Tag Archives: 2020

Phospholipidome of extra virgin olive oil: Development of a solid phase extraction protocol followed by liquid chromatography-high resolution mass spectrometry for its software-assisted identification

April 2020.

Antonelli M, Benedetti B, Cavaliere C, Cerrato A, Montone CM, Piovesana S, Lagana A, Capriotti AL.

Abstract

New insights in hemp chemical composition: a comprehensive polar lipidome characterization by combining solid phase enrichment, high-resolution mass spectrometry, and cheminformatics

January 2020.

Antonelli M, Benedetti B, Cannazza G, Cerrato A, Citti C, Montone CM, Piovesana

Abstract

Degradation studies of dimethachlor in soils and water by UHPLC-HRMS: putative elucidation of unknown metabolites

February 2020.

López-Ruiz R; Romero-González R; Ortega-Carrasco E; Martínez Vidal JL; Garrido Frenich A

Abstract

Background

The analytical control of the presence of dimethachlor and its metabolites in environmental samples, such as water and soils, is a main concern. Degradation of this pesticide has been evaluated in two types of soils and two different water conditions at two concentration levels. For that purpose, a new liquid chromatography-mass spectrometry method has been developed and putative identification of new metabolites has been performed. 

Results

An analytical method based on ultra-high-performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS) was developed to monitor the degradation of dimethachlor in environmental samples (water and soils). The degradation of dimethachlor in soils and groundwater samples has been monitored from 1 to 110 days after application of a plant protection product at two doses. Concentration of the parent compound slowly decreased in both matrices. 

DT50 values ranged from 40 to 70 days. Some metabolites were detected in the commercial product and in the samples one day after the application of the plant protection product. In addition, three new metabolites were putatively identified during dimethachlor degradation by untargeted analysis. 

Conclusions

In this study, the degradation of dimethachlor into its metabolites has been studied in soils and water, using a UHPLC-Orbitrap-MS validated method. A putative elucidation of new metabolites of dimethachlor has been carried out applying HRMS and software tools. Degradation results allowed for understanding the behavior of dimethachlor in soils and water and provided information regarding the possible risk of this pesticide and its metabolites to the ecosystem. 

LipostarMSI: Comprehensive, Vendor-Neutral Software for Visualization, Data Analysis, and Automated Molecular Identification in Mass Spectrometry Imaging

January 2020.

Tortorella S, Tiberi P, Bowman AP, Claes BSR, Ščupáková K, Heeren RMA, Ellis SR, Cruciani G. 

Abstract

Mass spectrometry imaging (MSI) visualizes molecular distributions throughout tissues but is blind to dynamic metabolic processes. Here, MSI with high mass resolution together with multiple stable isotope labelling provided spatial analyses of phosphatidylcholine (PC) metabolism in mouse lungs. 

Dysregulated surfactant metabolism is central to many respiratory diseases. Metabolism and turnover of therapeutic pulmonary surfactants were imaged from distributions of intact and metabolic products of an added tracer, universally 13C-labelled dipalmitoyl PC (U13C-DPPC). The parenchymal 

distributions of newly synthesized PC species were also imaged from incorporations of methyl-D9- choline. This dual labelling strategy demonstrated both lack of inhibition of endogenous PC synthesis by exogenous surfactant and location of acyl chain remodeling processes acting on the U13C-DPPClabelled surfactant, leading to formation of polyunsaturated PC lipids. This ability to visualize discrete metabolic events will greatly enhance our understanding of lipid metabolism in diverse tissues and has potential application to both clinical and experimental studies. 

A case study of the MassChemSite Reaction Tracking Workflow: Detecting and identifying byproducts during PROTAC synthesis

68th ASMS Conference on Mass Spectrometry and Allied Topics Reboot. Online. June 2020

Abstract

PROTACs are heterobifunctional small molecules composed of a ligand for a protein of interest (POI) and an E3 ligase recruiter connected through a linker.1 Instead of inhibiting the protein functions, PROTACs promote the formation of a ternary complex with POI and E3 ligase, inducing POI poly-ubiquitylation and its successive proteasomal-dependent degradation. 

This appealing technology has already attracted great attention from both academia and industry, and the optimization of PROTACs’ synthetic procedures is now needed. As an example, to automatically find byproducts formed during the synthesis of PROTAC, in this poster we will present the use of the Reaction Tracking workflow included in MassChemsite. This workflow is designed for untargeted multicomponent reactions.