The present invention is a data-processing device used for a chromatograph which continuously performs a series of analyses for components in each sample while sequentially introducing a plurality of samples into a column. The device includes: an input section configured to allow for input of information into a schedule table for a plurality of analyses, the schedule table describing an analysis condition including a combination of the values of a plurality of control parameters, the order of execution of the plurality of analyses, and information for identifying a sample to be subjected to each analysis; a chromatogram creating means configured to receive data sequentially collected during two or more analyses and create a joint chromatogram from the data if the two or more analyses have been continuously performed for the same sample according to the schedule table; and a display means configured to display the joint chromatogram.

[Problem to be solved] To provide a method for analyzing amino acids capable of easily analyzing D/L-amino acids in a sample with high reproducibility, particularly a simultaneous analytical method for L-amino acids and D-amino acids constituting a protein.

[Solution] A method for analyzing amino acids by liquid chromatography, in which a sample containing a plurality of kinds of amino acids is derivatized with a derivatization reagent, and the obtained derivatized sample is circulated on a column together with a mobile phase, wherein the mobile phase is composed of a plurality of mobile phases, and at least one mobile phase is a mixed solvent system, wherein two or more kinds of derivatized samples are prepared using two or more kinds of derivatization reagents, wherein different analytical conditions in which mixing ratio of the plurality of the mobile phases is changed with a passage of time are set for each kind of the derivatization reagent, and a solvent mixing ratio in the mobile phase being the mixed solvent system is set for the each kind of the derivatization reagent, and wherein the two or more kinds of derivatized samples are analyzed by automatically switching between the different analytical conditions and the solvent mixing ratio to separate and quantify derivatized L-amino acids and derivatized D-amino acids.

The invention pertains to the use of a specific biomarker of elastin degradation (desmosine) that measures the extent and progression of chronic obstructive pulmonary disease (COPD). In addition to potentially serving as a screening procedure for COPD, it provides a real-time measure of COPD drug efficacy and may therefore supersede the use of less sensitive tests such as pulmonary function studies and computed tomography. Equally important, the current invention constitutes a marked improvement for measuring desmosine in tissues and body fluids by greatly shortening the time for detection of this molecule in liquid chromatography-tandem mass spectrometry (LC-MS-MS) assays that are the gold standard for such measurements. Unlike previous methods, the invention allows for the use of LC-MS-MS without modification, so the method can be applied to any laboratory that uses this equipment for other measurements. This would include forensic facilities that need to determine if undiagnosed COPD played a role in the loss of life.

The present invention relates to a method for determining the origin of glutamic acid in a sample and, in a broader sense, relates to a method for determining the origin of an amino acid. The present invention makes it possible to measure the stable isotope ratio, with a considerably higher accuracy than that of conventional methods, by measuring the δ13C of glutamic acid (amino acid) by elemental analysis-stable isotope ratio mass spectrometry (EA-IRMS) and measuring the δ15N by gas chromatography-stable isotope ratio mass spectrometry (GC-IRMS). In addition, the present invention makes it possible to determine the origin of glutamic acid (amino acid) by comparing the stable isotope ratio of the glutamic acid (amino acid) whose origin is unclear with the stable isotope ratio of glutamic acid (amino acid) whose origin is clear.

The present invention provides a method in which a porous body having a monoclonal antibody to be measured immobilized in pores thereof is brought into contact with nanoparticles having a protease immobilized thereonto in a liquid to perform selective protease digestion of the monoclonal antibody and a peptide fragment obtained by the digestion is detected by liquid chromatography mass spectrometry (LC-MS), wherein the monoclonal antibody is digested with the protease in the presence of an antibody specifically binding to the monoclonal antibody or a target molecule of the monoclonal antibody.

In the present invention, among blood metabolites, amino acids, organic compounds and oxylipins that were statistically significantly differentiated from the control group, were selected from type 2 diabetes patients. Specifically, asparagine, aspartic acid, glutamic acid, cysteine, lysine, citric acid, and uric acid, and 12-oxo ETE, 15-oxo ETE, 9-oxo ODE, and 20-carboxy leukotriene B4, which are oxylipins, were confirmed to have cutoff values of AUC>0.7. In addition, the blood metabolites showed a significant difference between a DME patient group and a non-DME patient group, and thus were confirmed to be usable for accurate diagnosis of DME.

Embodiments of the present disclosure present methods, systems, and devices for extrachromosomal DNA extraction, and in some embodiments, isolation of DNA therefrom, and/or analysis of the extracted and/or isolated DNA, including, in some embodiments, ecDNA.

A pre-analysis treatment device usable for an amino acid, organic acid, and glucide includes an ion-exchange unit configured to load a test sample on a solid-phase cartridge S having a strong ion-exchange resin phase, to allow the strong ion-exchange resin phase to adsorb a predetermined organic compound, then supply a dehydration solvent to dehydrate the strong ion-exchange resin phase, and a derivatization unit configured to feed a predetermined amount of the derivatization reagent to the dehydrated strong ion-exchange resin phase to allow the derivatization reagent to retain for a predetermined time period, thereby trimethylsilylating the organic compound adsorbed on the strong ion-exchange resin phase, and simultaneously desorbing the trimethylsilylated organic compound from the strong ion-exchange resin phase, and then supply a push-out solvent to push the trimethylsilylated organic compound desorbed, out of the solid-phase cartridge S. The device enables at least one organic compound selected from amino acids, organic acids and glucides contained in a test sample to be derivatized and collected easily in a short period of time, and automation of the pre-analysis treatment.

Derivatives of an organic substance containing one or more groups selected from the group consisting of sulfanyl, selanyl and sulfino may be produced by reacting an organic substance containing one or more groups selected from the group consisting of sulfanyl, selanyl and sulfino with an olefin compound containing an ethylene structure having at least two electron-withdrawing groups except halogen atoms under an acidic condition to form a derivative of the organic substance

Disclosed herein are an amino acid analysis method and a liquid chromatographic apparatus for improving separation performance of threonine, serine, glycine, and alanine. The method of analyzing amino acids using the liquid chromatographic apparatus equipped with a cation exchange column includes a process for distributing a sample containing threonine, serine, glycine, and alanine as the amino acids, together with an eluent, to the cation exchange column to separate threonine, serine, glycine, and alanine, wherein a column temperature when separating threonine and serine is higher than a column temperature when separating glycine and alanine.