Abstract: This disclosure relates to methods of detecting iron in a water injection system, such as a water injection system used in the oil and gas industry, using an optical siderophore-based biosensor. This disclosure also relates to methods of detecting corrosion using an optical siderophore-based biosensor.

Abstract: Methods of collecting diffraction patterns from a microcrystal having an ordered array of a molecule are disclosed, which include using an exposure rate of at most 0.02 electrons per square angstrom per second on the microcrystal and using a direct electron detector to record electron diffraction patterns. Also disclosed are methods of determining a structural model for a molecule, identifying a material present in a trace amount within a sample, identifying a polymorph, and identifying the stereochemistry of a molecule.

Abstract: A multifunctional detection test kit includes a water test paper including a base and a plurality of test modules provided on different test zones of the base. Each of the test modules is configured to detect one of pH value, total alkalinity, cyanuric acid, total chlorine, bromine, free chlorine water hardness, lead, iron, copper, nitrite, nitrate, MPS, nickel, and phosphate.

Abstract: Disclosed herein are methods and kits employing a colorimetric test wherein the presence of beryllium is indicated by a visible color change. Advantageously, according to embodiments, when the dye containing substrate contacts beryllium, the color change occurs almost instantly, allowing for rapid, near-real-time detection of beryllium without the use of complex instrumentation.

Abstract: A device and its use for the direct quantification of Aflatoxin M1 (AFM1) in a sample of milk, the use includes a) providing a sample of milk; b) irradiating the sample of milk of step a) with a first electromagnetic radiation which includes at least one wavelength in a range from 340 to 400 nm; c) detecting a second electromagnetic radiation, emitted by the sample of milk of step b), in a range from 410 to 860 nm; d) selecting at least 9 wavelengths in a range from 410 to 860 nm of the second electromagnetic radiation detected in step c); and e) quantifying the Aflatoxin M1 (AFM1) in the sample of milk, on the basis of an intensity of the radiation emitted by the wavelengths selected in step d).

Abstract: Color-based (colorimetric) breast milk analyses using test strips (paper-based assays) read with the smartphone camera to quantify the concentration in accordance with embodiments of the invention are disclosed. In one embodiment, a color-based strip for testing breast milk is provided, the strip including: a first portion including a protein reagent pad where exposing the protein reagent pad to breast milk results in a first reaction for measurement of total protein concentration in the breast milk, a second portion including a fat reagent pad where exposing the fat reagent pad to breast milk results in a second reaction for measurement of fat concentration in the breast milk, and a third portion that is or includes a lactose reagent pad where exposing the lactose reagent pad to breast milk results in a third reaction for measurement of lactose concentration in the breast milk.

Abstract: A method for determining a combined amount of ?-tocopherol and ?-tocopherol in a sample by tandem mass spectrometry includes subjecting the sample to ionization under conditions suitable to produce one or more ions from the ?-tocopherol and ?-tocopherol detectable by mass spectrometry; and determining the amount of one or more of the ions by tandem mass spectrometry. Tandem mass spectrometry methods of this disclosure involve fragmenting ?-tocopherol and ?-tocopherol ions having a mass to charge ratio of about 416.35±0.80 into one or more fragment ions including a fragment ion having a mass to charge ratio of about 151.00±0.80, wherein the amount of the one or more ions determined is related to the combined amount of ?-tocopherol and ?-tocopherol in the sample.

Abstract: This invention describes a method for preparation of stable hematology reference materials by producing synthetic hydrogel blood cell surrogates, which mimic human blood components in size, morphology, performance and functionality when analyzed using an automated hematology analyzer employing multiple detection technologies. Different hydrogel particles can be combined and mixed to prepare multi-parameter and multi-level hematology reference materials, which could be used for calibration, linearity verification, proficiency evaluation, and routine performance monitoring of modern automated hematology analyzers. These hydrogel particles can also be combined with processed and stabilized human blood components to prepare the reference materials of this invention.

Abstract: Described herein are compositions that are suitable for use in analyte sensing in biological samples and in medical diagnostics. The compositions include an oxidase capable of oxidizing the analyte of interest to produce hydrogen peroxide, a peroxidase, and a chemical compound, such as a near-infrared fluorescent compound, that is a substrate for the peroxidase. The oxidase, the peroxidase, and the chemical compound are encapsulated by vesicle that includes a lipid or polymeric bilayer, such as liposome and polymersome. The peroxidase catalyzes the oxidation of the chemical compound by hydrogen peroxide. Methods of analyte sensing in biological samples using these compositions, and methods of preparing the compositions are also described.

Abstract: Methods for treating and differential diagnosis between ACTH-Dependent and ACTH-Independent Cushing's syndrome are disclosed, in which a glucocorticoid receptor antagonist (GRA) is administered to a Cushing's syndrome patient with a basal ACTH level less than about 25 pg/mL. If i) the patients blood ACTH and ii) the patients blood cortisol, or adrenal hormone, or adrenal pre-hormone levels rise, or if the ACTH:cortisol ratio increases, then ACTH-Dependent Cushing's syndrome is diagnosed. If those levels do not rise, or if the ACTH:cortisol ratio decreases, then ACTH-Independent Cushing's syndrome is diagnosed. In some instances, the patient is recovering from surgery to remove an ACTH secreting tumor, and the method described herein is used to determine if the tumor resection was successful or complete.

Abstract: A method for characterizing a melting transition in a semicrystalline polymer is disclosed. The method includes incorporating a fluorophore into the semicrystalline polymer, changing a temperature of the semicrystalline polymer to vary across a range of temperatures including a plurality of temperatures, and capturing an emission spectrum of the incorporated fluorophore at each temperature of the plurality of temperatures. The method also includes integrating each emission spectrum to determine a temperature-dependent integrated fluorescence intensity for the semicrystalline polymer, numerically differentiating the temperature-dependent integrated fluorescence intensity, and characterizing the melting transition of the semicrystalline polymer by identifying a stepwise change in value of the differentiated intensity. The semicrystalline polymer may be a thermoplastic.

Abstract: A method for measuring characteristics of particles in solution and to a device for performing the same, wherein the method includes the steps of providing a vessel containing a sample of the particles in solution, wherein the sample has preferably a volume between 0.1 ?L and 15 ?L, providing a monochromatic light source and a light detector, transmitting light from the monochromatic light source to the vessel containing the sample, detecting light emitted from the vessel with the light detector, and determining characteristics of the particles in solution in the sample based on a dynamic light scattering (DLS) measurement.

Abstract: A method of atmospheric inorganic and organic nitrogen quantification is disclosed. The ambient air is sampled by drawing it through an inlet followed by a denuder to reduce positive artifacts. After artifact removal, the air sample is collected onto a filter. The filter is subjected to thermal evolution under stepwise temperature program to generate a gaseous product mixture. In the presence of oxygen-containing carrier gas, the gaseous product mixture is oxidized to form oxidized gaseous products of CO2 and nitrogen oxides. Then, the nitrogen oxides products are processed to form an NO product and reacted with ozone to form an excited NO2* molecule. By quantifying the intensity of fluorescence, the concentration of NO2* molecule is measured, which determines the nitrogen content in the aerosol sample. The differentiation of inorganic and organic nitrogen is achieved through processing the thermally evolved carbon and nitrogen signals using multivariate curve resolution data treatment.

Abstract: A method for detecting labile zinc (Zn2+) in a biological material is provided herein, the method including: (a) contacting the biological material with a composition including NapBu-BPEA; and (b) imaging the biological material via molecular fluorescence imaging to detect the labile zinc in the biological material. Also provided herein are methods for morphology-correlated detection of labile zinc localization in a subcellular organelle of a living cell and methods for tracking a change in labile zinc localization in a biological material.

Abstract: Devices and methods for using changes in the orientation of micrometer sized dispersed liquid crystal domains to detect or quantify analytes in a test sample, including amphiphilic analytes, are disclosed. The dispersed liquid crystal domains are defined by an interface, and one or more nanoparticles or nanoparticle-containing complexes are adsorbed to the interface. As a result of the adsorption of the nanoparticles or nanoparticle-containing complexes at the interface, the microdomains are stabilized, and resist coalescing for extended periods of time, unlike previously known devices using liquid crystal emulsions for analyte detection. When the dispersed liquid crystal microdomains are exposed to the test sample, any changes in the orientation of the liquid crystal microdomains (such as from the bipolar to radial) are detected.

Abstract: A method and device for detecting urea are provided. The method for detecting urea includes the following steps. A derivatization reagent reacts with a sample to obtain a mixture, wherein a reaction time period for reacting urea in the sample with the derivatization reagent to form a derivative product is controlled. The derivative product is separated from the mixture. The amount of separated derivative product is analyzed to determine the concentration of urea in the sample.

Abstract: The present disclosure provides in vitro methods for identifying the presence or absence of haemoglobin S (HbS) or haemoglobin C (HbC) in a blood sample, kits and devices thereof. The inventors have found that HbS shows a substantial decrease in absorption under deoxygenated conditions compared to oxygenated conditions. The inventors expect HbC to show a similar decrease in absorption under deoxygenated conditions compared to oxygenated conditions. The methods, kits and devices of the disclosure employ this decrease in absorption under deoxygenated conditions to identify the presence or absence of HbS or HbC in a blood sample. The methods, kits and devices of the present disclosure are simple, low cost, and provide a rapid way to identify the presence or absence of HbS or HbC in a blood sample in a point-of-care setting.

Abstract: Methods of identifying a sequence of a polypeptide within a heterogenous mixture of polypeptides, the polypeptide being immobilized to a support and having at least one labeled amino acid residue. Methods involve detecting at least one signal or signal change from the immobilized polypeptide and subjecting the polypeptide to conditions sufficient to remove at least one amino acid residue from the polypeptide.

Abstract: An assay system includes an excitation light source to output excitation light having a first wavelength; an optical reference positioned to absorb the excitation light from the excitation light source and to output an optical signal based on the excitation light, where the optical signal has a second wavelength that is different from the first wavelength; a reaction chamber containing a reactant and an inlet to receive a test sample to produce a fluid that is based on the test sample and the reactant, where the reaction chamber is positioned to receive the optical signal from the optical reference; and an optical receiver positioned to detect an amount of the optical signal that passed through the reaction chamber containing the fluid.

Abstract: Provided is a method for accurately measuring coagulation time of blood samples showing various coagulation reactions. The method for measuring blood coagulation time includes measuring coagulation reaction of a sample prepared by mixing a subject specimen and a coagulation time measurement reagent; calculating weighted average time of a calculation target area of a waveform related to coagulation velocity from the resulting measurement data; and determining the weighted average time as blood coagulation time.