A method for analyzing spectra comprises identifying a set of sample peaks in a sample spectrum, where the sample peaks are associated with fragments of a sample, each having a sample fragment mass. A reference spectrum is selected with one or more reference peaks corresponding to fragments of a reference, each having a reference fragment mass. A mass difference can be determined between selected sample and reference peaks, and a group exchange can be selected based on the mass difference; e.g., where the group exchange represents a change in the sample or reference fragment masses associated with the selected peaks. The selected peaks can be shifted by the mass difference, and a fit value can be determined with respect to the reference spectrum. The fit value characterizes similarity between the respective sets of sample and reference peaks, responsive to the group exchange and corresponding peak shift.

The present invention provides a method for estimating the molecular complexity of a sample, for example to determine whether biotic or synthetic components are present in the sample. The method comprises the steps of (a) performing one of MS/MS, NMR or IR on a sample; (b) determining the unique peaks in the resulting spectrum; and (c) calculating the molecular assembly index of the sample based on the number of unique peaks in the spectrum.

Systems and methods are disclosed for identifying actual XIC peaks of compounds of interest from samples so that more accurate expected retention times and more accurate expected retention time windows can be calculated. In one system, an actual XIC peak is identified using standard samples. The ratio of the quantity of the compound of interest in any two different samples is known, so this ratios is compared to the intensities of the XIC peak calculated in the two samples to identify an actual XIC peak. In another system, an actual XIC peak is identified using information about other compounds of interest in a plurality of samples. It is known that the XIC peaks of compounds of interest in the same samples have a similar distribution of retention times across those samples, so the distributions of retention times of XIC peaks are compared to identify actual XIC peaks.

A measurement data processing device for graphically displaying measurement data for a plurality of target compounds and for performing quantitative determination for the target compounds is provided. The device includes a display section 7, a measurement data input receiver 43 for receiving an input of measurement data, a screen-display numerical data creator 44 for performing a previously determined process on the measurement data to calculate a quantitative value and create numerical data for screen display, a screen-display graphical data creator 46 for performing a previously determined process on the measurement data for the target compounds to create graphical data for screen display after the numerical data for screen display have been created for all target compounds, and a display processor 48 for displaying, in the display section, the numerical data for screen display and the graphical data for screen display in a form that depends on a user operation.

An analytical data analysis system (2) is a system that identifies composition substances contained in the sample to be analyzed and non-composition substances that are not the composition substance contained in the sample to be analyzed by comparing a standard chromatogram and an analysis target chromatogram. The analytical data analysis system (2) includes a non-composition substance information holding part (12) holding identification information and information on a peak expression position on a chromatogram of substances that may exist as the non-composition substance, a chromatogram synthesis part (16) configured to synthesize the information held in the non-composition substance information holding part with the standard chromatogram in order to describe identification information and the peak expression position of the substances that may exist as the non-composition substance on the standard chromatogram in which the composition substances of the standard sample are described, and a chromatogram display part (18) configured to display the analysis target chromatogram together with the standard chromatogram synthesized by the chromatogram synthesis part (16) on the display device (6).

A first analysis step of acquiring a three-dimensional chromatogram of at least one sample by executing, for the sample, first chromatography analysis using a photodiode array under a condition that a plurality of components contained in the sample can be separated from each other, and extracting spectrum data of each of a plurality of the components contained in the sample from the three-dimensional chromatogram of the sample, a second analysis step of executing second chromatography analysis using a photodiode array on another sample whose main component is the same as that of the sample under a condition that a three-dimensional chromatogram can be obtained in a shorter time than the first chromatography analysis to acquire a three-dimensional chromatogram of the another sample, and a peak separation step of acquiring peak separated data for the another sample in which peaks of a plurality of components contained in the another sample are separated from each other are included by applying peak separation processing based on the spectrum data extracted in the first analysis step to the three-dimensional chromatogram of the another sample acquired in the second analysis step.

The present specification relates to a method for analyzing deuterated benzene by gas chromatography, and preparing a deuterated compound using deuterated benzene selected based on the analyzed data.

One mode of a chromatograph mass spectrometer according to the present invention includes: a measurement unit (1) that includes a chromatograph unit (1A) and a mass spectrometry unit (1B) capable of performing MS/MS analysis, and collects chromatograph mass spectrometry data having three dimensions of time, m/z, and a signal intensity by repeatedly performing the MS/MS analysis by data independent analysis in the mass spectrometry unit on a sample containing a compound separated by the chromatograph unit; a component detection unit (42) that detects a compound and a component corresponding to a partial structure of the compound by obtaining MS/MS spectra of a bar graph presentation based on chromatograph mass spectrometry data over a predetermined m/z range for a target sample, estimating precursor ion peaks in each of the MS/MS spectra, and selecting peaks based on a predetermined standard regarding an m/z direction in each of the MS/MS spectra and a predetermined standard regarding a time direction for peaks that can be considered to be identical or an identical group on the MS/MS spectra; a narrowing unit (43, 44) that narrows down components to be analyzed by performing screening using prior information on the detected component; and a composition estimation unit (45) that, by using m/z information corresponding to a narrowed down component, estimate a composition or a chemical formula of the component.

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.

Disclosed are methods for improving compound detection and characterization. Methods for characterizing a sample are disclosed. The methods can include providing a sample to a liquid chromatography system capable of sample separation to generate sample components; analyzing sample components by multiplexed targeted selected ion monitoring (SIM) to generate an inclusion list; and performing iterative mass spectral data-dependent acquisition (DDA) from the inclusion list, to identify individual sample components thereby characterizing the sample. In one example, multiplexed targeted SIMs and iterative MS2 DDA acquisition is used to increase robust compound identification for cell culture medium analysis.