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Compilation studies related to toxicological aspects and also biological monitoring and analysis methods for specific fungicides and, mainly, those that belong to the class of the dithiocarbamates (DTCs) have not been carried out at least in the last ten years. DTCs - dimethyldithiocarbamates, ethylenebisditiocarbamates, propylenebisditiocarbamates - are organosulfur compounds that form complexes due to the presence of different chemical elements, which bind strongly and inhibit enzymes that are essential to the functioning of the organism, causing a serious proven adverse effect on biological systems, such as alteration of thyroid hormones, teratogenesis and neurotoxicity. It is still evident, as shown by world data, that the growing consumption of fungicides has increasingly exposed the population in general and, in particular, workers who deal with these substances. There is a scarcity of studies in the literature discussing the toxicological and analytical aspects that are important for understanding the real effects of DTCs and monitoring human exposure to them. Therefore, the aim of this work was to expose, in a comprehensive way and through a narrative review, gaps in research related to the fungicides of the DTCs class, their metabolites, as well as the toxicological and analytical aspects involved. The review is divided into two parts: (1) Toxicological aspects, including toxicokinetics, toxicodynamics and toxidromes; and (2) Analytical Toxicology, which comprises biomarkers, sample preparation and identification/quantification methods.

Huntington’s disease (HD) is an inherited neurodegenerative disease characterized by motor, cognitive and behavioral deficits. Some evidence suggests that the endocannabinoid system participates in the pathophysiology of HD. We conducted a cross-sectional study comparing plasma levels of anandamide and 2-arachidonoylglycerol in manifest HD gene-expansion carriers (HDGEC) and healthy controls, finding no difference in endocannabinoid levels between the groups. Correlations between endocannabinoid levels and clinical scales (Mini-Mental State Examination, Hospital Anxiety and Depression Scale, Unified Huntington Disease Rating Scale) were non-significant. We found a significant association between body mass index and anandamide levels in healthy controls but not in HDGEC.

To assess endocannabinoid (anandamide, AEA; 2-arachidonoylglycerol, 2-AG) plasma levels in healthy volunteers and in volunteers with social anxiety disorder (SAD) after a single oral dose of ayahuasca or placebo.Post hoc analysis of endocannabinoid plasma levels (baseline, 90 and 240 min after drug intake) from two parallel-group, randomized, placebo-controlled trials. In Study 1, 20 healthy volunteers ingested ayahuasca (average 1.58 mg/ml dimethyltryptamine (DMT)) or placebo, and in Study 2, 17 volunteers with SAD received ayahuasca (average 0.680 mg/ml DMT) or placebo.A significant difference was observed in AEA concentrations in Study 2 after ayahuasca intake (ΧAlthough our findings suggest that ayahuasca could modulate AEA levels in SAD patients, the high interindividual variability in both trials and the small samples preclude definitive conclusions. More research with larger samples is needed to better understand the effects of ayahuasca and other hallucinogens in the endocannabinoid system.

It is known that drug abuse jeopardizes economic and social development. Toxicological analyses can guide prevention and treatment strategies in rehabilitation facilities. The current greatest challenge is finding easily adaptable and less costly sensitive methods that meet the principles of green chemistry. Hair, as a biological matrix, has several advantages, and its ability to detect consumption for longer periods keeping the matrix stable and unaltered stands out. This manuscript addresses the use of a miniaturized technique in an alternative matrix, by making use of a reduced amount of solvents to quantify amphetamines, aiming to guide prevention and treatment strategies in rehabilitation facilities.A Hollow Fiber Liquid-phase Microextraction (HF-LPME) technique for extracting amphetamines from hair samples with Gas Chromatography-Mass Spectrometry (CG-MS) was validated, adapted, and applied to ten samples from patients of a rehabilitation facility.The technique proved to be sensitive, accurate, precise, and not affected by interference from the biological matrix and the linear range for the analytes was 0.2 to 20 ng mgThe HF-LPME-GC-MS technique complied with the principles of green chemistry, and proved to be a sensitive technique, adaptable to the routine of common laboratories. Validation in the analysis phase with authentic samples, thus, showed that it can be an important tool for preventing and controlling drug addiction.

The main active compound of Cannabis sativa is Δ9-tetrahydrocannabinol, which is quickly transformed into 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (Δ9-THC-COOH) in the human body. This research aimed to validate an efficient, fast and low-cost technique for Δ9-THC-COOH analysis in urine with adaptations of existing analytical methods. The validation process was carried out in accordance with guidelines published by ANVISA and with international guidelines. The analyte was extracted by liquid-liquid extraction and identified/quantified by gas chromatography coupled to mass spectrometry. Linear curves ranges were from 5 to 300 ng mL-1 (r = 0.9993; y= 0.0269x – 0.0364). Intra and inter-day precision varied from 3.38 to 9.04% and accuracy was between 83 to 112.9%. The Δ9-THC-COOH remained stable after 15-30 days of storage at -20 °C (long-term test), after 5 freeze-thaw cycles and post-processing for up to 72 hours. The method is fast, low-cost, with detection limits and quantification below the cut-off (15 ng mL-1), which makes it useful and efficient for routine use at toxicology laboratories, for drug addiction and doping control, for forensic purposes and also for controlling the use of drugs of abuse by vehicle drivers.

This study aimed to investigate a miniaturized extraction methodology with analysis by GC-MS for simultaneous detection and quantification of cocaine (COC), benzoylecgonine (BZE) and cocaethylene (CE) in hair to monitor drug addicts. The process was done following the international guide of the Scientific Task Force on Forensic Toxicology. After sample extraction, derivatizing solution was added, clean-up was done by the Hollow Fiber Liquid Phase Microextraction (HF-LPME) and adapted to use the ultrasonic bath, a simple and easy-to-handle device. Isobutylchloroformate was first used as derivatization reagent to convert benzoylecgonine to isobutylbenzoylecgonine. Analytes quantification occurred within a linear range of 0.1 to 20 ng mg-1 for COC and 0.05 to 5 ng mg-1 for BZE and CE, with a correlation coefficient of r > 0.99. Limits of detection were 0.05; 0.03 and 0.03 ng mg-1, whereas limits of quantification were 0.1; 0.05 and 0.05 ng mg-1 for COC; BZE and CE, respectively. There was no matrix effect interference. Intra and inter-day precision and accuracy were acceptable according to international guidelines. The analytical method HF-LPME-GC-MS was successfully applied to 14 hair samples from patients admitted in drugs detoxification programs. All samples resulted positive for cocaine (0.80-> 20 ng mg-1) and benzoylecgonine (0.20-> 5 ng mg-1), 11 samples were positive for cocaethylene (0.10-> 0.60 ng mg-1).

BackgroundLevodopa-induced dyskinesias (LID) in Parkinson’s disease (PD) are frequent complications, and the endocannabinoid system has a role on its pathophysiology.ObjectiveTo test the hypothesis that the functioning of the endocannabinoid system would be altered in PD and in LID by measuring plasma and CSF levels of α-N-arachidonoylethanolamine (AEA) and 2-arachidonoyl-glycerol (2-AG) in patients with PD with and without LID and in healthy controls.MethodsBlood and CSF samples were collected from 20 healthy controls, 23 patients with PD without LID, and 24 patients with PD with LID. The levels of AEA and 2-AG were measured using a highly sensitive column switching ultrahigh-performance liquid chromatography-tandem mass spectrometry method.ResultsWhen pooled together, patients with PD had lower plasma and CSF levels of 2-AG and higher CSF levels of AEA compared to healthy controls (Mann-Whitney statistics = 303.0, p = 0.02). Patients with PD without LID had lower CSF levels of 2-AG (Kruskal-Wallis statistics = 7.76, p = 0.02) and higher CSF levels of AEA levels than healthy controls (Kruskal-Wallis statistics = 8.81, p = 0.01).ConclusionsThe findings suggest that the endocannabinoid system participates in the pathophysiology of PD symptoms, but its role in the pathophysiology of LID is still unclear.

A selective and sensitive method that uses automated in-tube solid-phase microextraction coupled to ultra-performance liquid chromatography–tandem mass spectrometry (in-tube SPME/UHPLC–MS/MS) was developed to determine cannabidiol (CBD) and Δ9-tetrahydrocannabinol (Δ9-THC) in plasma samples. A new dummy molecularly imprinted monolithic capillary (MIP monolith) for in-tube SPME was prepared by in situ polymerization in a fused silica capillary; hydrogenated cannabidiol was employed as dummy template. Fourier Transform Infrared Spectroscopy (FTIR) confirmed that the synthesis reagents were incorporated into the polymer chain. On the basis of the microscopy images (scanning electron microscopy – SEM and transmission electron microscopy – TEM), the MIP monolithic phase presented larger pores than the non-imprinted monolithic phase (NIP monolith), as well as a skeleton comprising clusters consisting of microspheres. By optimizing the polymerization conditions, the MIP monolith specifically recognized CBD and Δ9-THC. The MIP monolith had CBD and Δ9-THC sorption capacity of 148.05 and 44.49 ng cm−3, respectively. The capillary was reused over fifty times without significant changes in its extraction efficiency. For both CBD and Δ9-THC, in-tube SPME/UHPLC–MS/MS presented linear range from 10 to 300 ng mL−1, precision with coefficient of variation (CV) values ranging from 0.2% to 19.1% (LLOQ), and accuracy with relative standard deviation (RSD) values spanning from −9.3% to 19.6% (LLOQ). The developed method was successfully applied to determine cannabinoid levels in plasma samples from volunteer patients in treatment with CBD.

Os endocanabinóides são neurotransmissores derivados do ácido araquidônico que se ligam aos receptores canabinóides participando de diversas funções cerebrais, tais como memória, aprendizado e controle motor. Os principais endocanabinóides são a anandamida (AEA) e o 2-araquidonilglicerol (2-AG). A Doença de Parkinson (DP) é considerada a segunda patologia neurodegenerativa mais comum na população, sendo caracterizada pela redução da influência dopaminérgica. Indícios mostram um aumento de AEA e uma diminuição nos níveis de 2-AG em pacientes portadores da DP e em modelos animais induzidos ao parkinsonismo. O canabidiol (CBD) é um promissor fármaco para o tratamento da DP, pois acredita-se que apresenta um efeito neuroprotetor na degeneração de neurônios dopaminérgicos. Entretanto, o uso do ?9-Tetraidrocanabinol (?9-THC) não é indicado, pois pode apresentar efeitos psicotrópicos e dependência. A cromatografia líquida de alta eficiência acoplada à espectrometria de massas em tandem (HPLC-MS/MS) tem sido considerada a técnica analítica de referência para a determinação de endocanabinóides e canabinóides em amostras biológicas. A cromatografia líquida no modo column switching permite a automação das análises através da hifenação da etapa de preparo de amostras biológicas (pré-concentração dos analitos e remoção de grande parte dos componentes endógenos) com o sistema cromatográfico (separação cromatográfica e detecção). Neste contexto, dois métodos analíticos online utilizando o UHPLC-MS/MS no modo column switching foram desenvolvidos para determinação de (a) AEA e 2-AG; (b) CBD e ?9-THC em amostras biológicas de pacientes com DP. Os endocanabinóides foram determinados em amostras de plasma e de líquido cefalorraquidiano (LCR). O método UHPLC-MS/MS no modo column switching para determinação dos endocanabinóides com uma coluna de material de acesso restrito na primeira dimensão apresentou linearidade entre 0,100 (LIQ) a 6,00 ng mL-1 para AEA e 0,04 (LIQ) a 10,00 ng mL-1 para 2-AG nas amostras de plasma. Para as amostras de LCR a faixa linear foi de 0,45 (LIQ) a 9,00 ng mL-1 para AEA e 1,40 (LIQ) a 180 ng mL-1 para o 2-AG. Os valores de exatidão ficaram abaixo de 14,2% e de precisão abaixo de 11,1% (excluindo LIQ) para os dois analitos. Os métodos não apresentaram efeito residual e nem efeito matriz. Os analitos mostraram ser estáveis após ciclos de congelamento/descongelamento e no teste a curto e longo prazo. Estes métodos foram empregados para análise 70 amostras de plasma e 66 de LCR. Para a determinação (UHPLC-MS/MS no modo column switching) de CBD e ?9-THC em amostras de plasma foi sintetizada a fase molecularmente impressa (MIP) monolítica em capilar de sílica fundida (in situ). A síntese apresentou boa rentabilidade utilizando pequena massa da molécula molde (CBD reduzido). O método online, utilizando o capilar MIP na primeira dimensão, apresentou linearidade entre 10 e 300 ng mL-1 (CBD e ?9-THC). A precisão variou entre 0,2 e 10,3% para os dois analitos e a exatidão foi inferior a 4,4% (excluindo o LIQ). O efeito residual e o efeito matriz ficaram dentro dos parâmetros estabelecidos pela ANVISA. Por fim, o método foi aplicado satisfatoriamente na determinação de CBD e ?9-THC em amostras de plasma de pacientes em terapia com CBD Endocannabinoids are neurotransmitters derived from arachidonic acid; they bind to cannabinoid receptors and participate in various brain functions, such as memory, learning, and motor control. Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are the main endocannabinoids. Parkinson\'s disease (PD) is considered the second most common neurodegenerative pathology in the population, being characterized by reduced dopaminergic influence. Evidence shows an increase in AEA and a decrease in 2-AG levels in patients with PD and in animal models with induced parkinsonism. Cannabidiol (CBD) is a promising drug to treat PD: it is believed to have a neuroprotective effect on dopaminergic degeneration. However, the use of ?9- Tetrahydrocannabinol (?9-THC) is not indicated because it may lead to psychotropic effects and dependence. High-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) has been considered the benchmark analytical technique to determine endocannabinoids and cannabinoids in biological samples. Column switching allows analysis to be automated through hyphenation of the biological sample preparation stage (analytes pre-concentration and removal of most endogenous components) with the chromatographic system (chromatographic separation and detection). In this context, we have developed two online analytical methods based on UHPLC-MS/MS in the column switching mode to determine (a) AEA and 2-AG and (b) CBD and ?9-THC in biological samples from patients with PD. Endocannabinoids were determined in plasma and cerebrospinal fluid (CSF) samples. The UHPLC-MS/MS method in the column switching mode for determination of endocannabinoids with a column of restricted access material in the first dimension showed linearity between 0.100 (LIQ) and 6.00 ng mL-1 for AEA and 0.04 (LIQ) to 10.00 ng mL-1 for 2-AG in plasma samples. For CSF samples, the linear range was from 0.45 (LIQ) to 9.00 ng mL-1 for AEA and from 1.40 (LIQ) to 180 ng mL-1 for 2-AG. The accuracy values were below 14.2% and precision below 11.1% (excluding LIQ) for the two analytes. The methods had no residual effect or matrix effect. The analytes were stable after freeze/thaw cycles and in the short- and long-term test. These methods were used to analyze 70 plasma and 66 CSF samples. To determine CBD and ?9-THC in plasma samples (UHPLC-MS/MS in column switching mode), we synthesized a molecularly imprinted polymer (MIP) in the fused silica capillary (in situ). The synthesis showed good profitability because it required small mass of the template molecule (reduced CBD). The online method based on the MIP capillary in the first dimension showed linearity between 10 and 300 ng mL-1 (CBD and ?9-THC). Precision ranged from 0.2 to 10.3% for the two analytes and the accuracy was less than 4.4% (excluding LIQ). The residual effect and the matrix effect were within the parameters established by ANVISA. Finally, the method was satisfactorily applied to determine CBD and ?9-THC in plasma samples from patients on CBD therapy

This work proposes a flow injection analysis system for sulfaguanidine determination in pharmaceutical and food samples. The method was based on the reaction of sulfaguanidine with nitronium ion to...

This study reports a fast, sensitive, and selective column switching ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method to determine the endocannabinoids (eCBs), anandamide (AEA), and 2-arachidonoylglycerol (2-AG) in plasma samples. This bidimensional system used a restricted access media column (RP-8 ADS, 25 mm × 4 mm × 25 μM) in the first dimension and a core-shell Kinetex C18 (100 mm × 2, 1.7 mm × 1 μM) column in the second dimension, followed by detection in a mass spectrometer triple quadrupole (multiple reactions monitoring mode) operating in the positive mode. RP-8 ADS was used for trace enrichment of eCBs (reverse phase partitioning) and macromolecular matrix size exclusion; the core-shell column was used for the chromatographic separation. The column switching UHPLC-MS/MS method presented a linear range spanning from 0.1 ng mL−1 (LOQ) to 6 ng mL−1 for AEA and from 0.04 ng mL−1 (LOQ) to 10 ng mL−1 for 2-AG. Excluding the LLOQ values, the precision assays provided coefficients of variation lower than 8% and accuracy with relative standard error values lower than 14%. Neither carryover nor matrix effects were detected. This high-throughput column switching method compared to conventional methods is time saving as it involves fewer steps, consumes less solvent, and presents lower LLOQ. The column switching UHPLC-MS/MS method was successfully applied to determine AEA and 2-AG in plasma samples obtained from Alzheimer’s disease patients.

In-tube solid-phase microextraction (in-tube SPME) with capillary column as extraction device allows direct coupling to high performance liquid chromatography (HPLC) systems. This technique associates the advantages of on-line systems with the advantages of miniaturized systems. Since its development, in-tube SPME has been continuously improved. New couplings have also been evaluated on the basis of state-of-the-art HPLC instruments. Major achievements include the development of new capillary coatings to enhance the in-tube SPME performance (sorption capacity and selectivity). Innovative SPME fibers (fiber in-tube SPME) and capillary coatings based mainly on monolithic, nanoparticles, ionic liquids, carbon, and hybrid materials have been evaluated. This review provides an overview of the fundamental theory and current advances concerning in-tube SPME systems and highlights their main applications in environmental, clinical, and food analyses.

This work proposes a preconcentration method using an ion imprinted polymer (IIP) for determination of cadmium, in several samples, employing a mini-column filled with the polymer coupled into a flow injection analysis system with detection by thermospray flame furnace atomic absorption spectrometry (FIA-TS-FF-AAS). The polymer was synthesized via bulk using methacrylic acid and vinylimidazole as a functional monomer. For the FIA system initial assessment, the variables: pH, eluent concentration and buffer concentration were studied, employing a 23 full factorial design. To obtain the optimum values for each significant variable, a Doehlert matrix was employed. After the optimization conditions as: pH 5.8, eluent (HNO3) concentration of 0.48 mol L−1 and buffer concentration of 0.01 mol L−1, were adopted. The proposed method showed a linear response in the range of 0.081–10.0 μg L−1, limits detection and quantification of 0.024 and 0.081 μg L−1, respectively; preconcentration factor of 165, consumptive index of 0.06 mL, concentration efficiency 132 min−1, and frequency of readings equal to 26 readings h−1. The accuracy was checked by analysis of certified reference materials for trace metals and recovery tests. The obtained results were in agreement with 95% confidence level (t-test). The method was adequate to apply in samples of: jewelry (earrings) (2.38 ± 0.28 μg kg−1), black tea (1.09 ± 0.15 μg kg−1), green tea (3.85 ± 0.13 μg kg−1), cigarette tobacco (38.27 ± 0.22 μg kg−1), and hair (0.35 ± 0.02 μg kg−1).

This work describes the development and validation of an ultra-high performance liquid chromatography tandem mass spectrometry method that uses disposable pipette extraction (DPX-UHPLC-MS/MS) to determine the endocannabinoid anandamide (AEA) in cerebrospinal fluid samples (CSF). The DPX parameters sorption equilibrium time, sample volume, number of draw-eject cycles, washing solvent volume, and elution solvent volume were optimized by design of experiments (DOE) techniques. The simple DPX protocol proposed herein required a reduced amount of CSF sample and organic solvent. The DPX-UHPLC-MS/MS method presented linear range from 0.10 ng mL−1 (LLOQ) to 3.0 ng mL−1, inter- and intra-assay accuracy with EPR values varying from −8.2% to 9.6%, inter- and intra-assay precision with CV values ranging from 1.3% to 14.8% (except for the LLOQ), and no significant matrix effect. The innovative DPX-UHPLC-MS/MS method was successfully applied to determine AEA in CSF samples from Parkinson’s disease (PD) patients and should therefore be used in clinical studies.

Endocannabinoids (ECs) are endogenous lipid-based retrograde neurotransmitters that bind to cannabinoid receptors [cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2)]. Many ECs have been characterized; anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) are still considered the primary ECs signaling mediators. Dysregulation of ECs has been implicated in a wide range of pathologies, including neurodegenerative diseases. Understanding how ECs participate in neurological diseases is important to describe the pathology and to establish new treatments. Considering the physicochemical properties of ECs, liquid chromatography coupled to tandem mass spectrometry has become the reference method to determine these endogenous substances, in trace levels, in different biological samples. This review describes the recent advances in LC-MS/MS methods designed to determine ECs in complex biological matrixes. The advantages, limitations, selectivity, matrix effect, and sensitivity associated with each approach are emphasized. This article comprises three sections: (I) sample preparation techniques (conventional, microextraction, and online systems), (II) chromatographic methods (especially LC-MS/MS), and (III) relationship between ECs levels and neurodegenerative diseases.

This work presents an evaluation of iron and cadmium adsorption in sediment of the Furnas Hydroelectric Plant Reservatory located in Alfenas, Minas Gerais (Brazil). The metal determination was done employing a flow injection analysis (FIA) with an on-line filtering system. As detection techniques, flame atomic absorption spectrometry (FAAS) for iron and thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) for cadmium determinations were used. The developed methodology presented good limits of detection, being 190 μg L −1 for iron and 1.36 μg L −1 for cadmium, and high sampling frequency for both metals 144 and 60 readings h −1 for iron and cadmium, respectively. Both metals obey the Langmuir model, with maximum adsorptive capacity of 0⋅169 mg g −1 for iron and 7⋅991 mg g −1 for cadmium. For iron, a pseudo-first-order kinetic model was obtained with a theoretical Q e = 9⋅8355 mg g −1 (experimental Q e = 9⋅5432 mg g −1 ), while for cadmium, a pseudo-second-order kinetic model was obtained, with a theoretical Q e = 0.3123 mg g −1 (experimental Q e = 0⋅3052 mg g −1 ).

Many metals are toxic in human organism, as is the case of cadmium and lead. Therefore, the metal levels in food need to be controlled. In coffee, metals may present risks when they are extracted from the powder to be consumed as beverage. A flow injection analysis (FIA) system is proposed, with atomic absorption detection, to metal adsorption studies in coffee powder. Kinetic study, best isotherms and time, and mass influences were determined. They allowed analyzing the high lead and cadmium adsorption percentage in organic and conventional ground coffee. Metal adsorption occurs in multilayers, following Freundlich's model, and the kinetic model obeyed is the pseudo-second order. The cadmium adsorption suffered higher temperature influence, while the lead retention suffered higher mass influence. This study indicates that the majority of these toxic agents will be retained in the powder and will not be consumed by man, avoiding possible deleterious effects.