Abstract: One mode of a method for analyzing acylcarnitine according to the present invention is a method for analyzing C5 acylcarnitine using a tandem mass spectrometer, the method including: a measurement step of performing MRM measurement on a specimen according to at least one of MRM transitions of m/z 24>187, m/z 246>57, m/z 246>41, and m/z 246>29; and a processing step of distinguishing between isovalerylcarnitine and pivaloylcarnitine which is an isomer of isovalervicarnitine in the specimen or determining whether or not C5 acylcarnitine in the specimen includes pivaloylcarnitine, using a measurement result obtained in the measurement step. This makes it possible to satisfactorily distinguish between isovalerylcarnitine and pivaloylcarnitine, which have been conventionally difficult to distinguish.

Abstract: An analysis method includes: performing liquid chromatography using a mobile phase including an adsorption prevention agent for preventing adsorption of a sample including a compound having a phosphate group to metal; and performing mass spectrometry on an eluate of the liquid chromatography. The adsorption prevention agent includes an oxalic acid or a salt of the oxalic acid.

Abstract: An analysis method includes: performing liquid chromatography using a mobile phase including an adsorption prevention agent for preventing adsorption of a sample including a compound having a phosphate group to metal; and performing mass spectrometry on an eluate of the liquid chromatography. The adsorption prevention agent includes an oxalic acid or a salt of the oxalic acid.

Abstract: Provided is a method by which the disaccharides derived from glycosaminoglycans can be analyzed in a stable and highly reproduceable manner. A method for analyzing a glycosaminoglycan according to the present invention includes: a first process for producing a plurality of kinds of disaccharides derived from a glycosaminoglycan in a biological sample by adding a plurality of kinds of glycosaminoglycan-specific enzymes to the biological sample: and a second process for separating and analyzing the plurality of kinds of disaccharides by a liquid chromatography-mass spectrometry method, where a column used for liquid chromatography in the liquid chromatography-mass spectrometry method is a column packed with a stationary-phase support to which an amide group as a functional group is bound, or a column packed with a stationary-phase support to which an adamantyl group as a functional group is bound.

Abstract: When a liquid in the column is replaced by carbon dioxide in a supercritical state in the chromatograph, an operation of a first pump is controlled by a flow rate control unit, and the carbon dioxide in the supercritical state is supplied at a constant pressure. Moreover, when a flow rate of the carbon dioxide in the supercritical state reaches a predetermined flow rate thereafter, the flow rate control unit controls an operation of the first pump so that the carbon dioxide in the supercritical state is supplied at a constant flow rate.

Abstract: An analysis method includes: performing liquid chromatography using a mobile phase including an adsorption prevention agent for preventing adsorption of a sample including a compound having a phosphate group to metal; and performing mass spectrometry on an eluate of the liquid chromatography. The adsorption prevention agent includes an oxalic acid or a salt of the oxalic acid.

Abstract: When a liquid in the column is replaced by carbon dioxide in a supercritical state in the chromatograph, an operation of a first pump is controlled by a flow rate control unit, and the carbon dioxide in the supercritical state is supplied at a constant pressure. Moreover, when a flow rate of the carbon dioxide in the supercritical state reaches a predetermined flow rate thereafter, the flow rate control unit controls an operation of the first pump so that the carbon dioxide in the supercritical state is supplied at a constant flow rate.