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Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS) was used to examine the molecular composition of dissolved organic matter (DOM) from soils under different land use regimes and how the DOM composition in the catchment is reflected in adjacent streams. The study was carried out in a small area of the Schwingbach catchment, an anthropogenic-influenced landscape in central Germany. We investigated 30 different soil water samples from 4 sites and different depths (managed meadow (0–5 cm, 40–50 cm), deciduous forest (0–5 cm), mixed-coniferous forest (0–5 cm) and agricultural land (0–5 cm, 40–50 cm)) and 8 stream samples. 6194 molecular formulae and their magnitude-weighted parameters ((O/C) w , (H/C) w , (N/C) w , (AI-mod) w , (DBE/C) w , (DBE/O) w , (DBE-O) w , (C#) w , (MW) w ) were used to describe the molecular composition of the samples. The samples can be roughly divided in three groups. Group 1 contains samples from managed meadow 40–50 cm and stream water, which are characterized by high saturation compared to samples from group 2 including agricultural samples and samples from the surface meadow (0–5 cm), which held more nitrogen containing and aromatic compounds. Samples from both forested sites (group 3) are characterized by higher molecular weight and O/C ratio. Environmental parameters vary between sites and among these parameters pH and nitrate significantly affect chemical composition of DOM. Results indicate that most DOM in streams is of terrestrial origin. However, 120 molecular formulae were detected only in streams and not in any of the soil samples. These compounds share molecular formulae with peptides, unsaturated aliphatics and saturated FA-CHO/FA-CHOX. Compounds only found in soil samples are much more aromatic, have more double bonds and a much lower H/C ratio but higher oxygen content, which indicates the availability of fresh plant material and less microbial processed material compared to stream samples. [ABSTRACT FROM AUTHOR]

Graphical abstract: Display Omitted Highlights: [•] This paper is on the future Penning-trap facility MATS, the Technical Design Report of which was already approved in 2010. [•] It describes the current status on issues very important for MATS at FAIR. [•] It presents news on detection techniques and the progress achieved on different elements of the facility. [•] It presents a list of some possible candidates for the very first experiments at FAIR to underline the uniqueness of MATS. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) is involved in many important ecosystem processes. Ultrahigh resolution mass spectrometry has become a powerful technique in the chemical characterization of SOM, allowing assignment of elemental formulae for thousands of peaks resolved in a typical mass spectrum. We investigated how the addition of N, S, and P heteroatoms in the formula calculation stage of the mass spectra processing workflow affected the formula assignments of mass spectra peaks. Dissolved organic matter extracted from plant biomass and soil as well as the soil humic acid fraction was studied. We show that the addition of S and P into the molecular formula calculation increased peak assignments on average by 17.3 % and 10.7 %, respectively, over the assignments based on the CHON elements frequently reported by SOM researchers using ultrahigh resolution mass spectrometry. The organic matter chemical characteristics as represented by van Krevelen diagrams were appreciably affected by differences in the heteroatom pre-selection for the three organic matter samples investigated, especially so for the wheat-derived dissolved organic matter. These results show that inclusion of both S and P heteroatoms into the formula calculation step, which is not routinely done, is important to obtain a more chemically complete interpretation of the ultrahigh resolution mass spectra of SOM. [ABSTRACT FROM AUTHOR]

Management of the enormous amount of data produced during solution-phase hydrogen/deuterium exchange monitored by mass spectrometry has stimulated software analysis development. The proteolysis step of the experiment generates multiple peptide fragments, most of which overlap. Prior automated data reduction algorithms extract the deuteration level for individual peptides, but do not exploit the additional information arising from fragment overlap. Here, we describe an algorithm that determines discrete rate constant values to each of the amide hydrogens in overlapped fragments. By considering all of the overlapped peptide segments simultaneously, sequence resolution can be improved significantly, sometimes to the individual amino acid level. We have validated the method with simulated deuterium uptake data for seven overlapped fragments of a poly-Ala nonapeptide, and then applied it to extract rate constant values for the first 29 N-terminal amino acids of C22A FK506-binding protein. [ABSTRACT FROM AUTHOR]

Abstract: Combined with high and ultra high pressure liquid chromatography, mass spectrometry-based peptide and protein structure analysis requires high resolution and mass accuracy achievable within short ion detection time. Although Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) offers highest resolution and mass accuracy among all types of mass spectrometers, it is unacceptably slow for many applications in proteomics requiring on-line sample pre-fractionation. Multiple frequency detection promises to increase the speed of ion detection in FT-ICR MS without the loss of resolving power, but its application to peptide and, especially, protein analysis has been negligible. In this report, we show that double frequency detection in high field FT-ICR MS indeed allows faster acquisition of high resolution mass spectra of proteins. [Copyright &y& Elsevier]

Information about peptides and proteins in urine can be used to search for biomarkers of early stages of various diseases. The main technology currently used for identification of peptides and proteins is tandem mass spectrometry, in which peptides are identified by mass spectra of their fragmentation products. However, the presence of the fragmentation stage decreases sensitivity of analysis and increases its duration. We have developed a method for identification of human urinary proteins and peptides. This method based on the accurate mass and time tag (AMT) method does not use tandem mass spectrometry. The database of AMT tags containing more than 1381 AMT tags of peptides has been constructed. The software for database filling with AMT tags, normalizing the chromatograms, database application for identification of proteins and peptides, and their quantitative estimation has been developed. The new procedures for peptide identification by tandem mass spectra and the AMT tag database are proposed. The paper also lists novel proteins that have been identified in human urine for the first time. [ABSTRACT FROM AUTHOR]

The gas-phase reaction of triarylphosphine radical cations was examined by ion cyclotron resonance mass spectrometry. Triarylphosphine radical cations generated from triphenylphosphine, tris(m-tolyl)phosphine, and p-tolyldiphenylphosphine underwent bimolecular reaction with the parent phosphine that exists in large excess. On the other hand, radical cations generated from tris(p-toly)phosphine, o-tolyldiphenylphosphine, tris(o-toly)phosphine, and trimesitylphosphine gave totally different products. This is the first observation that a small substituent such as a methyl group on the aryl ligand results in dramatic change of the reactivity of triarylphosphine radical cations. [ABSTRACT FROM AUTHOR]

Analysis of samples of exhaled breath condensate (EBC) is a promising noninvasive method for the control of the status of the human respiratory system. In the present work, the proteome of the EBC samples received from a patient with lung dystrophy at different times before and after bilateral lung transplantation is analyzed by ion cyclotron resonance mass spectrometry. Qualitative protein composition of EBC samples obtained during the first month correlates with the clinical data on the acceptance of the transplanted lungs (allograft). Fifteen months after the lung surgery, the protein spectrum was similar to the normal composition of EBC proteins. This result agrees with the medical conclusion about normal lung functioning. The results suggest that the mass spectrometric monitoring of the protein spectra of EBC may be a tool for noninvasive pulmonological diagnostics. [ABSTRACT FROM AUTHOR]

Abstract: The KArlsruhe TRItium Neutrino experiment KATRIN aims at improving the upper limit of the mass of the electron antineutrino to about 0.2eV (90% c.l.) by investigating the -decay of tritium gas molecules . The experiment is currently under construction to start first data taking in 2012. One source of systematic uncertainties in the KATRIN experiment is the formation of ion clusters when tritium decays and decay products interact with residual tritium molecules. It is essential to monitor the abundances of these clusters since they have different final state energies than tritium ions. For this purpose, a prototype of a cylindrical Penning trap has been constructed and tested at the Max-Planck-Institute for Nuclear Physics in Heidelberg, which will be installed in the KATRIN beam line. This system employs the technique of Fourier-Transform Ion-Cyclotron-Resonance in order to measure the abundances of the different stored ion species. [Copyright &y& Elsevier]

• High throughput direct injection mass spectrometric method was developed. • Quantification and confirmation of ten quinolones was achieved in one hour. • Applicability was tested on both commercial and treated chicken samples. Many recent studies have shown high detection frequencies of quinolone antibiotics in poultry, as well as an increasing incidence of antimicrobial resistance. The main purpose of this project was to develop a fast and reliable analytical method for the detection of quinolones in poultry meat. In order to develop a rapid quantitative confirmation method, ion cyclotron resonance mass spectrometer was used. First, the sample preparation procedure was simplified by reducing the procedure to extraction and freezing out steps. Second, the chromatographic separation step was excluded and mass spectrometric parameters were optimised. Third, the method was validated by fortifying a blank matrix at four levels (0.5, 1, 1.5, and 2 times the maximum residue limit (MRL) or level of interest in those cases when no MRL was established). As a result, the overall analysis time was reduced to less than an hour. The validation study revealed that the method is capable of detection and confirmation of ten quinolone compounds in poultry above the detection capability (CCβ) of the procedure. Finally, the developed method was applied to 19 commercially available chicken meat samples. None of the samples contained quinolones above the limit of quantification (LOQ) of the method. Analysis of treated chickens revealed that the developed method is suitable for the determination of ciprofloxacin and enrofloxacin. The developed method could be one of the fastest quantitative confirmatory methods for the analysis of quinolones available so far. [ABSTRACT FROM AUTHOR]