Potential of desorption electrospray ionization and paper spray ionization with high-resolution mass spectrometry for the screening of sports doping agents in urine.

In this work, desorption electrospray ionization and paper spray ionization both with high-resolution mass spectrometry (DESI-HRMS and PSI-HRMS) were explored for the fast and direct analysis of stimulants and diuretics in urine samples. The analysis was performed at a resolution of 70 000 FWHM (/ 200) using a quadrupole-Orbitrap mass spectrometer in full scan acquisition mode, detecting stimulants and diuretics in positive and negative ion modes, respectively. The most critical parameters affecting the desorption and ionization efficiencies of compounds were optimized, paying particular attention to the optimization of the spray solvent for PSI-HRMS analysis and to the selection of the DESI sample substrate.

Trace analysis of polystyrene microplastics in natural waters.

The development of quantitative and qualitative analytical methods to assess micro-plastics (MPLs) and nano-plastics (NPLs) content in the environment is a central issue for realistic risk assessment studies. However, the quantitative analysis continues being a critical issue, in particular for MPLs from 100 μm down to the nano-sized range in complex environmental samples. This paper evaluates the potential of mass spectrometry for the analysis of MPLs and NPLs.

Modified distribution in the polyphenolic profile of rosemary leaves induced by plant inoculation with an arbuscular mycorrhizal fungus.

Background: Rosemary forms an arbuscular mycorrhizal (AM) symbiosis with a group of soilborne fungi belonging to the phylum Glomeromycota, which can modify the plant metabolome responsible for the antioxidant capacity and other health beneficial properties of rosemary.

Results: The effect of inoculating rosemary plants with an AM fungus on their growth via their polyphenolic fingerprinting was evaluated after analyzing leaf extracts from non-inoculated and inoculated rosemary plants by ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Plant growth parameters indicated that mycorrhizal inoculation significantly increased plant height and biomass.

Desorption electrospray ionization-high resolution mass spectrometry for the screening of veterinary drugs in cross-contaminated feedstuffs.

In this study, a desorption electrospray ionization-high resolution mass spectrometry (DESI-HRMS) screening method was developed for fast identification of veterinary drugs in cross-contaminated feedstuffs. The reliable detection was performed working at high resolution (70,000 full width half maximum, FWHM) using an orbitrap mass analyzer. Among the optimized DESI parameters, the solvent (acetonitrile/water, 80:20, v/v) and the sample substrate (poly-tetrafluoroethylene, PTFE) were critical to obtain the best sensitivity.