A method may include maintaining a sample comprising an ionic species and an optical indicator at an elevated temperature above 25° C. on a semi-conductive microfluidic die during an incubation period, intermittently interrogating the sample with an interrogating light during the incubation period and sensing a response of the sample to the interrogating light, wherein the sample is interrogated with the interrogating light only during those times at which the sample is being sensed.

An embodiment provides a method for measuring total chlorine in a solution, including: preparing a thiocarbamate indicator; introducing the thiocarbamate indicator to a solution, wherein the solution contains an amount of monochloramine; adding an additive to the solution, wherein the additive accelerates the reaction rate between the thiocarbamate indicator and monochloramine and causes a change in fluorescence of the solution; and measuring the amount of monochloramine in the solution by measuring an intensity of the fluorescence. Other aspects are described and claimed.

Certain embodiments provide a marker for detecting a detection target substance, including an assay reagent having a medium, and a composition containing a solvent or a solvent mixture, and a fluorescent coagulation factor that has a fluorescence property that changes as it coagulates in presence of the detection target substance. A difference of a hydrophobicity parameter LogP between the solvent and a part or the entirety of the detection target substance is equal to or smaller than 1.53.

A method for measuring phototoxicity or photoallergy includes reacting a test substance with an organic compound that is an N-(arylalkylcarbonyl)cysteine or an α-N-(arylalkylcarbonyl)lysine under irradiation with ultraviolet light; reacting the test substance with the organic compound without irradiation with ultraviolet light; determining the depletion of the organic compound after each reaction by an optical measurement; and detecting phototoxicity or photoallergy from the difference between the depletion of the organic compound after the reaction under irradiation with ultraviolet light and the depletion of the organic compound after the reaction without irradiation with ultraviolet light.

A test sensor for determining an analyte concertation in a biological fluid comprises a strip including a fluid receiving area and port-insertion region. A first row of optically transparent and non-transparent positions forms a calibration code pattern disposed within a first area of the port-insertion region. A second row of optically transparent and non-transparent positions forms a synchronization code pattern disposed within a second area of the port-insertion region. The second area is different from the first area. The synchronization code pattern corresponds to the calibration code pattern such that the synchronization code pattern provides synchronization of the serial calibration code pattern during insertion of the port-insertion region into the receiving port of the analyte meter.

Provided herein is technology relating to sensors for detecting an analyte and particularly, but not exclusively, to liquid crystal sensors, methods of producing liquid crystal sensors, and methods of using liquid crystal sensors.

Kits and methods are provided for performing multiplex LAMP reactions. These kits and methods are directed to specific and sensitive methods of target nucleic acid detection and more specifically pathogen diagnostics such as detection of Coronavirus. The kits and methods utilize a plurality of sets of oligonucleotide primers for targeting the viral nucleic acid target.

Herein reported are new tricyclic cytidine compounds, such as 8-diethylamino-tC (8-DEA-tC), that respond to DNA and/or RNA duplex formation with up to a 20-fold increase in fluorescent quantum yield as compared with the free nucleoside, depending on neighboring bases. This turn-on response to duplex formation is by far the greatest of any reported nucleoside analogue that can participate in Watson-Crick base pairing. Measurements of the quantum yield of 8-DEA-tC mispaired with adenosine and, separately, opposite an abasic site show that there is almost no fluorescence increase without the formation of correct Watson-Crick hydrogen bonds. Kinetic isotope effects from the use of deuterated buffer show that the duplex protects 8-DEA-tC against quenching by excited state proton transfer. DFT calculations provide a rationale for the observed photophysical properties that is dependent on duplex integrity and the electronic structure of the analogue.

The present disclosure relates to probes for analyzing a chemical composition, and related methods of analyzing a chemical composition and of manufacturing probes for analyzing a chemical composition. A benefit of the disclosed probes and methods can include luminescent chemical sensor arrays for rapid, accurate, portable and economical qualitative and quantitative analysis of a broad range of chemical compositions. A benefit of the methods disclosed herein can include the rapid, simple, and accurate analysis of trace chemicals present in chemical compositions.

Disease infection in a plant can be detected at an early stage by utilizing a boron-oxygen compound having a specific structure 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.