Hydrocarbons present in saturated fractions of crude oils can be assessed by atmospheric pressure chemical ionization (APCI) using small hydrocarbons as ionizing reagents in a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS). In this work, five paraffin standards of different average molar mass distributions (Mw) were easily ionized by APCI(+)FT-ICR MS using isooctane as the reagent gas. Data of Mw, carbon number and double bond equivalent (DBE) distributions corresponding to linear and cyclic hydrocarbons (HCs) were compared to results obtained from analysis of high temperature gas chromatography with a flame ionization detector (HTGC-FID), comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC×GC-MS) and 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. APCI(+)FT-ICR MS data showed good agreement with those of analytical techniques. Furthermore, the ability of APCI(+) to assess n-paraffin, even in blends with polyaromatic hydrocarbon molecules such as coronene (Mw = 301 Da) at concentrations from 2.5 to 25 µg mL-1, was demonstrated. The typical MS paraffin profile (containing repeating mass units of 14 Da) was clearly confirmed, being totally suppressed when a concentration of 25 µg mL-1 of coronene was used. This phenomenon was also evidenced in one of two saturated fractions produced using saturates, aromatics and polar (SAP) compound fractionation methodology.

The Cannabis sativa L. plant has a complex chemical composition, containing various chemical compounds such as terpenes, sugars, hydrocarbons, steroids, flavonoids, and amino acids. Few works have attempted to identify the constitutional isomers of cannabinoids that are found in the plant. The present study reported the analysis of seven cannabinoid standards: five neutral and two acidic, as well as Cannabis products (hashish and marijuana) and parts of the Cannabis plant (flower and leaf) using mono-dimensional gas chromatography coupled with mass spectrometry (GC-MS) and two-dimensional gas chromatography coupled with quadrupole MS (GC × GC-QMS), ultra performance liquid chromatography coupled with electrospray ionization-quadrupole-time of flight (UPLC-ESI-QTOF)-MS and UPLC-ESI-travelling wave ion mobility (TWIM)-MS. The results of GC-MS demonstrated close retention times (∆tR = 1.303 min) in separation of the five cannabinoid standards, whereas GC × GC-QMS provided a substantially better identification and distinction of constitutional isomers of cannabinoids, where a total of 11 cannabinoids were identified in the hashish sample. UPLC-QTOF-MS and UPLC-TWIM-MS data obtained complete chemical information, in which ESI(+) revealed the presence of seven constitutional isomers of ∆9-tetrahydrocannabinol (∆9-THC), whereas ESI(-) proved the presence of four isomers of ∆9-tetrahydrocannabinolic acid A (∆9-THCA A).

Competitive adaptive reweighted sampling-partial least squares (CARS-PLS) and negative-ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(-) FT-ICR MS) data were adopted to assess the total acid number (TAN) of crude oil distillation cuts. Two crude oil samples and 24 derivatives with TAN ranging from 0.20 to 0.39 mg of KOH g-1 were investigated. The multivariate calibration PLS model was built with 18 calibration samples and tested with 8 validation samples. CARS-PLS reduced the number of variables from 1610 to only 4, allowing the identification of molecular formulas that are truly related to the TAN. The root mean square error of prediction (RMSEP) obtained was 0.01 mg of KOH g-1, which is lower than the error when using all variables (0.03 mg of KOH g-1). Finally, it was observed that the N and O2 compound classes are the most important classes for providing a better correlation between ESI(-) FT-ICR mass spectra and TAN values.

ABSTRACT Seaweeds are related to anti-inflammatory, anti-bacterial and anti-noceptive effects. This work aimed to verify the potential of seaweed Padina gymnospora (Kützing) Sonder 1871 to improve wound healing in vitro. P. gymnospora was collected at a bethonic area in Espirito Santo. Methanolic extract of P. gymnospora was obtained by percolation. To determine cytotoxicity, colorimetric MTT tests were performed against normal fibroblasts (L929), macrophages (RAW 264.7) and human ovarian carcinoma (OVCAR-3) cell lines using concentration range of 12–110 µg ml-1. To evaluate in vitro wound healing, monolayer of fibroblasts L929 was seeded and artificial wounded. Cell proliferation was blocked by 5 µg ml-1 Mytomycin C. Nitric oxide inhibition was quantified with Raw 264.7 by Griess reaction. Minimal inhibitory concentration (MIC) against Staphylococcus aureus was determined. Eletrospray ionization with Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR MS) was applied to detail composition of P. gymnospora methanolic extract. No cytotoxic effect in all cell lines was detected until the maximum concentration of 110 µg ml-1. P. gymnospora promoted significantly migration at the concentration of 25 µg ml-1 (p < 0.05). A prominent inhibition of nitric oxide formation was achieved in a concentration of 20 µg ml-1 of methanolic extract of P. gymnospora (62.06 ± 1.20%). Antibacterial activity against S. aureus could be demonstrated with MIC of 500 µg ml-1. ESI-FT-ICR MS analysis indicated eleven molecules between then, linolenic, oleic and linoleic acid. P. gymnospora favored wound repair in vitro what could be related to its fatty acid composition. In addition, its antimicrobial effect, and NO inhibition activity contribute for a new approach of P. gymnospora as a promise natural product for treatment of cutaneous wound.

Drug trafficking and the introduction of new drugs onto the illicit market are one of the main challenges of the forensic community. In this study, the chemical profile of a new designer drug, 2-(4-iodine-2,5-dimethoxyphenyl)-n-[(2-methoxyphenyl)methyl]etamine or 25I-NBOMe was explored using thin layer chromatography (TLC), ultraviolet-visible spectrophotometry (UV-Vis), attenuated total reflection with Fourier transform infrared spectroscopy(ATR-FTIR), gas chromatography mass spectrometry (GC-MS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR MS). First, the TLC technique was effective for identifying spots related to 25C-, 25B- and 25I-NBOMe compounds, all with the same retention factor, Rf ≈ 0.50. No spot was detected for 2,5-dimethoxy-4-bromoamphetamine, 2,5-Dimethoxy-4-chloroamphetamine or lysergic acid diethylamide compounds. ATR-FTIR preserved the physical-chemical properties of the material, whereas GC-MS and ESI-MS showed better analytical selectivity. ESI(+)FT-ICR MS was used to identify the exact mass (m/z428.1706 for the [M + H]+ ion), molecular formula (M = C18H22INO3), degree of unsaturation (DBE = 8) and the chemical structure (from collision induced dissociation, CID, experiments) of the 25I-NBOMe compound. Furthermore, the ATR-FTIR and CID results suggested the presence of isomers, where a second structure is proposed as an isomer of the 25I-NBOMe molecule.