A mass isolation device selects a precursor ion of a sample that has been digested using a protease. A first fragmentation device fragments the precursor ion using collision-induced dissociation (CID), and the resulting product ions are analyzed using a mass analyzer producing a CID spectrum. A list of theoretical candidate glycopeptide sequences is determined from CID spectrum. The mass isolation device again selects the precursor ion of the sample. A second fragmentation device fragments the precursor ion using electron-based dissociation (ExD), and the resulting product ions are analyzed using the mass analyzer producing a CID spectrum. For each sequence of the list, the sequence is computationally fragmented, producing theoretical fragments, mass-to-charge ratio (m/z) values are calculated for the theoretical fragments, and the sequence is scored using c and z fragment matching rules. The highest scoring sequence is identified as a peptide sequence of a glycopeptide of the sample.

Methods for achieving complete sequence coverage of monoclonal antibodies by trypsin digestion and dual-column LC-MS system are provided. The disclosed method improves upon current techniques for standard peptide mapping.

A mass spectrometry system and a working method and an application thereof, and a sampling device. The mass spectrometry system includes an ion source, a sampling device and a mass spectrometer. The sampling device includes: a guide rail; a support adapted to move on the guide rail; a bearing member made from a hydrophobic material with two ends being fixed to the support; a plurality of containers for containing samples arranged on the support; a plurality of transport members made from a hydrophilic material and including a first portion provided on the bearing member and a second portion connected to the first portion and extending into each container; adjacent transport members being not in contact; and a drive module configured to drive the support to move on the guide rail such that a central axis of an exit port of the ion source passes through the first portion.

This disclosure relates to biomarkers for Age-Related Macular Degeneration (AMD) and methods of use thereof, e.g., methods of the use of biomarkers for determining that a subject has Age-related Macular Degeneration (AMD) or determining the stage of AMD in a subject.

A method, mass spectrometer and computer readable medium for acquiring mass spectral data in raw profile; detecting presence of compounds and relevant time window; performing multivariate statistical analysis of raw profile data in a time window to determine compounds; obtaining separation time profiles for detected compounds containing respective time locations in a time window; and computing pure mass spectra for compounds based on separation time profiles or time locations. A method, mass spectrometer and computer readable medium for acquiring mass spectral data in raw profile of a known and unknown sample; combining mass spectral scans for a sample into a single mass spectrum across a separation time window; performing multivariate statistical analysis of the acquired mass spectral data and computing a distance measure between the known and unknown sample; and using the distance measure as an indication for an unknown sample belonging to a known sample or sample group.

The present disclosure relates to a sensitive, multidimensional chromatography method for extraction, detection, and quantification of non-conjugated cytotoxic agents and associated linker molecules used in cysteine based antibody-drug-conjugate production.

A method for decomposing dermatan sulfate and heparan sulfate contained in a sample into a disaccharide, respectively, wherein the dermatan sulfate is decomposed into a disaccharide in which a uronic acid and an amino sugar are joined with an α-1,3 bond, and the heparan sulfate is decomposed into the disaccharide in which the uronic acid and the amino sugar are joined with the α-1,4 bond, and wherein, the dermatane sulfate is decomposed by heating in hydrogen chloride methanol solution containing 2,2-dimethoxypropane, at a temperature of 60 to 80° C., and for 20 to 100 minutes, and the heparan sulfate is decomposed by heating in hydrogen chloride methanol solution containing 2,2-dimethoxypropane, for 80 to 180 minutes, and at a temperature of 65 to 85° C.

The present invention provides assays and assay systems for use in spatially encoded biological assays. The invention provides an assay system comprising an assay capable of high levels of multiplexing where reagents are provided to a biological sample in defined spatial patterns; instrumentation capable of controlled delivery of reagents according to the spatial patterns; and a decoding scheme providing a readout that is digital in nature.

The present invention is a method for detecting a specific disease based on the result of a measurement in which the amount of a peptide serving as a biomarker contained in a biological sample is determined by using an LC-MS. A pretreatment process performed before the measurement using the LC-MS includes the steps of preparing a mixed sample solution by adding a stable isotope reagent and a trifluoroacetic acid to the biological sample, where the stable isotope reagent is prepared beforehand by labeling the peptide with a stable isotope; boiling the mixed sample solution; injecting the mixed sample solution after boiled into a solid-phase extraction column to make the peptide be retained in the solid-phase extraction column; and passing a water-soluble organic solvent through the solid-phase extraction column to elute the peptide retained in the solid-phase extraction column and collect the eluate.

Disclosed are methods and systems for the quantification of AngI and/or determination of plasma renin activity in a sample. The methods and systems disclosed herein can be useful for diagnosis of hypertension, aldosteronism and other abnormalities of the renin angiotensin aldosterone system (RAAS).