.

A computer-implemented method for interpreting an electrochemical response, comprises the steps of: (a) providing an electrochemical response that is baseline-corrected; (b) identifying in the electrochemical response one or more peaks that exceed a predetermined height threshold and a predetermined prominence threshold, each identified peak having a peak position; (c) providing a predetermined peak position range for each of a plurality of analytes; and (d) attributing one or more of the analytes to the peaks identified in step b, by, for each peak, associating the peak with an analyte when the peak position falls within the predetermined peak position range for the analyte.

Provided is a method for sensing methyl salicylate, which is a plant hormone released when a plant is infected with a disease in cultivation of plants including agricultural crops, and thereby provided a method for early in-situ detection of disease infection in a plant. With the present embodiment, disease infection in a plant can be detected at an early stage by utilizing a rare earth compound that selectively recognizes and forms a complex with methyl salicylate, which is a plant hormone released when a plant is infected by a pathogen, as a receptor for sensing, and by utilizing a fluorescence emission phenomenon and a change in electrochemical behavior after the reaction with methyl salicylate.

Provided is a method for sensing methyl salicylate, which is a plant hormone released when a plant is infected with a disease in cultivation of plants including agricultural crops, and thereby provided a method for early in-situ detection of disease infection in a plant. With the present embodiment, disease infection in a plant can be detected at an early stage by utilizing a rare earth compound that selectively recognizes and forms a complex with methyl salicylate, which is a plant hormone released when a plant is infected by a pathogen, as a receptor for sensing, and by utilizing a fluorescence emission phenomenon and a change in electrochemical behavior after the reaction with methyl salicylate.

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 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.