The present disclosure relates to a pH sensor for determining the pH of an aqueous medium at least comprising a polymeric matrix comprising embedded phosphorescent nanoparticles and one or more embedded fluorescent dyes, wherein the phosphorescent nanoparticles comprise transition metal complexes having central atoms selected from the group consisting of Ru, Re, Os, Rh, Ir, Pt and the fluorescent dye comprises fluorescein derivatives according to the following formula I

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or charged structures thereof, wherein n is greater than or equal to 5 and less than or equal to 20, X═—O—, —OH, —OR.sup.4, —NH.sub.2, —NH— or NHR.sup.4, wherein R.sup.4 is selected from the group consisting of C1-C20 alkyl and the R.sup.1, R.sup.1′, R.sup.2, R.sup.3 are independently selected from the group consisting of H, D, substituted or unsubstituted C1-C20 alkyl and halogen. Furthermore, the present disclosure comprises a method and a system for determining pH.

The present invention teaches an apparatus for consistent and accurate on-site readings of fluorescence signals of coronavirus test result, with which a user directly reads a fluorescent light qualitatively instead of using electronic sensors. The fluorescent light is excited from a fluorescent source in a site of interest in a target assay. The device comprises a light source for generating an excitation light for exciting the fluorescent source of the target assay to generate a fluorescent light, a component for accurately transmitting the excitation light and the fluorescent light with less noise or reflection, a component for consistent detecting of the fluorescent source by bare eyes with minimal health risks, and a user control system that requires minimal training.

Arrays of integrated analytical devices and their methods for production are provided. The arrays are useful in the analysis of highly multiplexed optical reactions in large numbers at high densities, including biochemical reactions, such as nucleic acid sequencing reactions. The devices allow the highly sensitive discrimination of optical signals using features such as spectra, amplitude, and time resolution, or combinations thereof. The devices include an integrated diffractive beam shaping element that provides for the spatial separation of light emitted from the optical reactions.

An embodiment provides a method for measuring mercury in a solution, including: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator to a solution, wherein the solution contains an amount of mercury and the introducing causes a change in fluorescence of the solution; and measuring the amount of mercury in the solution by measuring a change in intensity of the fluorescence. Other aspects are described and claimed.

The sensing arrangement (1), comprising:—a sensing area (10), for accommodating a sensing substance (20) selected for experimenting an optical response as a response of an external stimulus;—a light emitter (11), for emitting light towards said sensing area (10);—a light receiver (12), for receiving a light from said sensing area (10);—a substrate (13) having a first substrate surface (131) and a second substrate surface (132); wherein, said light emitter (11) comprise a first LED (110) and said light receiver (12) comprise a second LED (120), both LEDs (110, 120) formed on said first substrate surface (131); and said sensing arrangement (1) further comprises a trench (14), formed between said first LED (110) and said second LED (120).

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.

A pH photothermal spectrometer includes a container that receives an analyte medium and pH-sensitive chromophore. An excitation fiber and optical thermometer are disposed in the container. The optical thermometer include a light receiver disposed on a temperature detector fiber.

A detection system and a portable detection device for detecting an object of interest in a lateral flow immunoassay strip. The lateral flow immunoassay strip has a detection carrier and a reporter, the detection carrier has a control zone and a test zone. The detection system has a laser light source, a scanning and spatial modulation module, a signal acquisition assembly, and a processing device. The laser light source provides a laser light. The scanning and spatial modulation module receives the laser light, and then provides a scanning and spatially modulating laser beam for irradiating a lateral flow immunoassay strip to generate a detecting signal. The signal acquisition assembly receives the detecting signal. The processing device electronic connects to the signal acquisition assembly and receives the detecting signal from the signal acquisition assembly.

A time-resolved fluorescence immunochromatographic test paper card for testing clothianidin. A binding pad includes a detection microsphere and a quality control microsphere thereon, wherein the detection microsphere is a fluorescent microsphere coated with a clothianidin monoclonal antibody on the surface thereof, the quality control microsphere is a fluorescent microsphere coated with a rabbit anti-tag protein on the surface thereof. An NC film is provided with a detection line and a control line. The lengths of the detection line and the control line are the same as the width of the NC film. A first clamping part is arranged at one end of the sample pad. A second clamping part and a third clamping part are respectively arranged at two ends of the binding pad. A fourth clamping part is arranged at one end of the NC film, the other end of the NC film is joined with an absorption pad.

A one-way relief valve for hermetically sealed packages is disclosed, wherein said valve comprises a valve body (100) made of a lower support surface (102) provided with vent holes (101) and a flexible membrane (110) associated with said lower support surface (102) that is capable of switching between a configuration in which the valve is closed and a configuration in which the valve is open. Said membrane (110) is characterised in that it is coloured, in order to facilitate visual inspection by the operator or the machine during the assembly of the valve and/or the production of hermetically sealed packages provided with the valve.