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1.
J Oleo Sci ; 73(7): 963-976, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945925

RESUMO

The objective of this research was to evaluate the efficiency of aqueous enzymatic extraction (AEE) to obtain oil from hemp seeds (Cannabis sativa L.) grown in northern Morocco. Optimisation of AEE extraction parameters, including pH, enzyme concentration (hemicellulase, protease and pectinase), temperature and incubation time, to maximize oil yield was achieved using response surface methodology with a central composite design. For comparison, the solvent extraction (Soxhlet) (SE) method was also used. Optimized hydrolysis conditions involved incubation for 4 hours at 60°C with a pH of 6.5, using a multi-enzyme preparation comprising protease, hemicellulase and pectinase at concentrations of 55, 202.5 and 234 U/mg, respectively. Referring to the conventional Soxhlet extraction (SE), Aqueous Enzymatic Extraction (AEE) achieved a 30.65% oil recovery rate under the optimized parameters mentioned above. The use of enzymes produced an oil that was more stable against oxidation than the solvent-extracted oil, with a peroxide value (PV) of 19.54 and 47.87 meq O 2 /kg, respectively. Furthermore, HPLC-DAD analysis of tocopherol content indicated a higher total tocopherol content (547.2 mg/kg) in Aqueous Enzymatic Extraction (AEE) compared to Soxhlet Extraction (SE) (513.51 mg/kg), with γ-tocopherol being the predominant form. No significant differences in fatty acid composition were observed between the two extraction methods with linoleic acid and alpha-linolenic acid being the predominant constituents.


Assuntos
Cannabis , Glicosídeo Hidrolases , Peptídeo Hidrolases , Óleos de Plantas , Poligalacturonase , Sementes , Cannabis/química , Poligalacturonase/metabolismo , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Glicosídeo Hidrolases/metabolismo , Sementes/química , Peptídeo Hidrolases/metabolismo , Hidrólise , Extração Líquido-Líquido/métodos , Qualidade dos Alimentos , Água , Tocoferóis/análise , Tocoferóis/isolamento & purificação , Concentração de Íons de Hidrogênio , Temperatura , Solventes/química , Química Verde/métodos
2.
Anal Chim Acta ; 1315: 342756, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879204

RESUMO

BACKGROUND: Dried blood spots (DBSs) collected and archived in newborn screening programs (NSP) represent a potentially valuable resource for assessing exposure to a range of organic and inorganic chemicals in newborns. This study develops and optimizes a method to measure polychlorinated naphthalenes (PCNs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs) in DBS using the isotope dilution technique, ultrasonic-assisted liquid-liquid extraction, simple cleanup, triple quadrupole GC-MS/MS analysis, and background correction. RESULTS: We minimize the number of extraction repetitions and the volume of solvent, which helps increase throughput while minimizing the potential for contamination. We obtained high recovery and precision for most compounds, and method detection limits (MDLs) were sufficiently low to detect the more prevalent compounds based on representative sample of the US population. MDLs averaged 0.020 ng/mL (recovery: 107 %, precision: 4 %) for PCNs, 0.021 ng/mL (recovery: 97 %, precision: 4 %) for PCBs, 0.021 ng/mL (recovery: 117 %, precision: 2 %) for OCPs, and 0.021 ng/mL (recovery: 96 %, precision: 3 %) for PBDEs. SIGNIFICANCE AND NOVELTY: To our knowledge, this is the first study presenting an analytical method and for PCNs in DBS, and one of the few studies providing an assessment of method performance for persistent organic pollutants in DBS. The optimized method can be applied to a wide range of applications, including exposure assessment, environmental epidemiology, forensics, environmental surveillance, and ecological monitoring.


Assuntos
Teste em Amostras de Sangue Seco , Naftalenos , Poluentes Orgânicos Persistentes , Espectrometria de Massas em Tandem , Teste em Amostras de Sangue Seco/métodos , Humanos , Naftalenos/sangue , Poluentes Orgânicos Persistentes/sangue , Espectrometria de Massas em Tandem/métodos , Éteres Difenil Halogenados/sangue , Éteres Difenil Halogenados/análise , Bifenilos Policlorados/sangue , Bifenilos Policlorados/análise , Extração Líquido-Líquido/métodos , Hidrocarbonetos Clorados/sangue , Hidrocarbonetos Clorados/análise , Recém-Nascido , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Praguicidas/sangue , Praguicidas/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-38843708

RESUMO

Non-small cell lung cancer (NSCLC) is a significant subtype of lung cancer, and poses a dangerous global threat. One of the current approaches of NSCLC treatment is a combination therapy of adagrasib and pembrolizumab. Accurate monitoring of these drug concentrations in biological fluids is critical for treatment efficacy. Since no method was reported for simultaneous estimation of these drugs, this study focuses on the development of a validated LC-MS/MS bioanalytical method for simultaneous quantification of Adagrasib and Pembrolizumab in rat plasma. The analytes were extracted from the biological matrix through liquid-liquid extraction techniques using acetonitrile as extraction solvent. The analytes were separated on a Waters X-bridge phenyl C18 column, with a mixture of acetonitrile: 0.1 % TFA in water (50: 50 v/v) as mobile phase at an isocratic flow rate of 1.0 mL/min with a runtime of about 5 min. Adagrasib (m/z 605.12 → 201.62), Pembrolizumab (m/z 146.32 → 85.15), and Sotorasib (m/z 561.59 → 218.92) were determined by recording the mass spectra through multiple reaction monitoring in positive mode. The method was validated according to USFDA guidelines. The results demonstrate satisfactory linearity with an r2 value of 0.9998 in the ranges of 40-800 and 10-200 ng/mL, accuracy with mean percentage recovery of 95.22-98.59 % and 96.98-98.57 %, precision indicated with %RSD ranged between 0.39-1.91 % and 0.85-9.03 % for Adagrasib and Pembrolizumab respectively, and other key parameters. The developed method can determine the pharmacokinetic parameters to indicate the efficacy and safety of the drugs, and also can quantify selected drugs simultaneously in biological samples.


Assuntos
Anticorpos Monoclonais Humanizados , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/sangue , Anticorpos Monoclonais Humanizados/química , Animais , Ratos , Reprodutibilidade dos Testes , Masculino , Cromatografia Líquida/métodos , Modelos Lineares , Limite de Detecção , Ratos Sprague-Dawley , Extração Líquido-Líquido/métodos , Espectrometria de Massa com Cromatografia Líquida
4.
J Cell Sci ; 137(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38855848

RESUMO

Liquid-liquid phase separation (LLPS) has increasingly been found to play pivotal roles in a number of intracellular events and reactions, and has introduced a new paradigm in cell biology to explain protein-protein and enzyme-ligand interactions beyond conventional molecular and biochemical theories. LLPS is driven by the cumulative effects of weak and promiscuous interactions, including electrostatic, hydrophobic and cation-π interactions, among polypeptides containing intrinsically disordered regions (IDRs) and describes the macroscopic behaviours of IDR-containing proteins in an intracellular milieu. Recent studies have revealed that interactions between 'charge blocks' - clusters of like charges along the polypeptide chain - strongly induce LLPS and play fundamental roles in its spatiotemporal regulation. Introducing a new parameter, termed 'charge blockiness', into physicochemical models of disordered polypeptides has yielded a better understanding of how the intrinsic amino acid sequence of a polypeptide determines the spatiotemporal occurrence of LLPS within a cell. Charge blockiness might also explain why some post-translational modifications segregate within IDRs and how they regulate LLPS. In this Review, we summarise recent progress towards understanding the mechanism and biological roles of charge block-driven LLPS and discuss how this new characteristic parameter of polypeptides offers new possibilities in the fields of structural biology and cell biology.


Assuntos
Proteínas Intrinsicamente Desordenadas , Proteínas Intrinsicamente Desordenadas/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Humanos , Processamento de Proteína Pós-Traducional , Animais , Eletricidade Estática , Peptídeos/metabolismo , Peptídeos/química , Interações Hidrofóbicas e Hidrofílicas , Extração Líquido-Líquido/métodos , Separação de Fases
5.
Anal Chim Acta ; 1312: 342758, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38834268

RESUMO

BACKGROUND: The selection of the sample treatment strategy is a crucial step in the metabolomics workflow. Solid phase microextraction (SPME) is a sample processing methodology with great potential for use in untargeted metabolomics of tissue samples. However, its utilization is not as widespread as other standard protocols involving steps of tissue collection, metabolism quenching, homogenization, and extraction of metabolites by solvents. Since SPME allows us to perform all these steps in one action in tissue samples, in addition to other advantages, it is necessary to know whether this methodology produces similar or comparable metabolome and lipidome coverage and performance to classical methods. RESULTS: SPME and homogenization with solid-liquid extraction (Homo-SLE) sample treatment methods were applied to healthy murine kidney tissue, followed by comprehensive metabolomics and lipidomics analyses. In addition, it has been tested whether freezing and storage of the tissue causes alterations in the renal metabolome and lipidome, so the analyses were performed on fresh and frozen tissue samples Lipidomics analysis revealed the exclusive presence of different structural membrane and intracellular lipids in the Homo-SLE group. Conversely, all annotated metabolites were detected in both groups. Notably, the freezing of the sample mainly causes a decrease in the levels of most lipid species and an increase in metabolites such as amino acids, purines, and pyrimidines. These alterations are principally detected in a statistically significant way by SPME methodology. Finally, the samples of both methodologies show a positive correlation in all the analyses. SIGNIFICANCE: These results demonstrate that in SPME processing, as long as the fundamentals of non-exhaustive extraction in a pre-equilibrium kinetic regime, extraction in a tissue localized area, the chemistry of the fiber coating and non-homogenization of the tissue are taken into account, is an excellent method to use in kidney tissue metabolomics; since this methodology presents an easy-to-use, efficient, and less invasive approach that simplifies the different sample processing steps.


Assuntos
Rim , Metabolômica , Microextração em Fase Sólida , Microextração em Fase Sólida/métodos , Animais , Metabolômica/métodos , Rim/metabolismo , Rim/química , Camundongos , Extração Líquido-Líquido/métodos , Metaboloma , Masculino , Camundongos Endogâmicos C57BL
6.
Molecules ; 29(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38893413

RESUMO

Beer is a popular alcoholic beverage worldwide. However, limited research has been conducted on identifying key odor-active components in lager-type draft beers for the Chinese market. Therefore, this study aims to elucidate the odor characteristics of the four most popular draft beer brands through a sensory evaluation and an electronic nose. Subsequently, the four draft beers were analyzed through solid-phase microextraction and liquid-liquid extraction using a two-dimensional comprehensive gas chromatography-olfactometry-mass spectrometry analysis (GC×GC-O-MS). Fifty-five volatile odor compounds were detected through GC×GC-O-MS. Through an Aroma Extract Dilution Analysis, 22 key odor-active compounds with flavor dilution factors ≥ 16 were identified, with 11 compounds having odor activity values > one. An electronic nose analysis revealed significant disparities in the odor characteristics of the four samples, enabling their distinct identification. These findings help us to better understand the flavor characteristics of draft beer and the stylistic differences between different brands of products and provide a theoretical basis for objectively evaluating the quality differences between different brands of draft beer.


Assuntos
Cerveja , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Compostos Orgânicos Voláteis , Cerveja/análise , Odorantes/análise , Compostos Orgânicos Voláteis/análise , China , Microextração em Fase Sólida/métodos , Humanos , Olfatometria , Nariz Eletrônico , Extração Líquido-Líquido/métodos , Aromatizantes/análise
7.
J Chromatogr A ; 1726: 464963, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38723493

RESUMO

The monitoring of organic compounds in aquatic matrices poses challenges due to its complexity and time-intensive nature. To address these challenges, we introduce a novel approach utilizing a dual-channel mono (1D) and comprehensive two-dimensional (2D) gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS) system, integrated with a robotic pretreatment platform, for online monitoring of both volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) in water matrices. Employing the robotic platform, we establish a suite of online liquid-liquid extraction (LLE) pretreatment processes for water samples, marking the first instance of such procedures. Leveraging the automatic headspace (HS) module, dual robotic preparations of HS and LLE are sequentially executed to extract VOCs and SVOCs from water matrices. The GC × GC-TOFMS system is distinguished by its dual-channel analytical column configuration, facilitating sequential analysis of VOCs in GC-TOFMS mode and SVOCs in GC × GC-TOFMS mode. Quantitative detection of 55 target VOCs and 104 SVOCs is achieved in a water sample using the instrument system. Our method demonstrates excellent correlation coefficients ranging from 0.990 to 1.000, method detection limits ranging from 0.08 to 4.78 µg L-1, relative standard deviations below 19.3 %, and recovery rates ranging from 50.0 % to 124.0 %. To validate the online monitoring capabilities of our system, we assess target SVOCs at three different concentration levels over a 3-day period. Most compounds exhibit recovery rates ranging from 70.0 % to 130.0 %. Furthermore, we apply our method to analyze a real water sample, successfully identifying over 100 target and nontarget VOCs/SVOCs, including alcohols, aldehydes, ketones, acids, esters, and phenols. These results highlight the efficacy of the proposed analysis system, capable of conducting two distinct analyses in automatic sequence, thereby enhancing the efficiency and accuracy of organic compound analysis in water matrices.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Extração Líquido-Líquido , Robótica , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração Líquido-Líquido/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Limite de Detecção
8.
Sci Rep ; 14(1): 10157, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698072

RESUMO

Extraction of nucleic acids (NAs) is critical for many methods in molecular biology and bioanalytical chemistry. NA extraction has been extensively studied and optimized for a wide range of applications and its importance to society has significantly increased. The COVID-19 pandemic highlighted the importance of early and efficient NA testing, for which NA extraction is a critical analytical step prior to the detection by methods like polymerase chain reaction. This study explores simple, new approaches to extraction using engineered smart nanomaterials, namely NA-binding, intrinsically disordered proteins (IDPs), that undergo triggered liquid-liquid phase separation (LLPS). Two types of NA-binding IDPs are studied, both based on genetically engineered elastin-like polypeptides (ELPs), model IDPs that exhibit a lower critical solution temperature in water and can be designed to exhibit LLPS at desired temperatures in a variety of biological solutions. We show that ELP fusion proteins with natural NA-binding domains can be used to extract DNA and RNA from physiologically relevant solutions. We further show that LLPS of pH responsive ELPs that incorporate histidine in their sequences can be used for both binding, extraction and release of NAs from biological solutions, and can be used to detect SARS-CoV-2 RNA in samples from COVID-positive patients.


Assuntos
COVID-19 , Elastina , Peptídeos , SARS-CoV-2 , Elastina/química , Concentração de Íons de Hidrogênio , Peptídeos/química , COVID-19/virologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/genética , Humanos , Proteínas Intrinsicamente Desordenadas/química , Extração Líquido-Líquido/métodos , Ácidos Nucleicos/isolamento & purificação , Ácidos Nucleicos/química , DNA/química , DNA/isolamento & purificação , Polipeptídeos Semelhantes à Elastina , Separação de Fases
9.
Anal Chim Acta ; 1307: 342624, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719414

RESUMO

BACKGROUND: Pesticides are used in agricultural production for prevent and control crop diseases and pests, but it is easy to cause excessive pesticides residues in agricultural products, polluting the environment and endangering human health. Due to their unmatched and sustainable capabilities, nanoextraction procedures are becoming every day more important in Analytical Chemistry. In particular, nanoconfined liquid phase extraction has shown extraction capabilities toward polar, medium polar, and/or nonpolar substances, which can be easily modulated depending on the nanoconfined solvent used. Furthermore, this "green" technique showed excellent characteristics in terms of recoveries, extraction time (≤1 min), reliability, and versatility. (97) RESULTS: In this work, the advantages of this technique have been coupled with those of filtration membrane extraction, making use of carbon nanofibers (CnFs) growth on carbon microspheres (CµS). This substrate has been deposited on a filter, which combined with gas chromatographic mass spectrometry (GC-MS) analysis successfully employed for the nanoextraction of 30 pesticides (18 organochlorine and 12 pyrethroids) in tea samples. Under the optimized extraction conditions, the linear range with standard solutions was from 1 to 1000 ng mL-1 (R2 ≥ 0.99), the limit of detections in tea samples were in the range 0.56-17.98 µg kg-1. The accuracy of the developed method was evaluated by measuring the extraction recovery of the spiked tea samples, and recoveries between 74.41 % and 115.46 %. (119) SIGNIFICANCE: Considering the versatility of nanoconfined liquid phase extraction and the functionality of the filtration membrane extraction procedure, this new extraction method can be considered a powerful candidate for automatized high-throughput analyses of real samples. (34).


Assuntos
Filtração , Hidrocarbonetos Clorados , Extração Líquido-Líquido , Praguicidas , Piretrinas , Chá , Chá/química , Piretrinas/análise , Piretrinas/isolamento & purificação , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/isolamento & purificação , Extração Líquido-Líquido/métodos , Filtração/métodos , Praguicidas/análise , Praguicidas/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Membranas Artificiais
10.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731845

RESUMO

Moringa oleifera leaves are rich sources of bioactive compounds with potential health benefits, including antioxidants and anti-inflammatory agents. Pressurized liquid extraction (PLE) stands out as a promising technique for effectively extracting valuable compounds from natural sources. In this study, we aimed to optimize PLE parameters, such as temperature, extraction duration, and pressure, to maximize bioactive compound (polyphenols, flavonoids, and ascorbic acid) yield from M. oleifera leaves and evaluate their antioxidant and anti-inflammatory activities. According to the outcomes of this research, the maximum achieved total polyphenol content was 24.10 mg gallic acid equivalents (GAE)/g of dry weight (dw), and the total flavonoid content was increased up to 19.89 mg rutin equivalents (RtE)/g dw. Moreover, after HPLC-DAD analysis, neochlorogenic and chlorogenic acids, catechin and epicatechin, rutin, and narirutin were identified and quantified. As far as the optimum ascorbic acid content is concerned, it was found to be 4.77 mg/g dw. The antioxidant activity was evaluated by three different methods: ferric reducing antioxidant power (FRAP), the DPPH method, and the anti-hydrogen peroxide activity (AHPA) method, resulting in 124.29 µmol ascorbic acid equivalent (AAE)/g dw, 131.28 µmol AAE/g dw, and 229.38 µmol AAE/g dw values, respectively. Lastly, the albumin denaturation inhibition was found to be 37.54%. These findings underscore the potential of PLE as an efficient extraction method for preparing extracts from M. oleifera leaves with the maximum content of bioactive compounds.


Assuntos
Antioxidantes , Moringa oleifera , Extratos Vegetais , Folhas de Planta , Moringa oleifera/química , Folhas de Planta/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Flavonoides/isolamento & purificação , Flavonoides/análise , Flavonoides/química , Flavonoides/farmacologia , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Polifenóis/análise , Polifenóis/química , Ácido Ascórbico/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Pressão , Extração Líquido-Líquido/métodos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação
11.
J Chromatogr A ; 1725: 464944, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38703459

RESUMO

Investigating pesticide exposure and oxidative stress in preschool children is essential for elucidating the determinants of environmental health in early life, with human biomonitoring of urinary pesticide metabolites serving as a critical strategy for achieving this objective. This study demonstrated biomonitoring of 2 phenoxyacetic acid herbicides, 2 organophosphorus pesticide metabolites, and 4 pyrethroid pesticide metabolites in 159 preschool children and evaluated their association with oxidative stress biomarker 8-hydroxydeoxyguanosine. An enzymatic deconjugation process was used to release urinary pesticide metabolites, which were then extracted and enriched by supported liquid extraction, and quantified by ultra-high performance liquid chromatography-tandem mass spectrometry with internal standard calibration. Dichloromethane: methyl tert­butyl ether (1:1, v/v) was optimized as the solvent for supported liquid extraction, and we validated the method for linear range, recovery, matrix effect and method detection limit. Method detection limit of the pesticide metabolites ranged from 0.01 µg/L to 0.04 µg/L, with satisfactory recoveries ranging from 70.5 % to 95.5 %. 2,4,5-Trichlorophenoxyacetic acid was not detected, whereas the other seven pesticide metabolites were detected with frequencies ranging from 10.1 % to 100 %. The concentration of urinary pesticide metabolites did not significantly differ between boys and girls, with the median concentrations being 9.39 µg/L for boys and 4.90 µg/L for girls, respectively. Spearman correlation analysis indicated that significant positive correlations among urinary metabolites. Bayesian kernel machine regression revealed a significant positive association between urinary pesticide metabolites and 8-hydroxydeoxyguanosine. Para-nitrophenol was the pesticide metabolite that contributed significantly to the elevated level of oxidative stress.


Assuntos
8-Hidroxi-2'-Desoxiguanosina , Monitoramento Biológico , Estresse Oxidativo , Praguicidas , Espectrometria de Massas em Tandem , Humanos , Pré-Escolar , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Feminino , Masculino , Monitoramento Biológico/métodos , Praguicidas/urina , Praguicidas/metabolismo , 8-Hidroxi-2'-Desoxiguanosina/urina , Limite de Detecção , Biomarcadores/urina , Extração Líquido-Líquido/métodos , Criança
12.
Chemosphere ; 358: 142201, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692367

RESUMO

Thallium (Tl) is a potential toxicity element that poses significant ecological and environmental risks. Recently, a substantial amount of Tl has been released into the environment through natural and human activities, which attracts increasing attention. The determination of this hazardous and trace element is crucial for controlling its pollution. This article summarizes the advancement and progress in optimizing Tl detection techniques, including atomic absorption spectroscopy (AAS), voltammetry, inductively coupled plasma (ICP)-based methods, spectrophotometry, and X-ray-based methods. Additionally, it introduces sampling and pretreatment methods such as diffusive gradients in thin films (DGT), liquid-liquid extraction, solid phase extraction, and cloud point extraction. Among these techniques, ICP-mass spectrometry (MS) is the preferred choice for Tl detection due to its high precision in determining Tl as well as its species and isotopic composition. Meanwhile, some new materials and agents are employed in detection. The application of novel work electrode materials and chromogenic agents is discussed. Emphasis is placed on reducing solvent consumption and utilizing pretreatment techniques such as ultrasound-assisted processes and functionalized magnetic particles. Most detection is performed in aqueous matrices, while X-ray-based methods applied to solid phases are summarized which provide non-destructive analysis. This work improves the understanding of Tl determination technology while serving as a valuable resource for researchers seeking appropriate analytical techniques.


Assuntos
Monitoramento Ambiental , Tálio , Tálio/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Espectrofotometria Atômica , Extração em Fase Sólida/métodos , Espectrometria de Massas/métodos , Extração Líquido-Líquido/métodos
13.
J Sep Sci ; 47(9-10): e2400142, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38726732

RESUMO

Catechins, renowned for their antioxidant properties and health benefits, are commonly present in beverages, particularly tea and wine. An efficient and cost-effective salting-out assisted liquid-liquid extraction (SALLE) method has been developed and validated for the simultaneous determination of six catechins and caffeine in tea and wine samples using high-performance liquid chromatography-ultraviolet (HPLC-UV). This method demonstrates outstanding performance: linearity (1-120 µg/mL, r2 > 0.999), accuracy (96.5%-103.4% recovery), and precision (≤14.7% relative standard deviation), meeting validation requirements set by the US Food and Drug Administration. The reduced sample size (0.1 g) minimizes matrix interferences and costs without compromising sensitivity. All analytes were detected in Camellia sinensis teas, with green tea displaying the highest total catechin content (47.5-100.1 mg/mL), followed by white and black teas. Analysis of wine samples reveals the presence of catechin in all red and white wines, and epigallocatechin gallate in all red wine samples, highlighting the impact of winemaking processes on catechin content. The SALLE-HPLC-UV approach represents a green alternative by eliminating organic waste, surpassing conventional dilution methods in specificity and sensitivity for catechin determination. AGREEprep assessment emphasizes the strengths of the SALLE procedure, including material reusability, throughput efficiency, minimal sample requirements, low energy consumption, and the absence of organic waste generation.


Assuntos
Cafeína , Catequina , Extração Líquido-Líquido , Chá , Vinho , Cromatografia Líquida de Alta Pressão/métodos , Vinho/análise , Cafeína/análise , Catequina/análise , Chá/química , Extração Líquido-Líquido/métodos , Espectrofotometria Ultravioleta , Raios Ultravioleta
14.
Chemosphere ; 358: 142227, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704046

RESUMO

The widespread detection of perfluorooctanoic acid (PFOA) in the environment has raised significant concerns. The standard PFOA analytical method relies on expensive solid-phase extraction (SPE) and liquid chromatography tandem mass spectrometry (LC-MS/MS) instruments, making routine use prohibitive. We herein proposed a cost-effective yet novel enrichment method for determining PFOA at ng L-1 level. This method entailed a two-step sample preparation process: firstly, PFOA was extracted and enriched using a forward-extraction under acidic conditions, followed by a backward-extraction and enrichment step utilizing alkaline water. The enriched samples were subsequently subjected to a common ion chromatography (IC). Results reveal that maintaining a forward-extraction pH below its pKa value (2.8) is essential, as protonated PFOA proves effective in enhancing the enrichment factor (EF). The challenge lied in driving PFOA from forward-extractant to aqueous backward-extractant due to the decreased hydrophobicity of deprotonated PFOA (log Kow2 = 1.0). In addition, we found that evaporating forward-extractant with alkaline backward-extractant (containing 5% methanol) reduced potential analytical uncertainties associated with PFOA evaporation and sorption. Under optimal conditions, the method achieved a detection limit of 9.2 ng L-1 and an impressive EF value of 719. Comparison with SPE-LC-MS/MS confirmed the proposed method as a promising alternative for PFOA determination. Although initially targeted for PFOA, the novel methodology is likely applicable to preconcentration of other poly-fluoroalkyl substances.


Assuntos
Caprilatos , Fluorocarbonos , Extração Líquido-Líquido , Espectrometria de Massas em Tandem , Poluentes Químicos da Água , Caprilatos/análise , Caprilatos/química , Fluorocarbonos/análise , Fluorocarbonos/isolamento & purificação , Fluorocarbonos/química , Poluentes Químicos da Água/análise , Espectrometria de Massas em Tandem/métodos , Extração Líquido-Líquido/métodos , Cromatografia Líquida/métodos , Extração em Fase Sólida/métodos , Água/química , Monitoramento Ambiental/métodos
15.
J Chromatogr A ; 1728: 465019, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-38810573

RESUMO

A stable isotope dilution-liquid chromatography-tandem mass spectrometry method based on a derivatisation strategy involving an N,N'-carbonylimidazole solution (CDI) with 4-(dimethylamino)-benzenemethanamine was developed for the determination of 11 free fatty acids (FFAs) in human blood samples. Serum samples were subjected to liquid‒liquid extraction and centrifuged, and the supernatant was collected for a two-step derivatisation reaction with a CDI and 4-(dimethylamino)-aniline acetonitrile solution. The derivatised solution was separated on a ACQUITY UPLC HSS T3 column (2.1 × 50 mm, 1.8 µm) column with a mobile phase consisting of water-acetonitrile in gradient elution and then detected by tandem mass spectrometry using electrospray ionisation (ESI) and multiple reaction monitoring (MRM) in positive ion mode and quantified using the isotope internal standard method. The effects of the derivatisation reaction time, temperature and concentration of derivatisation reagents on the response values of the analytes were investigated. The optimal conditions were as follows: 1.0 mg mL-1 CDI acetonitrile solution at 25 °C for 25 min, followed by a reaction with a 1.0 mg mL-1 4-(dimethylamino)-benzenemethanamine acetonitrile solution at 70 °C for 30 min. Under the optimal conditions, the limits of detection (LODs) of the 11 FFAs were in the range of 3.0-14.0 ng mL-1; the limits of quantification (LOQs) were in the range of 8.0-45.0 ng mL-1; and the mean recoveries ranged from 83.4 to 112.8%, with intraday and interday precisions ranging from 0.7 to 9.1% and 3.7-9.5%, respectively. The experimental method is simple in terms of the pretreatment operation, accurate and reliable, and can be applied to the sensitive determination of FFAs in human blood samples.


Assuntos
Ácidos Graxos não Esterificados , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos não Esterificados/sangue , Limite de Detecção , Cromatografia Líquida/métodos , Reprodutibilidade dos Testes , Imidazóis/sangue , Imidazóis/química , Extração Líquido-Líquido/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida de Alta Pressão/métodos , Masculino
16.
Cell Signal ; 120: 111215, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38740235

RESUMO

In recent years, the physical phenomenon of liquid-liquid phase separation has been widely introduced into biological research. Membrane-free organelles have been found to exist in cells that were driven by liquid-liquid phase separation. Intermolecular multivalent interactions can drive liquid-liquid phase separation to form condensates that are independent of other substances in the environment and thus can play an effective role in regulating multiple biological processes in the cell. The way of cell death has also long been a focus in multiple research. In the face of various stresses, cell death-related mechanisms are crucial for maintaining cellular homeostasis and regulating cell fate. With the in-depth study of cell death pathways, it has been found that the process of cell death was also accompanied by the regulation of liquid-liquid phase separation and played a key role. Therefore, this review summarized the roles of liquid-liquid phase separation in various cell death pathways, and explored the regulation of cell fate by liquid-liquid phase separation, with the expectation that the exploration of the mechanism of liquid-liquid phase separation would provide new insights into the treatment of diseases caused by regulated cell death.


Assuntos
Apoptose , Humanos , Animais , Extração Líquido-Líquido/métodos , Separação de Fases
17.
Anal Methods ; 16(16): 2513-2521, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38587209

RESUMO

Sweet tea is a functional herbal tea with anti-inflammatory, anti-diabetic, and other effects, in which phloridzin and trilobatin are two functional compounds. However, the current methods for their quantification are time-consuming, costly, and environmentally unfriendly. In this paper, we propose a rapid method that integrates online pressurized liquid extraction and high-performance liquid chromatography featuring a superficially porous column for fast separation. Moreover, we employ an equal absorption wavelength method to eliminate using multiple standard solutions and relative calibration factors. Our verification process corroborated the technique's selectivity, accuracy, precision, linearity, and detection limitations. Separately, our methodology demonstrated excellent analytical efficiency, cost-effectiveness, and environmental friendliness. Practical application using six distinct batches of sweet tea samples yielded results in congruence with the external standard method. The analytical rate of this technique is up to over 18 times faster than traditional methods, and organic solvent consumption has been reduced to less than 1.5 mL. Therefore, this method provides a valuable way to achieve quality control and green analysis of sweet tea and other herbal teas.


Assuntos
Florizina , Cromatografia Líquida de Alta Pressão/métodos , Florizina/análise , Florizina/química , Chás de Ervas/análise , Taninos Hidrolisáveis/análise , Extração Líquido-Líquido/métodos , Reprodutibilidade dos Testes
18.
Biomed Chromatogr ; 38(7): e5871, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38599686

RESUMO

We report the development and the validation of a sensitive liquid chromatography-mass spectrometry (LC-MS/MS) method for mometasone furoate (MF) analysis in human plasma. Plasma samples were processed through liquid-liquid extraction and analyzed using LC-MS/MS operating in positive mode using multiple reaction monitoring of transitions m/z 520.9 â†’ 355.0 and m/z 525.8 â†’ 355.0 for MF and the internal standard (IS), respectively. Separation was achieved at 1.0 mL/min on a C18 column using a gradient elution of mobile phase of 0.05% ammonia in water (phase A) and acetonitrile (phase B). The assay range was 0.250-100 pg/mL and proved to be accurate and precise MF. Normalized recoveries were consistent and reproducible with a coefficient of variation (CV%) value of 6.0. The CV (%) of the IS normalized matrix factor was not observed in normal, lipemic, and hemolyzed plasmas. Dilutions of 1:10 were accurately quantified. A cycle of three freeze and thaw and stabilities at room temperature and on the autosampler were demonstrated. In addition, MF in the presence of indacaterol and glycopyrronium was proven to be stable at -70°C for at least 157 days. The present method was successfully applied to quantify MF in patients receiving MF, indacaterol, and glycopyrronium as a fixed-dose combination.


Assuntos
Furoato de Mometasona , Espectrometria de Massas em Tandem , Humanos , Furoato de Mometasona/sangue , Furoato de Mometasona/farmacocinética , Furoato de Mometasona/química , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Cromatografia Líquida/métodos , Modelos Lineares , Sensibilidade e Especificidade , Estabilidade de Medicamentos , Extração Líquido-Líquido/métodos , Limite de Detecção , Espectrometria de Massa com Cromatografia Líquida
19.
J Am Chem Soc ; 146(18): 12577-12586, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38683934

RESUMO

Dynamic supramolecular assemblies, driven by noncovalent interactions, pervade the biological realm. In the synthetic domain, their counterparts, supramolecular polymers, endowed with remarkable self-repair and adaptive traits, are often realized through bioinspired designs. Recently, controlled supramolecular polymerization strategies have emerged, drawing inspiration from protein self-assembly. A burgeoning area of research involves mimicking the liquid-liquid phase separation (LLPS) observed in proteins to create coacervate droplets and recognizing their significance in cellular organization and diverse functions. Herein, we introduce a novel perspective on synthetic coacervates, extending beyond their established role in synthetic biology as dynamic, membraneless phases to enable structural control in synthetic supramolecular polymers. Drawing parallels with the cooperative growth of amyloid fibrils through LLPS, we present metastable coacervate droplets as dormant monomer phases for controlled supramolecular polymerization. This is achieved via a π-conjugated monomer design that combines structural characteristics for both coacervation through its terminal ionic groups and one-dimensional growth via a π-conjugated core. This design leads to a unique temporal LLPS, resulting in a metastable coacervate phase, which subsequently undergoes one-dimensional growth via nucleation within the droplets. In-depth spectroscopic and microscopic characterization provides insights into the temporal evolution of disordered and ordered phases. Furthermore, to modulate the kinetics of liquid-to-solid transformation and to achieve precise control over the structural characteristics of the resulting supramolecular polymers, we invoke seeding in the droplets, showcasing living growth characteristics. Our work thus opens up new avenues in the exciting field of supramolecular polymerization, offering general design principles and controlled synthesis of precision self-assembled structures in confined environments.


Assuntos
Polimerização , Substâncias Macromoleculares/química , Substâncias Macromoleculares/síntese química , Polímeros/química , Polímeros/síntese química , Extração Líquido-Líquido/métodos , Estrutura Molecular , Separação de Fases
20.
Anal Bioanal Chem ; 416(13): 3149-3160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38563959

RESUMO

Bats are the second largest mammalian order and are an endangered species group with a strong need for contamination monitoring. To facilitate non-invasive monitoring of the ecological burden in bat populations, a multiresidue method for the simultaneous quantification of 119 analytes including pesticides, persistent organic pollutants (POPs), active pharmaceutical ingredients (APIs), polycyclic aromatic hydrocarbons (PAHs), UV blockers, plasticizers, and other emerging pollutants in bat guano with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed. Sample preparation and clean-up were performed with a modified QuEChERS approach based on DIN EN 15662. The method uses 1.00 g bat guano as sample with acetonitrile and water for liquid-liquid extraction. Phase separation is assisted by citrate-buffered salting out agent. For clean-up of the extract, primary secondary amine (PSA) was combined with graphitized carbon black (GCB). The lower limits of quantification (LLOQ) ranged between 2.5 and 250 µg kg-1. Linearity was shown in a concentration range from the respective LLOQs to 1250 µg kg-1. The median of the mean recovery was 102.4%. Precision was tested at three concentrations. Method and injection precision were adequate with a relative standard deviation (RSD) below 20%. Furthermore, the comparative analysis with LC-MS/MS demonstrated the reliability of the results and provided a valuable extension of the analytical scope. As proof of concept, three guano samples from a German nursery roost of Myotis myotis were analysed. The results show a time-dependent change in contaminant concentration, highlighting the strong need for non-invasive contamination monitoring of whole bat populations.


Assuntos
Quirópteros , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Espectrometria de Massas em Tandem , Animais , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Reprodutibilidade dos Testes , Extração Líquido-Líquido/métodos , Monitoramento Ambiental/métodos
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