Improved Mass Accuracy and Precision for Multi-Attribute Methods Using a New Internally Calibrated High Resolution Orbitrap Mass Detector.

In the development of biotherapeutics, a thorough understanding of a molecule's product quality attributes (PQAs) and their effect on structure-function relationships and long-term stability is essential for ensuring the safety and efficacy of the product. First published in 2015, the multi-attribute method (MAM), based on LC-MS peptide mapping and automation principles, can be used to support biotherapeutic process and product development. The MAM provides simultaneous site-specific detection, identification, quantitation, and quality control monitoring of selected PQAs.

Targeted proteomic quantification on quadrupole-orbitrap mass spectrometer.

There is an immediate need for improved methods to systematically and precisely quantify large sets of peptides in complex biological samples. To date protein quantification in biological samples has been routinely performed on triple quadrupole instruments operated in selected reaction monitoring mode (SRM), and two major challenges remain. Firstly, the number of peptides to be included in one survey experiment needs to be increased to routinely reach several hundreds, and secondly, the degree of selectivity should be improved so as to reliably discriminate the targeted analytes from background interferences.

High precision measurement and fragmentation analysis for metabolite identification.

The degree of precision in measuring accurate masses in LC MS/MS-based metabolomics experiments is a determinant in the successful identification of the metabolites present in the original extract. Using the methods described here, complex broccoli extracts containing hundreds of small-molecule compounds (mass range 100-1,400 Da) can be profiled at resolutions up to 100,000 (full width half maximum, FWHM), useful for accurate and sensitive relative quantification experiments. Using external instrument calibration, analyte masses can be measured with high (sub-ppm to a maximum of 2 ppm) accuracy, leading to compound identifications based on elemental composition analysis.

Sensitive determination of prohibited drugs in dried blood spots (DBS) for doping controls by means of a benchtop quadrupole/Orbitrap mass spectrometer.

In the present study, a new type of mass spectrometer combining a quadrupole mass filter, a higher collision dissociation (HCD) cell and an Orbitrap detector, was evaluated for the analysis of dried blood spots (DBS) in doping controls. DBS analysis is characterized by the necessity to detect prohibited compounds in sub-nanogram-per-milliliter levels with high identification capacity. After extraction of DBS with an organic solvent and liquid chromatographic separation (using a regular C18-RP-analytical UHPLC-column) of target analytes, mass spectrometry is performed with a high-resolution full scan in positive and negative mode by means of electrospray ionisation.

lipID--a software tool for automated assignment of lipids in mass spectra.

A new software tool called lipID is reported, which supports the identification of glycerophospholipids, glycosphingolipids, fatty acids and small oligosaccharides in mass spectra. The user-extendable software is a Microsoft (MS) Excel Add-In developed using Visual Basic for Applications and is compatible with all Versions of MS Excel since MS Excel 97. It processes singly given mass-to-charge values as well as mass lists considering a number of user-defined options.

High-resolution extracted ion chromatography, a new tool for metabolomics and lipidomics using a second-generation orbitrap mass spectrometer.

Most analytical methods in metabolomics are based on one of two strategies. The first strategy is aimed at specifically analysing a limited number of known metabolites or compound classes. Alternatively, an unbiased approach can be used for profiling as many features as possible in a given metabolome without prior knowledge of the identity of these features.

Application of sustained off-resonance irradiation infrared multiphoton dissociation tandem mass spectrometry to the analysis of biomolecules.

A modified pulse sequence for infrared multiphoton dissociation (IRMPD) experiments on a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer in conjunction with sidekick trapping is presented. For IRMPD tandem mass spectrometry experiments gated trapping is normally applied. It ensures that the ions remain on-axis and, thus, cross the laser beam which is aligned on-axis in commercially available instruments.