3 research outputs found
Assessing the Effectiveness of Chemical Marker Extraction from Amazonian Plant Cupuassu (Theobroma grandiflorum) by PSI-HRMS/MS and LC-HRMS/MS.
Acknowledgments The authors acknowledge the institutional and financial support from the Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES) and the Brazilian Research Council (CNPq). Funding This research received no external funding.Peer reviewedPublisher PD
Multivariate classification techniques and mass spectrometry as a tool in the screening of patients with fibromyalgia
Abstract: Fibromyalgia is a rheumatological disorder that causes chronic pain and other symptomatic conditions such as depression and anxiety. Despite its relevance, the disease still presents a complex diagnosis where the doctor needs to have a correct clinical interpretation of the symptoms. In this context, it is valid to study tools that assist in the screening of this disease, using chemical work techniques such as mass spectroscopy. In this study, an analytical method is proposed to detect individuals with fibromyalgia (n = 20, 10 control samples and 10 samples with fibromyalgia) from blood plasma samples analyzed by mass spectrometry with paper spray ionization and subsequent multivariate classification of the spectral data (unsupervised and supervised), in addition to the treatment of selected variables with possible associations with metabolomics. Exploratory analysis with principal component analysis (PCA) and supervised analysis with successive projections algorithm with linear discriminant analysis (SPA-LDA) showed satisfactory results with 100% accuracy for sample prediction in both groups. This demonstrates that this combination of techniques can be used as a simple, reliable and fast tool in the development of clinical diagnosis of Fibromyalgia
Directly Mapping the Spatial Distribution of Organic Compounds on Mineral Rock Surfaces by DESI and LAESI Mass Spectrometry Imaging
Here, we present a new application of desorption electrospray
ionization
(DESI) and laser ablation electrospray ionization (LAESI) mass spectrometry
imaging to assess the spatial location of organic compounds, both
polar and nonpolar, directly from rock surfaces. Three carbonaceous
rocks collected from an aquatic environment and a berea sandstone
subjected to a small-scale oil recovery experiment were analyzed by
DESI and LAESI. No rock pretreatment was required before DESI and
LAESI analyses. DESI detected and spatially mapped several fatty acids
and a disaccharide on the surfaces of carbonaceous rocks, and various
nitrogenated and oxygenated compounds on the surfaces of berea sandstone.
In contrast, LAESI using a 3.4 Ī¼m infrared laser beam was able
to detect and map hydrocarbons on the surfaces of all rock samples.
Both techniques can be combined to analyze polar and nonpolar compounds.
DESI can be used first to detect polar compounds, as it does not destroy
the rock surface, and LAESI can then be used to analyze nonpolar analytes,
as it destroys a layer of the sample surface. Both techniques have
the potential to be used in several scientific areas involving rocks
and minerals, such as in the analysis of industry-derived contaminants
in aquatic sediments or in small-scale rockāfluid interaction
experiments