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1.
Brain Behav Immun ; 119: 301-316, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38608740

RESUMO

Maternal obesity is associated with an increased risk of psychiatric disorders such as anxiety, depression, schizophrenia and autism spectrum disorder in the offspring. While numerous studies focus on preventive measures targeting the mothers, only a limited number provide practical approaches for addressing the damages once they are already established. We have recently demonstrated the interplay between maternal obesity and treatment with cannabidiol (CBD) on hypothalamic inflammation and metabolic disturbances, however, little is known about this relationship on behavioral manifestations and neurochemical imbalances in other brain regions. Therefore, here we tested whether CBD treatment could mitigate anxiety-like and social behavioral alterations, as well as neurochemical disruptions in both male and female offspring of obese dams. Female Wistar rats were fed a cafeteria diet for 12 weeks prior to mating, and during gestation and lactation. Offspring received CBD (50 mg/kg) from weaning for 3 weeks. Behavioral tests assessed anxiety-like manifestations and social behavior, while neuroinflammatory and neurochemical markers were evaluated in the prefrontal cortex (PFC) and hippocampus. CBD treatment attenuated maternal obesity-induced anxiety-like and social behavioral alterations, followed by rescuing effects on imbalanced neurotransmitter and endocannabinoid concentrations and altered expression of glial markers, CB1, oxytocin and dopamine receptors, with important differences between sexes. Overall, the findings of this study provide insight into the signaling pathways for the therapeutic benefits of CBD on neuroinflammation and neurochemical imbalances caused by perinatal maternal obesity in the PFC and the hippocampus, which translates into the behavioral manifestations, highlighting the sexual dimorphism encompassing both the transgenerational effect of obesity and the endocannabinoid system.


Assuntos
Ansiedade , Comportamento Animal , Canabidiol , Hipocampo , Obesidade Materna , Córtex Pré-Frontal , Efeitos Tardios da Exposição Pré-Natal , Ratos Wistar , Animais , Feminino , Canabidiol/farmacologia , Gravidez , Ratos , Masculino , Obesidade Materna/metabolismo , Ansiedade/metabolismo , Ansiedade/tratamento farmacológico , Ansiedade/etiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Doenças Neuroinflamatórias/metabolismo , Doenças Neuroinflamatórias/tratamento farmacológico , Comportamento Social , Obesidade/metabolismo , Endocanabinoides/metabolismo
2.
Anal Bioanal Chem ; 415(18): 3671-3681, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36598538

RESUMO

The proposal of high-throughput platforms in microextraction-based approaches is important to offer sustainable and efficient tools in analytical chemistry. Particularly, automated configurations exhibit enormous potential because they provide accurate and precise results in addition to less analyst intervention. Recently, significant achievements have been obtained in proposing affordable platforms for microextraction techniques capable of being integrated with different analytical instrumentations. Considering the evolution of these approaches, this article describes innovative high-throughput platforms that have recently been proposed for the analysis of varied matrices, with special attention to laboratory-made devices. Additionally, some challenges, opportunities, and trends regarding these experimental workflows are pointed out.


Assuntos
Microextração em Fase Sólida , Microextração em Fase Sólida/métodos
3.
Biomed Chromatogr ; 37(4): e5586, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683129

RESUMO

Vancomycin is used as an antimicrobial agent for the treatment of severe gram-positive infections. The importance of therapeutic monitoring of antimicrobials has led to the development of more specific sample preparation techniques capable of identifying with accuracy the concentration of this substance in the organism. An aliquot of 10 µl of plasma was transferred to Whatman 903 paper and dried at room temperature. The extraction method was performed by cutting and transferring the paper to a microtube and adding sodium phosphate buffer and internal standard. The mixture was shaken and centrifuged, and a 5-µl aliquot was injected into the analytical system. The optimization of the main parameters that can influence the extraction efficiency was performed using multivariate approaches to obtain the best conditions. The method developed was validated, providing coefficients of determination higher than 0.994 and a lower limit of quantification of 1 mg/L. Within- and between-run precision ranged from 11.4 to 17.30% and from 6.65 to 13.51%, respectively. This method was successfully applied to 75 samples of patients undergoing vancomycin therapy. The method was rapid, simple, and environmentally friendly with satisfactory analytical performance and was advantageous over the laborious and time-consuming methodologies used in therapeutic drug monitoring routine analyses.


Assuntos
Espectrometria de Massas em Tandem , Vancomicina , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Plasma , Monitoramento de Medicamentos/métodos , Teste em Amostras de Sangue Seco/métodos , Imunoensaio/métodos , Reprodutibilidade dos Testes
4.
Genet Mol Biol ; 46(3 Suppl 1): e20230100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37725833

RESUMO

Amongst the sustainable alternatives to increase maize production is the use of plant growth-promoting bacteria (PGPB). Azospirillum brasilense is one of the most well-known PGPB being able to fix nitrogen and produce phytohormones, especially indole-3-acetic acid - IAA. This work investigated if there is any contribution of the bacterium to the plant's IAA levels, and how it affects the plant. To inhibit plant IAA production, yucasin, an inhibitor of the TAM/YUC pathway, was applied. Plantlets' IAA concentration was evaluated through HPLC and dual RNA-Seq was used to analyze gene expression. Statistical differences between the group treated with yucasin and the other groups showed that A. brasilense inoculation was able to prevent the phenotype caused by yucasin concerning the number of lateral roots. Genes involved in the auxin and ABA response pathways, auxin efflux transport, and the cell cycle were regulated by the presence of the bacterium, yucasin, or both. Genes involved in the response to biotic/abiotic stress, plant disease resistance, and a D-type cellulose synthase changed their expression pattern among two sets of comparisons in which A. brasilense acted as treatment. The results suggest that A. brasilense interferes with the expression of many maize genes through an IAA-independent pathway.

5.
J Sep Sci ; 45(1): 258-281, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34726337

RESUMO

Remarkable progress has been achieved in the application of magnetic ionic liquids in microextraction-based procedures. These materials exhibit unique physicochemical properties of ionic liquids featuring additional responses to magnetic fields by incorporating a paramagnetic component within the chemical structure. This intriguing property can open new horizons in analytical extractions because the solvent manipulation is facilitated. Moreover, the tunable chemical structures of magnetic ionic liquids also allow for task-specific extractions that can significantly increase the method selectivity. This review aimed at providing an up-to-date overview of articles involving synthesis, physicochemical properties, and applications of magnetic ionic liquids highlighting recent developments and configurations. Moreover, a section containing critical evaluation and future trends in magnetic ionic liquid-based extractions is included.

6.
J Sep Sci ; 44(9): 1961-1968, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33599065

RESUMO

In this study, a lab-made parallel single-drop microextraction methodology using the magnetic ionic liquid trihexyltetradecylphosphonium tetrachloromanganate (II) as extraction solvent was developed to determine the pesticides tebuconazole, pendimethalin, dichlorodiphenyltrichloroethane, and dichlorodiphenyldichloroethylene in human urine samples. The experimental setup consisted of a 96-well plate system containing a set of magnetic pins that allowed for the manipulation of up to 96 samples simultaneously, providing an enhanced drop stability compared to traditional single-drop microextraction approaches. The optimal conditions employed 5.38 ± 0.55 mg of extraction solvent, 1.5 mL of diluted urine samples (1:10), extraction time of 130 min, and subsequent dilution in 20 µL of acetonitrile. The method exhibited satisfactory analytical performance, with limits of detection of 7.5 µg/L for all analytes and coefficients of determination higher than 0.9955. Intraday and interday precisions ranged from 3 to 17% (n = 3) and 15 to 18% (n = 9), respectively, with relative recovery of analytes ranging from 70 to 122%. The method proposed was successfully applied in two human urine samples and no sign of the analytes was detected. The results demonstrated that the proposed method allowed for cost-effective and high-throughput methodology to be explored as a valuable tool in bioanalytical applications.


Assuntos
Monitoramento Biológico/métodos , Microextração em Fase Líquida/métodos , Praguicidas , COVID-19 , Humanos , Limite de Detecção , Praguicidas/análise , Praguicidas/urina
7.
J Sep Sci ; 43(13): 2657-2665, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32274855

RESUMO

Monitoring biological samples at trace levels of chemicals from anthropogenic actions such as pesticides, pharmaceuticals, and hormones has become a very important subject. This work describes a method for the determination of eight compounds of different chemical classes in human urine samples. Dispersive liquid-liquid microextraction based on magnetic ionic liquids was used as the sample preparation procedure. The main parameters of the method, such as sample dilution, type, and volume of disperser solvent, amount of magnetic ionic liquids, extraction time, and pH were optimized by univariate and multivariate procedures. Validation was performed using a urine sample of a male volunteer in order to obtain a calibration curve and the main analytical parameters of merit such as limits of detection and quantification. Values varied from 3.0 to 7.5 µg/L and from 10 to 25 µg/L, respectively. Satisfactory precisions of 21% for intraday (n = 3) and 16% for interday (n = 9) were achieved. Accuracy was evaluated by relative recovery assays using different urine samples and ranged from 75 to 130%. Robustness was assured by the Lenth method. The validated procedure was applied to five urine samples from different volunteers and the hormone estrone was found in one sample.


Assuntos
Diclofenaco/urina , Estrona/urina , Etinilestradiol/urina , Líquidos Iônicos/química , Microextração em Fase Líquida , Praguicidas/urina , Adulto , Calibragem , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Concentração de Íons de Hidrogênio , Fenômenos Magnéticos , Masculino , Adulto Jovem
8.
J Sep Sci ; 42(7): 1404-1411, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30667178

RESUMO

This study proposes an efficient analytical methodology using a biosorbent (cork) as an extraction phase in disposable pipette extraction technique for the rapid determination of the emerging contaminants methyl paraben, ethyl paraben, benzophenone, 3-(4-methylbenzylidene) camphor and 2-(ethylhexyl)-4-(dimethylamino) benzoate in lake water samples using high-performance liquid chromatography with diode array detection. The optimized conditions were comprised of 800 µL of sample, three cycles of 30 s each for the extraction, pH 6, addition of 30% w/v of NaCl. For the desorption step, the optimized desorption conditions were achieved with 100 µL of a mixture comprised of 50% methanol and 50% acetonitrile v/v, using one cycle of 30 s. Excellent analytical performance was achieved with limits of detection of 0.6 µg/L for methyl paraben to 1.4 µg/L for 3-(4-methylbenzylidene) camphor, and the limit of quantitation varied from 2 µg/L for methyl paraben to 4.3 µg/L 3-(4-methylbenzylidene) camphor, respectively. The correlation coefficients ranged from 0.9962 for ethyl paraben to 0.9980 for methyl paraben. The method accuracy varied from 71-132%, and the intraday precision ranged from 3 to 23% (n = 3) and interday from 9 to 23% (n = 9). The robustness was evaluated through Youden and Lenth's methods and indicated no significant variations in the results.


Assuntos
Lagos/química , Poluentes Químicos da Água/análise , Adsorção , Cromatografia Líquida , Tamanho da Partícula , Propriedades de Superfície
9.
Anal Bioanal Chem ; 410(19): 4689-4699, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29313077

RESUMO

In this study, a rapid and straightforward approach based on magnetic ionic liquids (MIL) as extraction phases and dispersive liquid-liquid microextraction (DLLME) was developed to analyze the hormones estriol, 17-ß-estradiol, 17-α-ethynylestradiol, and estrone in human urine samples. This is the first report of an application of manganese-based MILs compatible with HPLC to extract compounds of biological interest from urine samples. The hydrophobic MILs trihexyltetradecylphosphonium tetrachloromanganate (II) ([P6,6,6,14+]2[MnCl42-]) and aliquat tetrachloromanganate (II) ([Aliquat+]2[MnCl42-]) were employed and the optimized extraction conditions were comprised of 5 mg of MIL ([P6,6,6,14+]2[MnCl42-]), 5 µL of methanol (MeOH) as disperser solvent, and an extraction time of 90 s at sample pH 6. The analytical parameters of merit were determined under optimized conditions and very satisfactory results were achieved, with LODs of 2 ng mL-1 for all analytes, determination coefficients (R2) ranging from 0.9949 for 17-ß-estradiol to 0.9998 for estrone. In addition, good results of method precision were achieved with the intraday (n = 3) varying from 4.7% for 17-ß-estradiol to 19.5% for estriol (both at 5 ng mL-1) and interday precision (evaluated at 100 ng mL-1) ranging from 11.4% for estrone to 17.7% for 17-α-ethynylestradiol and analyte relative recovery evaluated in three real samples ranged from 67.5 to 115.6%. The proposed DLLME/MIL-based approach allowed for a reliable, environmentally friendly and high-throughput methodology with no need for a centrifugation step. Graphical abstract An overview of the rapid and straightforward extraction procedure using DLLME/MIL-based approach.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Estrogênios/urina , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Imãs/química , Adulto , Estradiol/urina , Estrona/urina , Etinilestradiol/urina , Feminino , Humanos , Limite de Detecção , Magnetismo/métodos , Masculino
10.
J Sep Sci ; 40(22): 4431-4438, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28940656

RESUMO

In this study, the viability of two membrane-based microextraction techniques for the determination of endocrine disruptors by high-performance liquid chromatography with diode array detection was evaluated: hollow fiber microporous membrane liquid-liquid extraction and hollow-fiber-supported dispersive liquid-liquid microextraction. The extraction efficiencies obtained for methylparaben, ethylparaben, bisphenol A, benzophenone, and 2-ethylhexyl-4-methoxycinnamate from aqueous matrices obtained using both approaches were compared and showed that hollow fiber microporous membrane liquid-liquid extraction exhibited higher extraction efficiency for most of the compounds studied. Therefore, a detailed optimization of the extraction procedure was carried out with this technique. The optimization of the extraction conditions and liquid desorption were performed by univariate analysis. The optimal conditions for the method were supported liquid membrane with 1-octanol for 10 s, sample pH 7, addition of 15% w/v of NaCl, extraction time of 30 min, and liquid desorption in 150 µL of acetonitrile/methanol (50:50 v/v) for 5 min. The linear correlation coefficients were higher than 0.9936. The limits of detection were 0.5-4.6 µg/L and the limits of quantification were 2-16 µg/L. The analyte relative recoveries were 67-116%, and the relative standard deviations were less than 15.5%.

11.
J Chem Ecol ; 41(4): 360-72, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25912225

RESUMO

A novel in vivo design was used in combination with solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) to characterize the volatile compounds from the skin secretion of two species of tree frogs. Conventional SPME-GC/MS also was used for the analysis of volatiles present in skin samples and for the analysis of volatiles present in the diet and terraria. In total, 40 and 37 compounds were identified in the secretion of Hypsiboas pulchellus and H. riojanus, respectively, of which, 35 were common to both species. Aliphatic aldehydes, a low molecular weight alkadiene, an aromatic alcohol, and other aromatics, ketones, a methoxy pyrazine, sulfur containing compounds, and hemiterpenes are reported here for the first time in anurans. Most of the aliphatic compounds seem to be biosynthesized by the frogs following different metabolic pathways, whereas aromatics and monoterpenes are most likely sequestered from environmental sources. The characteristic smell of the secretion of H. pulchellus described by herpetologists as skunk-like or herbaceous is explained by a complex blend of different odoriferous components. The possible role of the volatiles found in H. pulchellus and H. riojanus is discussed in the context of previous hypotheses about the biological function of volatile secretions in frogs (e.g., sex pheromones, defense secretions against predators, mosquito repellents).


Assuntos
Anuros/metabolismo , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Pele/química , Microextração em Fase Sólida , Especificidade da Espécie
12.
J Chromatogr A ; 1730: 465038, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38905945

RESUMO

This study addresses the analysis of emerging contaminants, often using chromatographic techniques coupled to mass spectrometry. However, sample preparation is often required prior to instrumental analysis, and dispersive liquid-liquid microextraction (DLLME) is a viable strategy in this context. DLLME stands out for its ability to reduce sample and solvent volumes. Notably, dispersive liquid-liquid microextraction using magnetic ionic liquids (MILs) has gained relevance due to the incorporation of paramagnetic components in the chemical structure, thereby eliminating the centrifugation step. A pyrolizer was selected in this work to introduce sample onto the GC column, since the MIL is extremely viscous and incompatible with direct introduction through an autosampler. This study is the first to report the use of a DLLME/MIL technique for sample introduction through a pyrolizer in gas chromatography coupled to mass spectrometry (GC-MS). This approach enables the MIL to be compatible with gas chromatography systems, resulting in optimized analytical and instrument performance. The analysis of polybrominated diphenyl ether flame retardants (PBDEs) was focused on the PBDE congeners 28, 47, 99, 100, and 153 in sewage sludge samples. The [P6,6,6,14+]2[MnCl42-] MIL was thoroughly characterized using UV-Vis, Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy, as well as thermal analysis. In the chromatographic method, a pyrolyzer was used in the sample introduction step (Py-GC-MS), and critical injection settings were optimized using multivariate approaches. Optimized conditions were achieved with a temperature of 220 °C, a pyrolysis time of 0.60 min, and an injection volume of 9.00 µL. DLLME optimization was performed through central compound planning (CCD), and optimized training conditions were achieved with 10.0 mg of MIL, 3.00 µL of acetonitrile (ACN) as dispersive solvent, extraction time of 60 s, and volume of a sample of 8.50 mL. Precision was observed to range from 0.11 % to 12.5 %, with limits of detection (LOD) of 44.4 µg L-1 for PBDE 28, 16.9 µg L-1 for PBDE 47 and PBDE 99, 33.0 µg L-1 for PBDE 100 and 375 µg L-1 for PBDE 153. PBDE 28 was identified and analyzed in the sludge sample at a concentration of 800 µg L-1. The use of MIL in dispersive liquid-liquid microextraction combined with pyrolysis gas chromatography-mass spectrometry enables identification and quantification of PBDEs in sewage sludge samples at concentrations down to the µg L-1 level.


Assuntos
Retardadores de Chama , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados , Líquidos Iônicos , Microextração em Fase Líquida , Esgotos , Microextração em Fase Líquida/métodos , Líquidos Iônicos/química , Esgotos/química , Retardadores de Chama/análise , Retardadores de Chama/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/isolamento & purificação , Limite de Detecção , Pirólise
13.
J Chromatogr A ; 1722: 464892, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608369

RESUMO

In this study, 3D-printing based on fused-deposition modeling (FDM) was employed as simple and cost-effective strategy to fabricate a novel format of rotating-disk sorptive devices. As proof-of-concept, twenty organochlorine and organophosphorus pesticides were determined in water samples through rotating-disk sorptive extraction (RDSE) using honeycomb-like 3D-printed disks followed by gas chromatography coupled to mass spectrometry (GC-MS). The devices that exhibited the best performance were comprised of polyamide + 15 % carbon fiber (PA + 15 % C) with the morphology being evaluated through X-ray microtomography. The optimized extraction conditions consisted of 120 min of extraction using 20 mL of sample at stirring speed of 1100 rpm. Additionally, liquid desorption using 800 µL of acetonitrile for 25 min at stirring speed of 1100 rpm provided the best response. Importantly, the methodology also exhibited high throughput since an extraction/desorption platform that permitted up to fifteen simultaneous extractions was employed. The method was validated, providing coefficients of determination higher than 0.9706 for all analytes; limits of detection (LODs) and limits of quantification (LOQs) ranged from 0.15 to 3.03 µg L-1 and from 0.5 to 10.0 µg L-1, respectively. Intraday precision ranged from 4.01 to 18.73 %, and interday precision varied from 4.83 to 20.00 %. Accuracy was examined through relative recoveries and ranged from 73.29 to 121.51 %. This method was successfully applied to analyze nine groundwater samples from monitoring wells of gas stations in São Paulo. Moreover, the greenness was assessed through AGREEprep metrics, and an overall score of 0.69 was obtained indicating that the method proposed can be considered sustainable.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Clorados , Limite de Detecção , Compostos Organofosforados , Praguicidas , Impressão Tridimensional , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Compostos Organofosforados/análise , Compostos Organofosforados/isolamento & purificação , Praguicidas/análise , Praguicidas/isolamento & purificação , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Adsorção
14.
J Sep Sci ; 36(8): 1410-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23505225

RESUMO

In this study, the experimental extraction conditions on applying headspace solid-phase microextraction and cold fiber headspace solid-phase microextraction (CF-HS-SPME) procedures to samples of six medicinal herbs commonly found in southern Brazil were optimized. The optimized conditions for headspace solid-phase microextraction were found to be an extraction temperature of 60°C and extraction time of 40 min. For CF-HS-SPME, the corresponding values were 60°C and 15 min. In the case of the coating temperature for the CF-HS-SPME system, two approaches were investigated: (i) Temperature of 5°C applied during the whole extraction procedure; and (ii) the use of two fiber temperatures in the same extraction procedure with the aim of extracting the volatile and semivolatile compounds, the ideal condition being 60°C for the first 7.5 min and 5°C for the final 7.5 min. The three extraction procedures were compared. The CF-HS-SPME procedure had good performance only for the more volatile compounds whereas the strategy using two coating temperatures in the same procedure showed good performance for all compounds studied. It was also possible to determine the profile for the volatile fraction of each herb studied applying this technique followed by GC-MS.


Assuntos
Medicina Herbária , Microextração em Fase Sólida/métodos , Temperatura , Volatilização , Brasil , Cromatografia Gasosa-Espectrometria de Massas
15.
Anal Methods ; 15(30): 3752-3757, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475605

RESUMO

This technical note describes a novel and straightforward experimental strategy for the extraction/capture of DNA using magnetic ionic liquid (MIL) followed by real time-polymerase chain reaction (qPCR) analysis. An affordable and low-cost magneto-based multiwell platform was first examined for capturing DNA allowing for simultaneous extractions that increased the analysis throughput of the experimental workflow. This configuration was composed of a series of neodymium rod magnets attached to a multiwell device in which a magneto-active extraction phase (MIL) was suspended for a single drop microextraction (SDME) approach. In this configuration, up to 32 extractions were able to be performed simultaneously, and DNA was successfully extracted from aqueous samples. Furthermore, as a proof-of-concept, this affordable and simple experimental strategy proved to be efficient for the extraction/capture of DNA from challenging samples such as whole blood without any pretreatment. This fact also consists of important feature compared to previous methodologies that required additional steps of sample preparation.


Assuntos
Líquidos Iônicos , DNA , Imãs , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fenômenos Magnéticos
16.
Artigo em Inglês | MEDLINE | ID: mdl-35944416

RESUMO

In this work, hollow-fiber microporous membrane liquid-liquid extraction (HF-MMLLE) was associated with a 96-well plate system for the determination of estrone, 17-ß-estradiol, estriol and 17-α-ethinylestradiol in urine samples. This method exhibited some advantages, such as low cost, easy application, high-throughput and environmentally-friendly aspects. The type of organic solvent to fill the membrane, ionic strength effect, sample dilution, extraction and desorption time, and desorption solvent were examined. After the optimizations, the conditions were comprised of 45 min of extraction, 1-octanol as organic solvent and 15% (w/v) of NaCl; methanol was used as desorption solvent, and the desorption time was fixed at 10 min. The dilution of the sample increased the sensitivity due to the reduction of matrix effects; thus, urine samples were diluted 40-fold. The limits of detection ranged from 0.03 µg L-1 for 17-ß-estradiol to 15 µg L-1 for estrone, and the limits of quantification ranged from 0.1 µg L-1 for 17-ß-estradiol to 10 µg L-1 for estrone. The intra-day precision varied from 1.0% for estriol to 13.3% for 17-α-ethinylestradiol, and inter-day precision varied from 7.3% for estrone to 18.1% for estriol. The relative recoveries varied from 82 to 118%.


Assuntos
Estrona , Microextração em Fase Líquida , Cromatografia Líquida de Alta Pressão/métodos , Estradiol/análise , Estriol , Etinilestradiol , Microextração em Fase Líquida/métodos , Extração Líquido-Líquido , Solventes
17.
J Anal Toxicol ; 46(7): 776-782, 2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518876

RESUMO

Synthetic drugs for recreational purposes are in constant evolution, and their consumption promotes a significant increase in intoxication cases, resulting in damaging public health. The development of analytical methodologies to confirm the consumption of illicit drugs in biological matrices is required for the control of these substances. This work exploited the development of an extraction method based on homogenous liquid-liquid microextraction with switchable hydrophilicity solvent (SHS) as extraction phase for the determination of the synthetic drugs 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine and N-methoxybenzyl-methoxyphenylethylamine derivates (25B, 25C and 25I) in postmortem blood, followed by liquid chromatography coupled to mass spectrometry in tandem. The optimized sample preparation conditions consisted of using 250 µL of ZnSO4 10% and 50 µL of NaOH 1 mol/L in the protein precipitation step; N,N-dimethylcyclohexylamine was used as SHS, 650 µL of a mixture of SHS:HCl 6 mol/L (1:1 v/v), 500 µL of whole blood, 500 µL of NaOH 10 mol/L and 1 min of extraction time. The proposed method was validated, providing determination coefficients higher than 0.99 for all analytes; limit of detection and limit of quantitation ranged from 0.1 to 10 ng/mL; intra-run precision from 2.16% to 9.19%; inter-run precision from 2.39% to 9.59%; bias from 93.57% to 115.71% and matrix effects from 28.94% to 51.54%. The developed method was successfully applied to four authentic postmortem blood samples from synthetic drugs users, and it was found to be reliable with good selectivity.


Assuntos
3,4-Metilenodioxianfetamina , Microextração em Fase Líquida , N-Metil-3,4-Metilenodioxianfetamina , Medicamentos Sintéticos , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Microextração em Fase Líquida/métodos , Hidróxido de Sódio , Solventes/química
18.
Int J Pharm ; 617: 121584, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35202726

RESUMO

Malignant glioblastoma (GB) is the predominant primary brain tumour in adults, but despite the efforts towards novel therapies, the median survival of GB patients has not significantly improved in the last decades. Therefore, localised approaches that treat GB straight into the tumour site provide an alternative to enhance chemotherapy bioavailability and efficacy, reducing systemic toxicity. Likewise, the discovery of protein targets, such as the NIMA-related kinase 1 (Nek1), which was previously shown to be associated with temozolomide (TMZ) resistance in GB, has stimulated the clinical development of target therapy approaches to treat GB patients. In this study, we report an electrospun polyvinyl alcohol (PVA) microfiber (MF) brain-implant prepared for the controlled release of Nek1 protein inhibitor (iNek1) and TMZ or TMZ-loaded nanoparticles. The formulations revealed adequate stability and drug loading, which prolonged the drugs' release allowing a sustained exposure of the GB cells to the treatment and enhancing the drugs' therapeutic effects. TMZ-loaded MF provided the highest concentration of TMZ within the brain of tumour-bearing rats, and it was statistically significant when compared to TMZ via intraperitoneal (IP). All animals treated with either co-therapy formulation (TMZ + iNek1 MF or TMZ nanoparticles + iNek1 MF) survived until the endpoint (60 days), whereas the Blank MF (drug-unloaded), TMZ MF and TMZ IP-treated rats' median survival was found to be 16, 31 and 25 days, respectively. The tumour/brain area ratio of the rats implanted with either MF co-therapy was found to be reduced by 5-fold when compared to Blank MF-implanted rats. Taken together, our results strongly suggest that Nek1 is an important GB oncotarget and the inhibition of Nek1's activity significantly decreases GB cells' viability and tumour size when combined with TMZ treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Animais , Antineoplásicos Alquilantes , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Glioblastoma/metabolismo , Humanos , Quinase 1 Relacionada a NIMA , Ratos , Temozolomida/farmacologia
19.
J Chromatogr A ; 1640: 461944, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33556679

RESUMO

The development and application of alternative green solvents in analytical techniques consist of trends in sample preparation, since this subject represents an important step toward sustainability in experimental procedures. This review is focused on the main theoretical aspects related to deep eutectic solvents (DES), switchable hydrophilicity solvents (SHS) and supramolecular solvents (SUPRAS). Recent applications are highlighted, particularly for the extraction of different analytes from environmental, biological and food matrices. Moreover, novel configurations are emphasized, aiming for efficient, automated and high-throughput procedures. This review also provides some critical points regarding the use of these solvents and their green aspects.


Assuntos
Química Verde/métodos , Microextração em Fase Líquida/métodos , Solventes/química , Interações Hidrofóbicas e Hidrofílicas , Publicações
20.
Talanta ; 223(Pt 2): 121759, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33298275

RESUMO

In this work, a novel and high-throughput parallel-dispersive droplet extraction (Pa-DDE) based on in situ formation of the hydrophobic MILs ([Co(C4IM)4+2]2[NTf2-], [Ni(C4IM)4+2]2[NTf2-] and [Ni(BeIM)4+2]2[NTf2-]) is demonstrated, for the first time, for the determination of benzophenone, metolachlor, triclocarban, pendimethalin, 4-methylbenzylidene camphor, and 2-ethylhexyl-4-methoxycinnamate from aqueous environmental samples. This experimental setup is comprised of a 96-well plate system containing a set of magnetic pins which were used to collect the MIL droplet after in situ formation. This consolidated system enabled simultaneous extraction of up to 96 samples and MIL production in one step. Using this apparatus, sample preparation times of 0.78 min per sample was achieved. The experimental conditions were carefully optimized using uni and multivariate approaches. The optimal conditions were comprised of sample volume of 1.25 mL, 4 mg of [Co(C4IM)4+2]2[Cl-] and 40 µL of LiNTf2 for the in situ formation, and dilution in 20 µL of acetonitrile. The analytical parameters of merit were successfully determined with LODs ranging from 7.5 to 25 µg L-1 and coefficients of determination higher than 0.989. Intraday and interday precision ranged from 6.4 to 20.6% (n = 3) and 11.6-22.9% (n = 9), respectively, with analyte relative recovery ranging between 53.9 and 129.1%.

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