Areas of Study
Ambient Mass Spectrometry
Ambient Mass Spectrometry – AMS, is an area that encompasses numerous ionization techniques to form ions in a simple, fast and with minimal interference in the sample. AMS was developed since 2004 in order to enable the detection and quantification of chemical compounds present in complex samples directly from their natural state, without the use of separation or extraction methods. An important and widely used AMS technique is Paper Spray Ionization (PSI). PSI uses a pulp paper substrate that accommodates the sample and at the same time allows the ionization of analyts after the addition of solvent and the application of a high potential on the paper. In our laboratory we used PSI and developed new methods of environmental ionization, such as Fiber Spray Ionization (FSI), for detection and quantification of drugs of abuse, forensic toxicology, quality control of food and beverages, among other studies.
Figure 1. Detection illustration of several matrices by FT-ICR MS por J. F. A. Filho, N. A. Santos, K. B. Borges, V. Lacerda, F. S. Pelição, W. Romão, Rapid Commun. Mass Spectrom. 2020. Access on:< https://onlinelibrary.wiley.com/doi/abs/10.1002/rcm.8747>
Petroleomics
Development of processes and methodologies for the characterization of oil, derivatives and fractions. Research in this area is of paramount importance, since oil is still the most widely used energy matrix in the world. Among the examples of research lines in petroleum omics can be highlighted the characterization of paraffins, asphaltenes, hydrates and naphthenates, The formation of deposits in the oil industry is due to accumulations of these organic materials. Because it is a complex and expensive problem for the oil industry, through possible production stops, these species are widely studied. In addition, the composition of oil and its fractions varies according to origin, a fact that contributes to the complexity of this matrix and justifies the large number of studies in oil. Currently, there are research lines within petroleomics in the Laboratory of Petroleomics and Forensics: separation methodologies for isolation of tetraprotic naphthenic acids, known as NAEs; paraffin ionization studies, asphaltean sufficiency and petroleum asphalt cement (CAP) studies. All aim to achieve a detailed understanding of the composition, providing information such as molecular formulas (CcHhOoNn), isotopologist profile, classes of compounds, degree of unsaturation (DBE and van Krevelen diagram), degree of alkylation (carbon number distribution) and distribution of average mass molecular mass (Mw).
Figure 2. Illustration of analyses in petroleum and results obtained by processing.
Forensic Chemistry
Forensic chemistry is the branch of forensic sciences aimed at producing material evidence for justice, through the analysis of various substances in matrices, such as licit and illicit drugs, poisons, accelerants and fire residues, explosives, gunshot residues, fuels, paints, fibers, among others (Química Nova, 34, 1717, 2011). Within this line of research, we highlight works in Ballistics, Documentoscopy, Forensic Toxicology, fuel control and quality and food safety. The Laboratory of Petroleomics & Forensics makes use of mass spectrometry and different techniques of environmental ionization (ELI, PSI and others), digital image analysis (RGB) and also infrared vibrational spectroscopy and Raman.
Figure 3. Illustration of oil and fuel adulteration detection by microNIR and Chemometrics by Radigya M.Correia et al. Talanta 2018, 176, 26. Access on: http:// https://doi.org/10.1016/j.talanta.2017.07.094
Figure 4. Illustration of Analysis of Drugs of Abuse and Drugs by Near Infrared Portable Spectroscopy by Radigya M.Correia et al. Analytical Methods, 2018, 10(6), 593-603. Access on : https://doi.org/10.1039/C7AY02998E
Agribusiness and food chemistry
Food production in various segments defines Brazil as competitive, innovative and sustainable, being the country internationally recognized for being self-sufficient and one of the main exporters of food products. Among the areas are coffee and fruit growing. The quality of coffees and fruits (being the first major export product in Brazil and the state of Espírito Santo) is directly related to its chemical composition. The harvesting process, cultivation system, species and adulterationaffect the characteristics of the final product. For such discrimination, analytical techniques that present reliable, selective results and present little or no sample preparation are necessary. Thus, through the results by ESI-MS are built test protocols in order to monitor the quality control of coffees.
Figure 5. Study illustration on chemical profiles of Robusta and Arabica coffee by ESI (-) FT-ICR MS and ATR-FTIR por Radigya M.Correia et al. Analytical Methods, 2016,8, 7678-7688. Access on : https://doi.org/10.1039/C6AY02501C
Chemical imaging
Mass spectrometry imaging has the potential to provide new insights into the molecular analysis of various matrices, providing information on the spatial distribution of molecules present on the analyzed surface. The present research group has developed studies using mass spectrometry imaging in natural drugs Cannabis and Erythroxylum coca, Desing drugs, cross-sectionof pen traces (documentoscopy) and metabolites directly from animal tissues.
Figure 6. Illustration of imaging study by MALDI-FT-ICR MS.
