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Water pollution via natural and anthropogenic activities has become a global problem, which can lead to short and long-term impacts on humans' health and the ecosystems. Substantial amounts of individual or mixtures of organic pollutants move into the surface water via point and non-point source contamination. Some of these compounds are known to be toxic and difficult to remove from water sources, thus affecting their quality. Moreover, environmental regulations in high-income countries have become very strict for drinking water treatment over the past decades, especially regarding pesticides. This study aimed to evaluate the efficiency of different residential water treatments to remove 13 pesticides with distinct physicochemical characteristics from the drinking water. Nine water treatments were used: four membrane filters, an activated carbon filter, ultraviolet radiation, reverse osmosis, ion exchange resins, and ozonation. The trial was performed with tap water contaminated with an environmental concentration of 13 pesticides. According to the results, activated carbon and reverse osmosis were 100% efficient for pesticide removal, followed by ion exchange resins and ultraviolet radiation. Membrane filters, in general, showed low efficiency and should, therefore, not be used for this purpose.

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ABSTRACT: Chrysin flavonoid has been presented as having numerous and promising bioactive effects, such as antioxidant, anticonvulsant, antihypertensive, anti-inflammatory, antineoplastic, antihyperlipidemic, and antidepressant. However, one of the main challenges for advances in studies on the bioactivity of chrysin is its low bioavailability in humans. Thus, aiming to overcome this barrier, several studies have demonstrated the bioactive potential of capsules containing chrysin. The objective of this review was to present the main methodologies used for the encapsulation of chrysin, and its main biological effects demonstrated so far. Our intention is to offer ways to advancement of research in the area of flavonoid encapsulation. As for the encapsulation techniques, it was found that they are diverse, and the most recurrent encapsulating agents were PEG, PLGA polymers and their derivatives, in addition to other agents, such as PCL, albumin, lipids and chitosan.The bioactive effects of the capsules are also numerous, and anticarcinogenic effects are the most frequent, in addition to other effects such as antioxidant, antidiabetic, antimicrobial and neuroprotective. In conclusion, we verified a lack of use of green techniques for the encapsulation of chrysin, and the production of lipid-water emulsions and the dissolution of chrysin in ethanol seems to be alternatives in this regard. In addition, bioactive potential of these capsules can be evaluated in other experimental models, and should advance to clinical trials and application in food formulations.

RESUMO: O flavonoide crisina tem sido apresentado como tendo numerosos e promissores efeitos bioativos, como antioxidante, anticonvulsivante, anti-hipertensivo, anti-inflamatório, antineoplásico, anti-hiperlipidêmico e antidepressivo. No entanto, um dos principais desafios para o avanço dos estudos sobre a bioatividade da crisina é sua baixa biodisponibilidade em humanos. Assim, visando superar essa barreira, diversos estudos têm demonstrado o potencial bioativo de cápsulas contendo crisina. O objetivo desta revisão é apresentar as principais metodologias utilizadas para o encapsulamento da crisina e seus principais efeitos biológicos demonstrados até o momento. Nossa intenção é oferecer caminhos para o avanço das pesquisas na área de encapsulação de flavonoides. Quanto às técnicas de encapsulamento, verificou-se que são diversas, e os agentes encapsulantes mais recorrentes são os polímeros PEG, PLGA e seus derivados, além de outros agentes como PCL, albumina, lipídeos e quitosana. Os efeitos bioativos das cápsulas também são numerosos, sendo os efeitos anticarcinogênicos os mais frequentes, além de outros efeitos como antioxidante, antidiabético, antimicrobiano e neuroprotetor. Em conclusão, verificamos a falta de utilização de técnicas verdes para o encapsulamento de crisina, e a produção de emulsões lipídeo-água e dissolução da crisina em etanol parecem ser alternativas neste aspecto. Além disso, o potencial bioativo destas cápsulas pode ainda ser avaliado em outros modelos experimentais, e deve-se avançar para ensaios clínicos e aplicação em formulações alimentícias.

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The present study aimed to evaluate the Strata-X® sorbent, commonly used in cartridges, through analysis by high-performance liquid chromatography coupled with mass spectrometry. Due to the different physical-chemical characteristics of the compounds, different conditions of chromatography and mass analysis were necessary. The developed methods were validated in terms of selectivity, linear range, linearity (coefficient of determination, r2), the limit of detection (LOD), the limit of quantification (LOQ), accuracy (recovery, %), and precision (RSD, %). The results allowed us to select efficient extraction methods, using methanol acidified to pH 2 with formic acid, to elute the herbicides 2,4-D and dicamba in both sorbent materials. Besides, the Strata-X® sorbent was efficient in the sorption of analytes; thus, we indicate it for potential use in air sampling as an alternative to XAD-2.

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A miniaturized sample preparation method was developed and validated for the multiresidue determination of 97 pesticides in wine samples. The proposed extraction procedure is based on the QuEChERS acetate method with dispersive solid phase extraction (d-SPE) for the clean-up step. Ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) was used for determination. The extraction and clean-up steps were evaluated to obtain the best conditions for the selected pesticides. Miniaturization of the sample preparation step provided a reduction in the consumption of samples and chemicals. The method limit of quantification was between 10 and 20 µg L-1. Trueness results, obtained by recovery assays at the spike levels 10, 20, 50 and 100 µg L-1, ranged from 70 to 120% with precision in terms of relative standard deviations (RSD) ≤ 20%. The method was successfully applied for the analysis of wine samples and different pesticides were found at concentrations from 14 to 55 µg L-1.

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Sample preparation of complex matrices, like food samples, continues to be a challenge demanding great effort for improvements. In this study, a new technique named balls-in-tube matrix solid-phase dispersion (BiT-MSPD) is proposed based on a simplification of the conventional MSPD technique being all sample preparation performed directly in a closed extraction tube with the assistance of steel balls. An innovative method using BiT-MSPD was successfully established for the determination of 133 pesticide residues in apple, peach, pear and plum by ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS). Several sorbents were evaluated as solid support in different proportions with the sample. The homogenization step using mortar, glass rod or steel balls, with methanol and acetonitrile as extraction solvent, was evaluated. Vortex and ultrasound assisted extractions were also tested. Best results were obtained with C18, homogenization with steel balls, acetonitrile as solvent and ultrasound assisted extraction. Validation presented adequate trueness and precision results for the evaluated pesticides with recovery results ranging from 72 to 113% and RSD ≤ 17%. Practical limit of detection (LOD) and quantification (LOQ) for the compounds were 3 and 10 µg kg-1, respectively. The developed method proved to be easier and faster to perform than the MSPD, considering that extraction and clean-up are performed in the same tube without the need to transfer to cartridges, recipients or to use a separate clean-up step. The proposed BiT-MSPD technique was successfully applied to fruit samples and has great potential to be applied in other matrices, like cereals and meat, since the steel balls promote an efficient sample dispersion and extraction of pesticides. The BiT-MSPD permit a fully automation of the entire sample preparation step.

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In this study, the efficiency of a new fluorinated sorbent for dispersive solid-phase extraction (d-SPE) clean-up in extracts provided by the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) acetate method from tomato and sweet pepper samples was evaluated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Clean-up using d-SPE technique has been widely used associated with the QuEChERS method. The most commonly sorbents used in d-SPE are primary secondary amine (PSA), octadecylsilane (C18) and graphitized carbon black (GCB), which are indicated to remove sugars, fatty acids, pigments, among others. The performance of an alternative fluorinated sorbent was compared with PSA and C18 sorbents for representative pesticides and better results were obtained when the fluorinated sorbent was used. Validation presented acceptable results for trueness and precision, with method limit of detection between 0.9 and 1.8µgkg-1 and limit of quantification from 2.6 to 5.4µgkg-1. Most of the compounds presented low matrix effect. Results showed that the fluorinated sorbent contribute to the clean-up of the tomato extract and is an effective alternative, with lower costs and greater efficiency. Commercial tomato samples were analyzed using the proposed method and residues of dimethoate, tetraconazole and thiamethoxam were detected.

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Among calibration approaches for organic compounds determination in complex matrices, external calibration, based in solutions of the analytes in solvent or in blank matrix extracts, is the most applied approach. Although matrix matched calibration (MMC) can compensates the matrix effects, it does not compensate low recovery results. In this way, standard addition (SA) and procedural standard calibration (PSC) are usual alternatives, despite they generate more sample and/or matrix blanks consumption need, extra sample preparations and higher time and costs. Thus, the goal of this work was to establish a fast and efficient calibration approach, the diluted standard addition calibration (DSAC), based on successive dilutions of a spiked blank sample. In order to evaluate the proposed approach, solvent calibration (SC), MMC, PSC and DSAC were applied to evaluate recovery results of grape blank samples spiked with 66 pesticides. Samples were extracted with the acetate QuEChERS method and the compounds determined by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Results indicated that low recovery results for some pesticides were compensated by both PSC and DSAC approaches. Considering recoveries from 70 to 120% with RSD <20% as adequate, DSAC presented 83%, 98% and 100% of compounds meeting this criteria for the spiking levels 10, 50 and 100µgkg(-1), respectively. PSC presented same results (83%, 98% and 100%), better than those obtained by MMC (79%, 95% and 97%) and by SC (62%, 70% and 79%). The DSAC strategy showed to be suitable for calibration of multiresidue determination methods, producing adequate results in terms of trueness and is easier and faster to perform than other approaches.

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In this study, different extraction procedures based on the QuEChERS method were compared for the multiresidue determination of pesticides in orange juice by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). After choosing preliminary conditions, an experimental design was carried out with the variables C18, PSA, NaOH and CH3COONa to optimize the sample preparation step. The validation results of the validation were satisfactory, since the method presented recoveries between 70% and 118%, with RSD lower than 19% for spike levels between 10 and 100 µg L(-1). The method limit of detection (LOD) and limit of quantification (LOQ) ranged from 3.0 to 7.6 µg L(-1) and from 4.9 to 26 µg L(-1), respectively. The method developed was adequate for the determination of 74 pesticide residues in orange juice.

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