A method of determining an identity of a first analyte in a sample is described that includes passing the first analyte through a chromatographic column and detecting a signal curve of the first analyte by a chromatographic detector, wherein the signal curve includes a peak profile of the first analyte. The peak profile is defined by a plurality of measured data points configured to plot onto a signal coordinate system. The method further includes normalizing the peak profile of the first analyte to form a normalized peak profile, wherein the normalized peak profile includes scaling the plurality of measured data points, and wherein the normalized peak profile is defined by a plurality of normalized data points configured to plot onto a normalized coordinate system, and comparing the normalized peak profile of the first analyte with a normalized peak profile of a second analyte.

A method for determining a quantity of an analyte in a liquid sample, comprises: adding a known quantity of an internal standard comprising an isotopically labeled version of the analyte to the sample; (b) providing a continuous stream of the sample having the internal standard to an inlet of a Liquid Chromatography Mass Spectrometry (LCMS) system; and repeatedly performing the steps of: performing a data-independent analysis of the precursor ion species using a mass analyzer, whereby mass spectra of a plurality of fragment-ion species are acquired; calculating one or more degree-of-matching scores that relate to either a number of ions of the internal standard that overlap between results of the data-independent analysis and tabulated mass spectral data of the internal standard; and performing quantitative tandem mass spectrometric analyses of the internal standard and the analyte if each of the degree-of-matching scores meets a respective degree-of-matching condition.

An analysis method for data generated by at least two parameters is provided. The method includes a comparison step of making a comparison between a data shape of a target component in a measurement sample and a standard shape acquired in advance, and a step of identifying the target component in the measurement sample based on the comparison.

A peak-waveform conversion processor detects a peak in a profile spectrum created based on data obtained at each measurement point in a sample's measurement area, and acquires a rod-like peak by performing centroid conversion processing on a waveform of the peak having a mountain shape. When an operator specifies a target compound to be observed, a mass difference calculation unit calculates a mass difference between a precise m/z of the target compound and an m/z of a rod-like peak at a position close to the precise m/z for each measurement point. A mass difference image creator creates an image showing a distribution of mass differences based on the calculated mass differences. A mass difference related information calculation unit acquires an index value such as an average value of a plurality of mass differences for each mass difference image, and creates a graph showing a frequency distribution of the mass differences.

A peak-waveform conversion processor detects a peak in a profile spectrum created based on data obtained in each micro area in a measurement area, and acquires a rod-like peak by performing centroid conversion processing on a waveform of the peak in a mountain shape. When receiving a precise m/z value Ma of a target compound and an allowable range ΔM of m/z, an image creator determines whether or not there is a rod-like peak in a range defined by “Ma±ΔM”, for each micro area. When there is a rod-like peak, a height value of the rod-like peak is defined as the signal intensity value of the target compound in the micro area. In contrast, when there is no rod-like peak in the range defined by “Ma±ΔM”, the signal intensity value of the target compound in the micro area is set to zero.

A peak analyzing method for separating overlapping peaks observed in a second signal waveform representing a relationship between a second parameter and a signal intensity into a plurality of individual peaks originating from different factors based on signal patterns observed in a dimension of a first parameter, the method including at least: performing singular value decomposition on an input matrix expressing three-dimensional data to be processed; estimating characteristic orientations within a space spanned by a plurality of basis vectors by performing a geometric analysis on a trajectory defined by a plurality of weighting vectors in an SVD projection space whose number of dimensions is equal to a lowered rank given by a singular value decomposition process; and deconvoluting signal waveforms in a first matrix of a dimension of the first parameter by a transformation matrix.

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.

Provided is a mass spectrometer including: a prediction equation storage section 34 configured to store a plurality of prediction equations which respectively correspond to different kinds of isotopic ions originating from a compound, each prediction equation expressing a relationship between m/z of a monoisotopic ion of the compound and a ratio between the signal intensity at the monoisotopic ion of the compound and the signal intensity of an isotopic ion in a mass spectrum; a measurement section 1 configured to perform chromatograph mass spectrometry on a sample to collect data; a predicted mass spectrum creation section 33 configured to calculate a predicted value of the signal intensity ratio related to each isotopic ion, by applying, in the prediction equations, m/z information corresponding to a peak observed on a measured mass spectrum and information of a given charge state of the ion, and to create a predicted mass spectrum based on the predicted values; and a mass spectrum evaluation section 33 configured to evaluate the possibility that a plurality of peaks in the measured mass spectrum are peaks originating from one compound, by comparing the predicted mass spectrum and the measured mass spectrum.

A Liquid Chromatography Mass Spectrometry system comprises: a chromatograph; a mass spectrometer configured to ionize separated fractions of a sample received from the chromatograph; and a programmable processor operable to repeatedly execute the steps of: (i) causing the mass spectrometer to perform a data-independent analysis of the precursor ion species using a mass analyzer of the mass spectrometer; (ii) calculating one or more degree-of-matching scores that relate to detection of an internal standard; and (iii) if each of the degree-of-matching scores meets a respective degree-of-matching condition, performing a quantitative tandem mass spectrometric analyses of both the internal standard and the analyte; the programmable processor further operable to calculate a quantity of the analyte in the sample by comparison between intensities of one or more mass spectral signals generated by the quantitative tandem mass spectrometric analyses of the analyte and the internal standard.

An automated method of monitoring a state of an analyzer is provided including a mass spectrometer (MS) with an electrospray ionization (ESI) source coupled to a liquid chromatography (LC) stream, including monitoring an electrospray ionization current of the ESI source and identifying a condition of multiple conditions of the analyzer based on the monitored ionization current of the ESI source, one of the conditions being a presence of a dead volume in a liquid chromatography stream of the analyzer downstream of an LC column of the LC stream.