The invention relates to a method for the determination and visualization of the spatial distribution of tissue states of a tissue sample, wherein a mass/mobility map is acquired at each of a plurality of sample sites of the tissue sample, the signal heights at each sample site are determined at characteristic signal positions in the corresponding mass/mobility map, from which a tissue state for each sample site is calculated with the aid of a mathematical/statistical classification algorithm, and the spatial distribution of the tissue states calculated for the sample sites is represented graphically.

A method comprises measuring a first physico-chemical property of analyte ions so as to produce a data set, and identifying a first group of analyte ions within the data set. Analyte ions within the first group each have a value of an attribute that corresponds to a first value or that is within a first range of the attribute. The method further comprises selecting, from a plurality of different calibrations, a first calibration associated with the first value or first range of the attribute, and calibrating the measured first physico-chemical property of the first group of analyte ions using the first calibration.

A method of ion mobility and/or mass spectrometry is disclosed in which the ion mobility and/or mass to charge ratio of an ion is determined using an algorithm or relationship that relates the transit time or average ion velocity of the ion through an ion separation device in which one or more time-varying electric field is used to separate ions passing therethrough to one or more parameters for the device, the mass to charge ratio of the ion and the ion mobility of the ion.

A detector system comprises a first analytical stage configured to isolate ions from a sample, a field induced fragmentation stage configured to fragment the ions, a second analytical stage configured to characterize the ions, and at least one detector. The first analytical stage and the second analytical stage each comprise a differential mobility spectrometer. The field induced fragmentation stage comprises strips configured to create an electric field therebetween. In certain embodiments, the system further comprises a port configured between the first analytical stage and the field induced fragmentation stage, configured to introduce a reagent.

A method of mass spectrometry is disclosed comprising: a step (10) of analysing a reference compound in a first mass spectrometer and outputting mass spectral data in response thereto; a step (20) of analysing the reference compound in a second, different mass spectrometer and outputting mass spectral data in response thereto; and a step (30) of automatically adjusting an operational parameter, duty cycle (e.g. duty cycle of data acquisition), or acquired spectral data of at least one mass spectrometer such that, for the same (given) consumption of reference compound by the spectrometer, the statistical precision of quantification (the number of detected ions) and/or of mass measurement (the mass resolution) by the mass spectrometer is substantially the same as that of the other mass spectrometer. A similar method of ion mobility spectrometry is disclosed.

Disclosed is a novel means for accurate qualitative and quantitative analyses for each N-glycosylation site. The method of analyzing N-linked sugar chain(s) of glycoprotein according to the present invention comprises: treating a part of a glycopeptide-containing sample to be analyzed with endo-β-N-acetylglucosaminidases to cleave off sugar chains while leaving one GlcNAc of the chitobiose core on the Asn at the N-glycosylation site; subjecting the obtained sugar chain-cleaved sample to preliminary liquid chromatography/mass spectrometry; predicting the retention time of the glycopeptide of interest and the mass-to-charge ratio (m/z) of the precursor ion in main analysis based on the results of the preliminary liquid chromatography/mass spectrometry; and carrying out the main analysis. By this method, the binding sites and structures of N-linked sugar chains in a glycoprotein can be analyzed. By using the sugar chain-cleaved sample as an internal standard in the main analysis, quantitative analysis of sugar chains at each glycosylation site also becomes possible.

A use of an anthranilic acid derivative as a matrix for a MALDI Mass spectrometry, comprising: preparing a matrix compound represented by the following formula: ##STR00001## wherein X is selected from hydrogen and a hydroxyl group, and Y is selected from hydrogen, a methyl group or an acetyl group, provided that when X is hydrogen, Y is hydrogen or an acetyl group, and when X is a hydroxyl group, Y is a methyl group; applying the matrix compound and an analyte onto a sample holder; and analyzing the analyte by the MALDI mass spectrometer.

A known compound and at least one adduct, modified form, or peptide of the known compound are separated from a sample mixture and analyzed. An XIC is calculated for each of M product ions of the known compound and L product ions of the at least one adduct, modified form, or peptide. A first XIC peak group is calculated from the M XICs and a second XIC peak group is calculated from the L XICs using curve subtraction. Representative first and second XIC peaks are selected for the two XIC peak groups. The retention of the second XIC peak is shifted by an expected retention time difference found from a database. The retention time of the first XIC peak is verified as the retention time of the known compound if the difference of the retention times of the first and second XIC peaks is within a threshold.

A substance analyzer that includes, to enhance selectivity of substance analysis, the following: a heater that heats a medium for collecting a chemical substance adhering to a surface of an inspection object; a mass spectrometer that performs tandem mass spectrometry of vapor derived from the chemical substance heated and vaporized by the heater from the medium; and a control device that causes the mass spectrometer to perform, based on a temperature of the medium in the heater, tandem mass spectrometry for the chemical substance that is vaporized at the temperature of the medium using the vapor sent from the heater to the mass spectrometer.

Apparatus, methods and kits for detecting the contamination of a meat sample with another type of meat using parent-daughter ion transition monitoring that identifies peptides specific to a particular type of meat. The meat types detected can include pork, beef, lamb, chicken, duck and/or horse and one or more combinations thereof.