The invention relates to a chromatography method of producing a target elution volume comprising a first and a second target protein. The method includes providing a cation exchange chromatography column; applying a protein solution on the column, the protein solution comprising the first target protein, a second target protein and optionally one or more further proteins; inputting an optimization criterion; computing chromatography simulations for computing an elution buffer salt concentration adapted to provide a target elution volume matching the optimization criterion best; computing the pooling borders of the target elution volume as a function of at least the computed salt concentration and the input optimization criterion; applying an elution buffer having the computed salt concentration on the chromatography column; performing the elution; and collecting the computed target elution volume.

A method of analyzing phenylhydrazine content in a 3-methyl-1-phenyl-2-pyrazolin-5-one active pharmaceutical ingredient includes obtaining a first measured value by measuring a phenylhydrazine content of a standard solution including phenylhydrazine or a salt thereof, a first acidic water and a first water-soluble organic solvent and having a phenylhydrazine concentration of 0.01 μg/mL to 10 μg/mL, obtaining a second measured value by measuring a phenylhydrazine content in a sample solution including a 3-methyl-1-phenyl-2-pyrazolin-5-one active pharmaceutical ingredient, a second acidic water and a second water-soluble organic solvent, and detecting a phenylhydrazine content in a 3-methyl-1-phenyl-2-pyrazolin-5-one active pharmaceutical ingredient based on the first measured value and second measured value. The first acidic water is hydrochloric acid, and/or an aqueous acetic acid solution, the first water-soluble organic solvent is acetonitrile and/or methanol, the second acidic water is hydrochloric acid, and/or an aqueous acetic acid solution, and the second water-soluble organic solvent is acetonitrile and/or methanol.

A process and system for monitoring and controlling the operation of a dehydrogenation reactor is provided. Samples of hydrocarbon streams are taken at sampling locations to be analyzed at a single gas chromatograph or other analytical equipment. Actions can be taken to modify the operation of the dehydrogenation reactor as necessary to maintain its operation within predetermined parameters. In particular, actions may be taken when a hydrocarbon stream exhibits an amount of cracking that is outside parameters. It is usually intended that actions will be taken on a gradual basis once or twice per day to reduce the cost of the process while still providing the necessary changes to operations.

An object is to provide a high performance liquid chromatography method which enables quantitative analysis with the stability of reduced pyrroloquinoline quinone under measurement conditions maintained. The object can be achieved by the following method. A high performance liquid chromatography analysis method, comprising: a sample preparation step of preparing a sample for high performance liquid chromatography containing reduced pyrroloquinoline quinone or a salt thereof from a specimen and a separation step of separating the reduced pyrroloquinoline quinone or a salt thereof contained in the sample for high performance liquid chromatography from the specimen using interaction between a stationary phase and a mobile phase by a high performance liquid chromatography method using a reversed phase column as the stationary phase and using an eluent comprising 0.050 to 1.5% by mass of phosphoric acid and/or hydrochloric acid and 20 to 50% by volume of methanol and/or acetonitrile as the mobile phase.

An object of the present invention is to provide a reagent for measuring skin sensitization that can measure sensitization to a test substance with high sensitivity using a single type of reagent; a compound; and a method for measuring skin sensitization. According to the present invention, provided are a reagent for measuring skin sensitization including, as a main measuring agent, an organic compound having a mercapto group and a hydrazide structure and having an absorption spectrum in an ultraviolet, visible, or near-infrared region; a compound for use in the reagent for measuring skin sensitization; and a method for measuring skin sensitization using the reagent for measuring skin sensitization.

The present invention relates to a dianhydride analysis method. The method can stably analyze a dianhydride which has high reactivity and low solubility. Furthermore, the method can minimize the problem that a reaction product disturbs an analysis result, thereby improving accuracy of the analysis result.

A sample preparation kit related to the present invention provides a significantly versatile analytical technique that is not affected by the diversity of antibodies, difference in species, matrix and the like. For preparing a sample to be used for detection of a monoclonal antibody through high-performance liquid chromatography-mass spectrometry (LC-MS), the kit includes a porous body for immobilizing a monoclonal antibody to be detected; nanoparticles with an immobilized protease; a reaction vessel for selectively digesting the monoclonal antibody by bringing the porous body and nanoparticles into contact; a buffer to be introduced into the reaction vessel along with the nanoparticles and porous body so that a protease reaction is carried out; and a filtration membrane to remove the porous body and nanoparticles after the proteolysis so as to extract the reaction product and the buffer.

A method for analyzing aromatic compounds, and a reagent kit for LC-MS analysis of aromatic compounds. The method includes preparing a diazonium reagent, contacting aromatic compounds in a sample with the diazonium reagent to form an analyte; and measuring an amount or ratio of the analyte. The reagent kit includes a diazonium reagent, wherein the diazonium reagent includes (i) a diazonium salt that contains a diazonium ion; (ii) an amine and nitrous acid; and/or (iii) a nitrite and an acid.

The present invention discloses a quantitative detection method of multiple metabolic components in a biological sample and a metabolic chip used in the method. The detection method includes performing derivatization treatment on the biological sample and then detecting the derivatized biological sample by liquid chromatography-mass spectrometry. During derivatization treatment, 3-nitrophenylhydrazine is used as a derivatization reagent, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide is used as a derivatization reaction catalyst. According to the detection method of the present invention, high-sensitivity detection can be achieved, multiple metabolic components of different magnitudes can be detected, the operation is simple and fast, and the method is applicable to clinical detection and scientific research examination. The metabolic chip of the present invention includes a chip carrier microtiter plate and related reagents, and quantitative detection of multiple metabolic components of different magnitudes such as amino acid, phenol, phenyl or benzyl derivative, indole, organic acid, fatty acid, sugar, and bile acid in the biological sample on the same microtiter plate can be achieved.

A liquid leak detection device is used in an oven. The oven has an oven casing having a sealed inner space provided with a sample flow path through which a liquid sample flows and a heater provided in the inner space that heats the inner space. The liquid leak detection device includes a gas sensor that is provided in the inner space and detects a liquid sample that has leaked from the sample flow path to the inner space and has been evaporated. The liquid leak detection device further includes a liquid leak pipe path that communicates with the inner space and leads a non-vaporized liquid sample that has leaked from the sample flow path to the inner space out of the oven casing, and a liquid sensor that is provided outside of the oven casing and detects a liquid sample led out by the liquid leak pipe path.