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The use of conductive polymers (CPs) as a substrate in ambient paper spray ionization was achieved under high DC voltage. Some pharmaceuticals, drugs of abuse, adulterants, metabolites, and impurities showed a signal that was higher in absolute intensity compared to that of uncoated papers. Surface characterization of the coated paper confirmed that the modified features on the paper surface were responsible for high electrical fields, signal stability, and reusability. The linearity and performance of CP-coated papers were demonstrated for a range of forensically relevant analytes, proving that CP-coated papers are an easy and cheap alternative for use in both qualitative and quantitative analyses.

Heavy oil fractions studies are of great importance for the oil industry, receiving particular attention in recent decades due to interest in obtaining compounds with higher added value derived from heavy oil fractions. Moreover, these studies also aim to offer solutions to problems caused by these fractions during all oil processing steps. Asphaltenes placed in n-methylpyrrolidone (NMP) produce two fractions with distinct characteristics, soluble and insoluble in NMP (called NS and NI, respectively). In previously studies it was suggested that the NI fraction presents low content of aromatic compounds, opening a new debate on the composition of asphaltene as is widely discussed in the literature. Here, we show the deep characterization of three set of asphaltenes fractions obtained in NMP using Fourier transform ion cyclotron resonance mass spectrometry coupled to positive and negative-ions mode electrospray ionization (ESI(±)-FT-ICR MS), Fourier transform infrared spectroscopy (FTIR), molecular fluorescence and p roton nuclear magnetic resonance ( 1 H NMR) spectroscopy. FTIR, 1 H NMR and molecular fluorescence demonstrated differences among asphaltene fractions studied, in which, NS fractions exhibited a more polar and aromatic character. On the other hand, NI fractions showed nonpolar profile, being proved by the presence of high amounts of alkyl and naphthenic hydrocarbons showing high abundance of alkyl and naphthenic hydrocarbon related compounds. ESI(±)FT-ICR MS data corroborate the FTIR, 1 H NMR and molecular fluorescence data, which show NS fractions with a high proportion of heteroatomic species and higher aromaticity (higher DBE values) compared with NI fractions.

Thin layer chromatography is a simple, easy and cheap technique widely used in Brazilian forensic laboratories, being a screening test for the separation and identification of illicit drugs, such as cocaine and its adulterants. Herein, paper chromatography using the Dragendorff reagent (revealing agent) was employed to analyze cocaine and its adulterants (levamisole, lidocaine, caffeine, and phenacetin). Positive results, i.e. visualization of the orange color, were only observed for cocaine, lidocaine and levamisole. Paper spray ionization mass spectrometry (PS-MS) was applied on revealed spots for the construction of a quantification model, for which some figures of merit were determined such as linearity, limit-of-detection (LOD), limit-of-quantification (LOQ) and accuracy. The results showed that PS-MS in positive-ion ionization mode, PS(+)-MS, is an efficient technique for direct analysis of the chromatographic spots on office-type paper revealed by the Dragendorff reagent. The method presented linearity greater than 0.98, and LODs of 6.51 μg mL−1 and 13.53 μg mL−1 for cocaine and levamisole, respectively, and 0.35 mg mL−1 for lidocaine. PS(+)MS was also applied to quantify cocaine in ten street crack samples, where there was no statistically significant difference between PS(+)MS and gas chromatography with flame ionization detection (GC-FID) data at a significance level of 5%.

With the advent of a new family of ionization techniques, ambient mass spectrometry (or ambient MS) was introduced as a simple way of generating ions in MS. Among them, the paper spray ionization (PS-MS) technique has demonstrated to be versatile to solve numerous problems in many areas of science. In this work, the PS-MS technique in the positive ionization mode (PS(+)-MS) was applied in two subareas of forensic chemistry: drugs of abuse and documentoscopy. In the first, the PS(+)MS technique was applied to obtain the chemical profiles of illicit drugs such as blotter papers containing 25I-NBOMe, extracts and leaves of natural cannabinoids (Δ9-tetrahydrocannabinol) and synthetic cannabinoids (naphthalen-1-yl-(1-butylindol-3-yl)methanone, (JWH-073); n-(adamantan-1-yl)-1-(4-fluorobutyl)-1H-indazole-3-carboxamide (5F-AKB48); 4-methyl-1-naphthyl-1-pentylindol-3-yl-methanone (JWH-122); 2-(2-methoxyphenyl)-1-(1-pentylindol-3-yl)ethanone (JWH-250); and 4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-210)) as well as to determine the authenticity in weight-loss herbal samples. Finally, an analytical method has been developed to quantify eight illicit drugs (3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-ethylamphetamine (MDEA), meta-chlorophenylpiperazine (m-CPP), methamphetamine (MA), cocaine, lysergic acid diethylamide (LSD), and dimethoxybromoamphetamine (DOB)) where their limit-of-detection ranged from 0.17 to 1 ppb, with linearity R2 > 0.99. The performance of the PS(+)-MS technique was also compared to other ionization sources: leaf spray mass spectrometry (LS-MS), and electrospray ionization mass spectrometry (ESI-MS). In the second part of this study, the PS(+)MS technique was successfully able to obtain the chemical profiles of different commercial blue pens. The relative intensity (RII372) of the methylene blue dye was monitored to discriminate crossings of traces, and to date questioned documents. The chemical profile of the second generation of Brazilian banknotes (R$, reais) was also explored. In general, the PS(+)-MS technique was proved to be an excellent analytical tool in forensic chemistry, acting like a “Swiss army knife”.

Cocaine is a stimulant drug of the central nervous system (CNS) extracted from the leaves of Erytroxylum coca. It is defined as a tropane alkaloid containing 1R-(exo,exo)-3-(benzoyloxy)-8-methyl-8-azabicyclo[3.2.1]octane-2-carboxylic acid methyl esther. However, despite its defined composition, a wide variety of chemical additives are present in cocaine found in the illicit market, such as benzocaine, lidocaine, caffeine, procaine and phenacetin. In this work, 512 cocaine samples seized by the Civil Police of Espirito Santo state (PC-ES, Brazil) were analyzed by gas chromatography mass spectrometry (GC-MS) allied to principal component analysis (PCA) in order to classify the samples as a function of seizure year (2008, 2009, 2010, 2011 and 2012) and location (metropolitan, north, south and central). The cocaine content (wt.%) and its adulterants were also estimated. Analyzing the samples seized between 2008 and 2011, three sample sets are clearly grouped according to the degree of adulteration with caffeine and lidocaine: 100-50 wt.% of cocaine; 50-20 wt.% of cocaine; and 20-80 wt.% of lidocaine and 60-80 wt.% of caffeine, simultaneously. The last group is formed by samples seized between 2008 and 2009, which proves the higher degree of adulteration during this period. In 2012, higher cocaine content was observed for the 191 analyzed samples than in samples from previous years. The PCA data also suggests that the metropolitan region samples had a higher degree of adulteration than the state countryside samples.

The use of new psychoactive substances (NPS) has been recognized worldwide at an alarming rate. Oral fluid collection is becoming more prevalent as a matrix for evaluating drug consumption. In this study, a specific, quick and non-invasive method for detection and quantitation of twenty-four synthetic cannabinoids and cathinone derivatives, including ten not previously reported NPS in oral fluid was performed. A quantitative method was developed on a liquid chromatography coupled to a triple quadrupole mass spectrometer system operated in dynamic multiple reaction monitoring (dMRM) mode using solid phase extraction (SPE) as pre-concentration step. Analytical separation of the target drugs was reached in a total elution time of 10 min. The developed method was validated according to the ASB standard 036. Overall bias and precision of the method were within ±20% for twenty-three compounds. All drugs showed acceptable linearity with R2 values greater than 0.98, and LLOQ values of 0.25 ng/mL and 1.0 ng/mL for selected NPS. The overall bias for a performed blind verification study was 7%. Our results demonstrate the method is suitable for quantifying NPS in oral fluid through solid phase extraction and analysis using LC–MS/MS.

Helicobacter pylori colonizes half of the World population and has been associated with gastric diseases including gastric cancer. In this scenario, Plectranthus barbatus is a wide-used medicinal plant in Brazil in the treatment of gastric injuries, however, no scientific report describe it against H. pylori. The aim of this study was to evaluate the ethyl acetate fraction (EAF) chemical profile from P. barbatus and its anti-H. pylori, immunomodulatory, antioxidant and cytotoxic activities. The substances identified by (-)-ESI-FT-ICR MS were plectrin, hydrolyzed abieatane, barbatusin, 3β-hydroxy-3-deoxibarbatusin, cyclobutatusin, luteolin, rosmarinic acid and coleoside B. The anti-H. pylori results presented a minimum inhibitory concentration (MIC) of 256 μg/mL and minimum bactericidal concentration (MBC) of 1024 μg/mL. Scanning electron microscopy evidenced H. pylori morphological changes in its surface induced by EAF. Molecular docking studies were conducted to investigate the binding mode of the proposed compounds at H. pylori Penicillin-Binding Protein active site. Antioxidant activities presented IC50 ranging from 26.64 ± 0.62–69.96 ± 1.25 μg/mL and the immunomodulatory activity was significant to IL-6 and NO with 28 % and 35 % of inhibition at 25 μg/mL. EAF showed significant cytotoxic activity with CI50 of 33.89 ± 0.32 μg/mL on gastric adenocarcinoma cells. These results indicate the potential of P. barbatus as candidate for H. pylori eradication and H. pylori induced related gastric disease prevention.

Made available in DSpace on 2018-11-29T06:20:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-03-01. Added 1 bitstream(s) on 2019-10-09T18:25:56Z : No. of bitstreams: 1 S0103-50532018000300639.pdf: 347454 bytes, checksum: 0e8bf43c43cd9b732cb0cc1b7921b7cd (MD5) FUNDECT (PRONEM) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Kardol Ind. Quimica Ltda. The synthesis of novel amino alcohol derivatives based on cardanol and glycerol were achieved in good yields and characterized by H-1 and C-13 NMR (nuclear magnetic resonance) and MS (mass spectrometry). In addition, we evaluated the in vitro antimicrobial activity against Gram-positive (Staphylococcus aureus, standard and clinical strains), Gram-negative (Escherichia coli) and M. tuberculosis bacterial strains. The bioassay results indicated that four compounds showed activity against S. aureus, including the clinical resistant strain, with MIC (minimum inhibitory concentration) ranging from 3.90 to 15.60 mu g mL(-1) and M. tuberculosis, with MIC90 (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) ranging from 3.18 to 7.36 mu g mL(-1). Univ Fed Mato Grosso Do Sul, Inst Quim INQUI, Av Senador Felinto Muller 1555, BR-79074460 Campo Grande, MS, Brazil Univ Fed Espirito Santo, Dept Quim, BR-29075910 Vitoria, ES, Brazil Univ Estadual Paulista, Fac Ciencias Farmaceut, BR-14801902 Araraquara, SP, Brazil Univ Fed Mato Grosso Do Sul, Inst Biociencias INBIO, Cidade Univ S-N,CP 549, BR-79070900 Campo Grande, MS, Brazil Univ Estadual Paulista, Fac Ciencias Farmaceut, BR-14801902 Araraquara, SP, Brazil FUNDECT (PRONEM): 054/12

Amaryllidaceae alkaloids are well-known isoquinolines which have demonstrated a wide range of biological activities such as antiviral, anticancer, acetylcholinesterase inhibition, antimalarial, among others. Mass spectrometry (MS) studies based on capillary gas chromatography (CGC), paper spray (PS), and leaf spray (LS) ionization were carried out for alkaloid investigation of the native Brazilian species Hippeastrum aulicum, along with nuclear magnetic resonance (NMR) techniques. Thirty-one alkaloids were identified including the new compound haemanthamine N-oxide. The results from PS- and LS-MS techniques were consistent with those observed in CGC-MS analysis. To the best of our knowledge, it is the first study combining NMR, CGC-MS and the ambient ionization-mass spectrometry (PS- and LS-MS) on Amaryllidaceae plants.

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.