The disclosed methods are directed to preparing polypeptides for multi-attribute analysis. The polypeptides are optionally denatured, reduced, and/or alkylated before being subjected to a first digestion. Following the first digestion the large and small fragments resulting from the digestion are separated from each other. A second digestion is then performed on the larger of the fragments. All of the fragments from the two digestions are then analyzed chromatographically, electrophoretically, or spectrometrically, or a combination of these methods. The methods are especially useful for the preparation of therapeutic polypeptides for analysis, especially those that are not easily cleaved.

Provided are a stable triazolinedione adduct, a method for producing the same, a method for producing an ene compound, and a method for analyzing an ene compound. A triazolinedione adduct that is stable until the time of use and can be reacted while reverting to a triazolinedione compound at the time of use. Specifically, a triazolinedione adduct represented by formula (1). (In the formula, R.sup.1 is an organic group, and A is a fused ring of three or more rings including at least one aromatic ring.)

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The invention relates to a method for preparing lead (212) for medical use. This method comprises the production of lead (212) by the decay of radium (224) in a generator comprising a solid medium to which the radium (224) is bound, followed by the extraction of the lead (212) from the generator in the form of an aqueous solution A1, characterised in that the lead (212) contained in the aqueous solution A1 is purified from the radiological and chemical impurities, also contained in said aqueous solution, by a liquid chromatography on a column. The invention also relates to an apparatus specially designed for automated implementation in a closed system of said method. It further relates to lead (212) produced by means of this method and this apparatus. Applications: manufacture of radiopharmaceuticals based on lead (212), useful in nuclear medicine for the treatment of cancers, particularly by a-radioimmunotherapy, or for medical imaging, in both humans and animals.

Solutions, detection methods and chromatographic systems are provided for electrospray ionization of glycans modified with amphipathic, strongly basic moieties. The solutions for use in electrospray ionization comprise a plurality of glycans having an amphipathic moiety, a basic residue of pKa>5 and a Log P value between 1 and 3, and one or more volatile components selected from the group consisting of an amine, ammonia, ammonia salt, diethylamine, or trimethylamine. The solutions also have a pH between about 3 to about 6, and ionic strength of between about 0 mM to about 500 mM. The solutions are useful in detecting modified glycans in electrospray ionization and in various chromatographic systems.

Solutions, detection methods and chromatographic systems are provided for electrospray ionization of glycans modified with amphipathic, strongly basic moieties. The solutions for use in electrospray ionization comprise a plurality of glycans having an amphipathic moiety, a basic residue of pKa>5 and a Log P value between 1 and 3, and one or more volatile components selected from the group consisting of an amine, ammonia, ammonia salt, diethylamine, or trimethylamine. The solutions also have a pH between about 3 to about 6, and ionic strength of between about 0 mM to about 500 mM. The solutions are useful in detecting modified glycans in electrospray ionization and in various chromatographic systems.

An analysis method having: a sample preparation step of preparing a measurement sample by mixing a measurement object containing pyrroloquinoline quinone or a salt thereof with glycine so that the pyrroloquinoline quinone or the salt thereof reacts with the glycine to produce imidazopyrroloquinoline or a salt thereof; and a quantitative analysis step of determining quantitatively the amount of the pyrroloquinoline quinone and the salt thereof contained in the measurement object, based on a chromatogram of the imidazopyrroloquinoline or the salt thereof contained in the measurement sample obtained by chromatography.

A method for extracting and detecting volatile organic compounds includes steps as follows. At least one effervescent tablet is provided, wherein the effervescent tablet is produced by mixing an acidic compound and an alkaline compound homogeneously. An extraction and detection apparatus is provided, wherein the extraction and detection apparatus includes an extraction chamber, an injection tube and a detection instrument. An extraction step is performed, wherein a liquid matrix is put into the extraction chamber, and the effervescent tablet is added into the liquid matrix to generate bubbles, the volatile organic compounds are extracted from the liquid matrix by the bubbles, and the bubbles enter into the headspace of the extraction chamber. A detection step is performed, wherein the volatile organic compounds extracted during the extraction step are transferred to the detection instrument via the injection tube so as to detect the volatile organic compounds.

The present technology relates to a method of separating a sample comprising oligonucleotides. The method includes injecting a polyphosphonic acid at a concentration of between about 0.01 M to about 1 M into the sample comprising oligonucleotides. The method also includes flowing the sample and polyphosphonic acid through a liquid chromatography column and separating the oligonucleotides.

A method for simultaneously determining fat-soluble vitamins and carotenoids in serum, and belonging to the technical field of analytical chemistry, includes an ionic liquid (IL) or a binary mixed solvent composed of an IL and another solvent is adopted as an extractant; the biological samples are pre-treated by liquid-liquid extraction (LLE) and then detected by high-performance liquid chromatography (HPLC); retinyl acetate and trans-β-apo-8′-carotenal are adopted as the internal standards for fat-soluble vitamins and carotenoids, respectively; and the internal standard method is adopted to establish standard curves for quantification based on the retention time and the UV-Vis absorption spectrum. Compared with the existing methods, in the disclosure, the pretreatment process is simple and easy to be conducted, the sample can be prepared in a short time, and the toxic and harmful organic solvent is used at a reduced amount.

The present technology relates to a method for improved recovery of phosphorylated compounds (e.g., phosphorylated glycans). In particular, the present technology utilizes certain chelator additives in a solution to wash and elute the phosphorylated compounds from a solid phase extraction cartridge.