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1.
Drug Dev Ind Pharm ; 47(5): 741-747, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34213992

RESUMO

OBJECTIVE: The aim of this study is to develop a rapid and sensitive UPLC-MS/MS approach to determine the sophoridine (SOP) level in rat plasma and the pharmacokinetics of the substance. SIGNIFICANCE: Sophoridine is used as an anti-inflammatory, anti-virus, anti-microbial, and anti-tumor alkaloid. It is essential to explore specific detection methods for the quantitative analysis of SOP in the blood circulation. METHODS: The rat plasma samples were prepared by one-step protein precipitation with acetonitrile. Subsequently, the samples were separated by chromatography using a UPLC BEH C18 reversed-phase with an initial mobile phase of methanol and 0.1% formic acid aqueous solution. The gradient elution was performed at a fixed flow rate of 0.4 mL/min, and multiple reaction monitoring (MRM) mode with an electrospray positive ionization source was employed to detect the transitions of m/z 249.1 → 84.2 for SOP and m/z 264.3 → 69.8 for dendrobine (IS). The entire process required 3.5 min for each sample. RESULTS: A linear correlation was established over the range of 2-2000 ng/mL (r2≥0.9954) for SOP in rat plasma with a lower limit of quantification (LLOQ) at 2 ng/mL. The range of accuracy was tested between 94.90% and 100.80%, and the relative standard deviations (RSDs) toward both intra- and inter-day precision were <10%. Thus, this method was successfully applied to a pharmacokinetic study, and the subsequent results demonstrated a low absolute bioavailability of 2.32%. CONCLUSION: The present study established a reliable method that quantified the SOP concentration in rat plasma after administering a dose of 2 mg/kg intravenously or 20 mg/kg orally.


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Animais , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Quinolizinas , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
2.
Talanta ; 233: 122555, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215058

RESUMO

Growth hormone-releasing peptide-6 (GHRP-6) is part of a group of small synthetic peptides with potent GH-releasing activity that have gained attention in the last two decades by virtue of their cyto- and cardioprotective effects. Despite numerous preclinical studies highlighting the potential cardiovascular benefits of GHRP-6, confirmation of clinical efficacy is still awaited. Recent advances in transdermal drug delivery systems have been made to address challenges related to the poor skin permeation rate of peptides by using pain-free microneedle (MN) devices. Accordingly, highly sensitive and validated analytical methods are required for the potential clinical translation of MN-based peptides. The ultra-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) methods developed in this study aimed to quantify GHRP-6 in biological matrices (plasma, skin) and dissolving polymeric MNs. UHPLC/MS-MS method detection limits of 0.1, 1.1, 0.9 and 1.5 ng/mL were achieved in neat solution, plasma, MN polymer solution, and skin matrices, respectively. Method validation also involved assessment of precision, accuracy, limits of quantification, linearity of matched calibration curves (R2 > 0.990), extraction recovery, matrix effect, stability studies, selectivity, and carry-over effect. Additionally, quality control samples were analyzed at three concentration levels to determine recovery (85-109%) and accuracy/bias (3.2-14.7%). Intra- and inter-day precision were within the range of acceptance (RSDs of 3.0-13.9% and 0.4-14.5%, respectively). The validity and applicability of such methods were successfully demonstrated for transdermal GHRP-6 delivery using GHRP-6-loaded MN patches applied to pig skin.


Assuntos
Oligopeptídeos , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Limite de Detecção , Reprodutibilidade dos Testes , Suínos
3.
Talanta ; 233: 122598, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215086

RESUMO

Determination of concentration of biomarkers of the activation of immune system, uric acid, and creatinine in the saliva can be useful tool for the diagnosis and monitoring of early manifestations of diseases such as malignant, inflammatory, and periodontal disorders. We have developed and validated a high-performance liquid chromatographic method coupled with fluorescence and diode array detection for the separation and quantification of neopterin, tryptophan, creatinine, uric acid, and kynurenine in the human saliva. A separation of these analytes was achieved within 9 min by using second-generation monolithic stationary phase and elution with phosphate buffer. The present method involves very simple sample preparation requiring small amount of sample matrix. The internal standard 3-nitro-l-tyrosine was used for a more precise quantification. The sensitivity of the present method was demonstrated with lower limits of quantification of 0.6 × 10-3 µmol/L for neopterin, 0.725 µmol/L for tryptophan, 0.12 µmol/L for creatinine, 0.18 µmol/L for uric acid, and 0.135 µmol/L for kynurenine. The method was validated with 67 real-life saliva samples collected from patients suffering from breast, ovarian, colorectal, and renal cancer, and 19 saliva samples from patients with periodontal diseases and allowed monitoring of inflammatory response.


Assuntos
Saliva , Ácido Úrico , Biomarcadores , Cromatografia Líquida de Alta Pressão , Humanos , Cinurenina , Triptofano
4.
Talanta ; 233: 122603, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215091

RESUMO

Oligomers are potential migrants from polymers or biopolymers intended to food packaging and they have to be under control. In order to comply with European regulation 10/2011, their concentration in migration must be below 0.01 µg g-1. In this work, fabric phase sorptive extraction (FPSE) was explored as an effective method for extraction and pre-concentration of oligomers migrated from a blend PLA-polyester material. Both food simulant B (3% acetic acid) and juice, as real food, were used for migration experiments. The parameters of FPSE were optimized and the analysis was done by UHPLC-QTOF and UHPLC-QqQ. A total of 21 oligomers were identified, 9 of them coming from PLA and 12 oligomers from the polyester part. These oligomers were formed by adipic acid (AA), phthalic acid (PA) and/or butanediol (BD), ten were cyclic and 11 were linear molecules. Using the optimized FPSE procedure in 3% acetic acid as food simulant, it was possible to identify 3 new compounds that were not detected by direct injection of the simulant into UHPLC-QTOF. In addition, 2 extra compounds, cyclic PA-BD4-AA3 and cyclic PA2-BD3-AA, were only identified in juice samples after FPSE extraction. Besides, in order to quantify the compounds identified, an isolation procedure for PLA oligomers was carried out. Two oligomers were isolated: cyclic (LA)6 and linear HO-(LA)4-H, both with a purity higher than 90% (LA: lactic acid). The highest concentration value was found for the cyclic oligomer [AA-BD]2, that showed 22.63 µg g-1 in 3% acetic acid and 19.64 µg g-1 in juice. The concentration of the total amount of remaining oligomers was below 7.56 µg g-1 in 3% acetic acid as well as in juice.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Biopolímeros , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Poliésteres , Polímeros
5.
Talanta ; 233: 122611, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215095

RESUMO

A simple, selective, and sensitive method involving a miniaturized solid phase extraction step based on a monolithic molecularly imprinted polymer (MIP) directly coupled on-line to UV detection was developed for the determination of benzoylecgonine (BZE) in complex biological samples. Monolithic MIPs were prepared into 100 µm internal diameter fused-silica capillaries either by thermal or photopolymerization. While leading to similar selectivities with respect to BZE, photopolymerization has made it possible to produce monoliths of different lengths that can be adapted to the targeted miniaturized application. The homogeneous morphology of these monolithic MIPs was evaluated by scanning electron microscopy prior to measuring their permeability. Their selectivity was evaluated leading to imprinting factors of 2.7 ± 0.1 for BZE and 4.0 ± 0.6 for cocaine (selected as template for the MIP synthesis) with polymers resulting from three independent syntheses, showing both the high selectivity of the MIPs and the reproducibility of their synthesis. After selecting the appropriate capillary length and the set-up configuration and optimizing the extraction protocol to promote selectivity, the extraction of BZE present in human urine samples spiked at 150, 250, and 500 ng mL-1 was successfully carried out on the monolithic MIP and coupled directly on-line with UV detection. The very clean-baseline of the resulting chromatograms revealing only the peak of interest for BZE illustrated the high selectivity brought by the monolithic MIP. Limits of detection and quantification of 56.4 ng mL-1 and 188.0 ng mL-1 were achieved in urine samples, respectively. It is therefore possible to achieve analytical threshold in accordance with the legislation on BZE detection in urine without the need for an additional chromatographic separation.


Assuntos
Cocaína , Impressão Molecular , Cromatografia Líquida de Alta Pressão , Cocaína/análogos & derivados , Cocaína/análise , Humanos , Polímeros Molecularmente Impressos , Reprodutibilidade dos Testes , Extração em Fase Sólida
6.
Talanta ; 233: 122464, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215101

RESUMO

Medium- and long-chain fatty acids (MLFAs) are essential energy sources in cells and possess vital biological functions. Characteristics of MLFAs in biosamples contributes to the understanding of biological process and finding potential biomarkers for relevant diseases. However, there are obstacles of the MLFAs determination due to their poor ionization efficiency in mass spectrometry and structural similarity of the MLFAs. Herein, a derivatization strategy was applied by labeling with d0-N, N-dimethyl-6,7-dihydro-5H-pyrrolo [3,4-d] pyrimidine-2-amine (d0-DHPP) and detecting with ultra-high performance liquid chromatography combined with tandem mass spectrometry (UHPLC-MS/MS) in multiple reaction monitoring (MRM) mode. The parallel isotope labeled internal standards were generated by tagging d6-DHPP to MLFAs. The simple and rapid derivatization procedure and mild reaction conditions greatly reduced the potential of MLFA degradation during the processing procedure. With the methodology, the chromatographic performance was greatly improved, and the mass spectrum response was enhanced up to 1, 600 folds. Finally, the developed derivatization method was applied to serum samples to analyze the alteration of MLFAs induced by 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) exposure in breast cancer nude mice. The semi-quantitative results demonstrated that the BDE-47 exposure significantly influenced the MLFA metabolism in mice.


Assuntos
Ácidos Graxos , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Isótopos , Camundongos , Camundongos Nus
7.
Talanta ; 233: 122471, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215105

RESUMO

Development of novel functionalized adsorbents for efficient magnetic solid phase extraction (MSPE) is essential for promoting their versatile applications in sample pretreatment. Herein, we report the fabrication of a new polyethyleneimine-600 decorated magnetic microporous organic network nanosphere (Fe3O4@MON-PEI600) for effective MSPE of trace non-steroidal anti-inflammatory drugs (NSAIDs) from different water samples. The core-shelled Fe3O4@MON-PEI600 integrates the synergistic effects of Fe3O4, MON and PEI600, providing facile and effective extraction to NSAIDs via multiple hydrogen bonding, π-π and hydrophobic interactions. The inner MON shell employs π-π and hydrophobic interaction sites and the outer PEI-600 coat acts as the hydrogen bonding doner/receptor, which affords good extraction performance for NSAIDs. Under optimal conditions, the Fe3O4@MON-PEI600-MSPE-HPLC-UV method gives wide linear range (0.14-400 µg L-1), low limits of detection (0.042-0.149 µg L-1), good precisions (intra-day and inter-day RSDs < 4.5%, n = 6), and large enrichment factors (97.0-98.2). Extraction mechanisms and selectivity of Fe3O4@MON-PEI600 are evaluated in detail. Moreover, Fe3O4@MON-PEI600 is successfully applied to enrich the trace NSAIDs in different water samples with the concentrations of 0.7 and 0.8 µg L-1 for 1-naphthylacetic acid, 0.5 and 0.1 µg L-1 for naproxen as well as 0.7 µg L-1 for ibuprofen, respectively. The developed method not only affords a novel and efficient magnetic adsorbent for NSAIDs in aqueous media at trace level, but also provides a new strategy for the rational design and synthesis of multiple functionalized MON composites in sample pretreatment.


Assuntos
Nanosferas , Preparações Farmacêuticas , Adsorção , Anti-Inflamatórios não Esteroides , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Fenômenos Magnéticos , Polietilenoimina , Extração em Fase Sólida , Águas Residuárias
8.
Talanta ; 233: 122512, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215127

RESUMO

A wide range of strategies for efficient chromatography and high MS sensitivity in reversed-phase LC-MS analysis of antibody biopharmaceuticals and their large derivates has been evaluated. They included replacing trifluoroacetic acid with alternative acidifiers, relevancy of elevated column temperature, use of dedicated stationary phases, and counteraction of the suppression effect of trifluoroacetic acid in electrospray ionization. At the column temperature of 60 °C, which significantly reduces in-column protein degradation, the BioResolve RP mAb Polyphenyl, BioShell IgG C4 columns performed best using mobile phases with full or partial replacement of trifluoroacetic acid with difluoroacetic acid in the analysis of intact antibodies. Similarly, 0.03% trifluoroacetic acid in combination with 0.07% formic acid is a good alternative in analyzing antibody chains at 60 °C. Collectively, the addition of 3% 1-butanol to the mobile phase acidified with 0.1% formic acid was the most efficient approach to simultaneously achieving good chromatographic separation and MS sensitivity for intact and reduced antibody biopharmaceuticals. Moreover, this mobile phase combined with the BioResolve RP mAb Polyphenyl column was subsequently demonstrated to provide excellent results for peptide mapping of antibody biopharmaceuticals fully comparable with those obtained using a state-of-the-art column for peptide separation, thus opening an avenue for a single-column multilevel analysis of these biotherapeutics.


Assuntos
Produtos Biológicos , Anticorpos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ácido Trifluoracético
9.
Talanta ; 233: 122522, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215137

RESUMO

Aldehydes are toxic carbonyl compounds that are identified in various matrices surrounding us. For instance, aldehydes could be formed during the cooking and frying of foods which affects the food quality and safety. Derivatization is a must for the determination of aldehydes as they lack intrinsic chromophoric groups. 2,4-Dinitrophenyl hydrazine (DNPH) is the most used derivatizing reagent for aldehydes and the formed hydrazones could be determined by either HPLC-UV or LC-MS. However, UV detection is non-sensitive, and the MS equipment is expensive and not widely available. Thus, herein we report a smart chemiluminescence (CL) detection method for the DNPH aldehydes derivatives. These derivatives are supposed to possess photosensitization ability due to the presence of strong chromophoric structures; nitrobenzene and phenyl hydrazone. Upon their UV irradiation, singlet oxygen is found to be produced which then converts the DNPH-aldehyde derivative into hydroperoxide. Next, the hydroperoxide reacts with luminol in an alkaline medium producing a strong CL. An HPLC system with online UV irradiation and online reaction with luminol followed by CL detection was constructed and used for the determination of aldehydes after their derivatization with DNPH. The developed method showed excellent sensitivity with detection limits down to 1.5-18.5 nM. The achieved sensitivity is superior to that obtained by HPLC-UV and LC-MS detection methods for DNPH-aldehydes derivatives. Additionally, our approach is an chemiluminogenic where the DNPH reagent itself does not produce CL which is an excellent advantage. The method was applied successfully for the determination of aldehydes in canola oil samples using simple liquid-liquid extraction showing good recovery (87.0-106.0%), accuracy (87.2-106.6), and precision (RSD≤10.2%). After analysis of fresh and heated oil samples, it was demonstrated that heating of oil, even for short time, strongly elevated the level of their aldehydes' content. At last, it was found that the results of the analysis of aldehydes in oil samples using the proposed method perfectly matched those obtained by a reference LC-MS method.


Assuntos
Aldeídos , Luminol , Cromatografia Líquida de Alta Pressão , Hidrazinas , Luminescência , Fenil-Hidrazinas
10.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201056

RESUMO

The present investigation aimed to provide novel information on the chemical composition and in vitro bioaccessibility of bioactive compounds from raw citrus pomaces (mandarin varieties Clemenule and Ortanique and orange varieties Navel and Valencia). The effects of the baking process on their bioaccessibility was also assessed. Samples of pomaces and biscuits containing them as an ingredient were digested, mimicking the human enzymatic oral gastrointestinal digestion process, and the composition of the digests were analyzed. UHPLC-MS/MS results of the citrus pomaces flavonoid composition showed nobiletin, hesperidin/neohesperidin, tangeretin, heptamethoxyflavone, tetramethylscutellarein, and naringin/narirutin. The analysis of the digests indicated the bioaccessibility of compounds possessing antioxidant [6.6-11.0 mg GAE/g digest, 65.5-97.1 µmol Trolox Equivalents (TE)/g digest, and 135.5-214.8 µmol TE/g digest for total phenol content (TPC), ABTS, and ORAC-FL methods, respectively; significant reduction (p < 0.05) in Reactive Oxygen Species (ROS) formation under tert-butyl hydroperoxide (1 mM)-induced conditions in IEC-6 and CCD-18Co cells when pre-treated with concentrations 5-25 µg/mL of the digests], anti-inflammatory [significant reduction (p < 0.05) in nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages], and antidiabetic (IC50 3.97-11.42 mg/mL and 58.04-105.68 mg/mL for α-glucosidase and α-amylase inhibition capacities) properties in the citrus pomaces under study. In addition, orange pomace biscuits with the nutrition claims "no-added sugars" and "source of fiber", as well as those with good sensory quality (6.9-6.7, scale 1-9) and potential health promoting properties, were obtained. In conclusion, the results supported the feasibility of citrus pomace as a natural sustainable source of health-promoting compounds such as flavonoids. Unfractionated orange pomace may be employed as a functional food ingredient for reducing the risk of pathophysiological processes linked to oxidative stress, inflammation, and carbohydrate metabolism, such as diabetes, among others.


Assuntos
Citrus sinensis/química , Citrus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Digestão/fisiologia , Flavonoides/química , Flavonoides/farmacologia , Frutas/química , Trato Gastrointestinal/fisiologia , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Células RAW 264.7 , Espectrometria de Massas em Tandem/métodos
11.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201178

RESUMO

The health benefits of green tea are associated with its high catechin content. In scientific studies, green tea is often prepared with deionized water. However, casual consumers will simply use their local tap water, which differs in alkalinity and mineral content depending on the region. To assess the effect of water hardness on catechin and caffeine content, green tea infusions were prepared with synthetic freshwater in five different hardness levels, a sodium bicarbonate solution, a mineral salt solution, and deionized water. HPLC analysis was performed with a superficially porous pentafluorophenyl column. As water hardness increased, total catechin yield decreased. This was mostly due to the autoxidation of epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Epicatechin (EC), epicatechin gallate (ECG), and caffeine showed greater chemical stability. Autoxidation was promoted by alkaline conditions and resulted in the browning of the green tea infusions. High levels of alkaline sodium bicarbonate found in hard water can render some tap waters unsuitable for green tea preparation.


Assuntos
Cafeína/química , Catequina/química , Chá/química , Água/química , Camellia sinensis/química , Catequina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Dureza , Minerais/química , Extratos Vegetais/química
12.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201343

RESUMO

Taurine (Tau) has some important ameliorating effects on human health and is present in bivalve. For the selective analysis of Tau with other amino acids, we designed a derivatization reagent, 2,5-dioxopyrrolidin-1-yl(4-(((2-nitrophenyl)sulfonyl)oxy)-6-(3-oxomorpholino)quinoline-2-carbonyl)pyrrolidine-3-carboxylate (Ns-MOK-ß-Pro-OSu). After derivatization with Ns-MOK-ß-Pro-OSu, amino acids with Tau in Japanese littleneck clams were determined through ultra-high-performance-liquid chromatography with high-resolution tandem mass spectrometry (UHPLC-HRMS/MS) using an octadecyl silica column. We could detect 18 amino acids within 10 min. Tau, valine, glutamine, glutamic acid, and arginine in the clams were determined in the negative ion mode using the characteristic fragment ion, C6H4N1O5S, which corresponded to the 2-nitrobenzenesulfonylate moiety. The fragment ion, C6H4N1O5S, was recognized as a common feature regardless of the amino acid to be derivatized, and it was convenient for detecting amino acid derivatives with high selectivity and sensitivity. Therefore, highly selective quantification using UHPLC-HRMS/MS was possible using Ns-MOK-ß-Pro-OSu.


Assuntos
Aminoácidos/química , Cromatografia Líquida de Alta Pressão/métodos , Indicadores e Reagentes/química , Espectrometria de Massas em Tandem/métodos , Taurina/química , Ácidos Carboxílicos/química , Pirrolidinas/química , Quinolinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos
13.
Molecules ; 26(12)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203624

RESUMO

Millettia pulchra is traditionally used for treating diseases, including joint pain, fever, anemia, and allergies. It is also a potential resource of natural flavonoid derivatives, which represents major constituents of this plant. This study aimed to isolate the major compounds from M. pulchra radix, develop and validate the HPLC-PDA method to determine their contents, and optimize its extraction. Four major flavonoid derivatives (karanjin, lanceolatin B, 2",2"-dimethylpyrano-[5″,6″:7,8]-flavone, and pongamol) were isolated using silica gel column chromatography, crystallization techniques in large amounts with high purities (>95%). A simple, accurate high-performance liquid chromatography-photodiode array (HPLC-PDA) detection method has been developed and validated with significantly statistical impacts according to International Conference on Harmonization (ICH) guidelines. The Response Surface Methodology (RSM), Artificial Neural Network (ANN) models were employed to predictive performance and optimization of the extraction process. The optimized conditions for the extraction of major flavonoids were: extraction time (twice), solvent/material ratio (9.5), and ethanol concentration (72.5%). Our research suggests an effective method, which will be helpful for quality control in the pharmaceutical development of this species.


Assuntos
Flavonoides/química , Flavonoides/isolamento & purificação , Millettia/química , Antioxidantes/química , China , Cromatografia Líquida de Alta Pressão/métodos , Etanol/química , Millettia/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Solventes/química
14.
Molecules ; 26(12)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204777

RESUMO

Phenolic compounds are currently the most investigated class of functional components in quinoa. However, great variability in their content emerged, because of differences in sample intrinsic and extrinsic characteristics; processing-induced factors; as well as extraction procedures applied. This study aimed to optimize phenolic compound extraction conditions in black quinoa seeds by Response Surface Methodology. An ultrasound-assisted extraction was performed with two different mixtures; and the effect of time; temperature; and sample-to-solvent ratio on total phenolic content (TPC) was investigated. Data were fitted to a second-order polynomial model. Multiple regression analysis and analysis of variance were used to determine the fitness of the model and optimal conditions for TPC. Three-dimensional surface plots were generated from the mathematical models. TPC at optimal conditions was 280.25 ± 3.94 mg of Gallic Acid Equivalent (GAE) 100 g-1 dm upon extraction with aqueous methanol/acetone, and 236.37 ± 5.26 mg GAE 100 g-1 dm with aqueous ethanol mixture. The phenolic profile of extracts obtained at optimal conditions was also investigated by HPLC. The two extracting procedures did not show different specificities for phenolic compounds but differed in the extraction yield.


Assuntos
Chenopodium quinoa/química , Fenóis/química , Fenóis/isolamento & purificação , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Ultrassom/métodos
15.
Molecules ; 26(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207051

RESUMO

An ultra-high performance liquid chromatography coupled to tandem mass spectrometry method is proposed for the determination of the major ergot alkaloids (ergometrine, ergosine, ergotamine, ergocornine, ergokryptine, ergocristine) and their epimers (ergometrinine, ergosinine, ergotaminine, ergocorninine, ergokryptinine, and ergocristinine) in oat-based foods and food supplements. A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure was applied as sample treatment, reducing the consumption of organic solvent and increasing sensitivity. This method involved an extraction with acetonitrile and ammonium carbonate (85:15, v/v) and a clean-up step based on dispersive solid-phase extraction, employing a mixture of C18/Z-Sep+ as sorbents. Procedural calibration curves were established and limits of quantification were below 3.2 µg/kg for the studied compounds. Repeatability and intermediate precision (expressed as RSD%) were lower than 6.3% and 15%, respectively, with recoveries ranging between 89.7% and 109%. The method was applied to oat-based products (bran, flakes, flour, grass, hydroalcoholic extracts, juices, and tablets), finding a positive sample of oat bran contaminated with ergometrine, ergosine, ergometrinine, and ergosinine (total content of 10.7 µg/kg).


Assuntos
Avena/química , Alcaloides de Claviceps/química , Alimento Funcional/análise , Carbonatos/química , Cromatografia Líquida de Alta Pressão/métodos , Ergolinas/química , Ergonovina/química , Ergotaminas/química , Contaminação de Alimentos/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
16.
Molecules ; 26(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207320

RESUMO

We evaluated mycophenolic acid (MPA) limited sampling strategies (LSSs) established using multiple linear regression (MLR) in children with nephrotic syndrome treated with mycophenolate mofetil (MMF). MLR-LSS is an easy-to-determine approach of therapeutic drug monitoring (TDM). We assessed the practicability of different LSSs for the estimation of MPA exposure as well as the optimal time points for MPA TDM. The literature search returned 29 studies dated 1998-2020. We applied 53 LSSs (n = 48 for MPA, n = 5 for free MPA [fMPA]) to predict the area under the time-concentration curve (AUCpred) in 24 children with nephrotic syndrome, for whom we previously determined MPA and fMPA concentrations, and compare the results with the determined AUC (AUCtotal). Nine equations met the requirements for bias and precision ±15%. The MPA AUC in children with nephrotic syndrome was predicted the best by four time-point LSSs developed for renal transplant recipients. Out of five LSSs evaluated for fMPA, none fulfilled the ±15% criteria for bias and precision probably due to very high percentage of bound MPA (99.64%). MPA LSS for children with nephrotic syndrome should include blood samples collected 1 h, 2 h and near the second MPA maximum concentration. MPA concentrations determined with the high performance liquid chromatography after multiplying by 1.175 may be used in LSSs based on MPA concentrations determined with the immunoassay technique. MPA LSS may facilitate TDM in the case of MMF, however, more studies on fMPA LSS are required for children with nephrotic syndrome.


Assuntos
Ácido Micofenólico/metabolismo , Síndrome Nefrótica/metabolismo , Adolescente , Coleta de Amostras Sanguíneas/métodos , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Transplante de Rim/métodos , Modelos Lineares , Masculino , Análise Multivariada , Manejo de Espécimes/métodos
17.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208500

RESUMO

An ultra-high performance liquid chromatography tandem mass spectrometry method was developed and validated for the sensitive determination and unambiguous confirmation of residues of per and polyfluorinated alkyl substances (PFAS) in breastmilk, retail milk and infant formulas following two sample preparation methods. Sample pre-treatment was carried out by a simplified QuEChERS method without requiring dSPE or any further clean-up. The method was validated in accordance with the requirements of Commission Decision 657/2002/EC with slight modifications. The method displayed good linearity with R2 ranging from 0.9843-0.9998 for all target PFAS. The recovery and within-laboratory reproducibility of the method (n = 63) were in the range 60-121% and 5-28%, respectively. The decision limit, detection capability and limit of quantitation ranged from 30-60 ng kg-1 to 40-100 ng kg-1 and 5-50 ng kg-1, respectively. Acceptable matrix effect values in the range -45-29% were obtained with uncertainty of measurement lower than 25% for all target PFAS. The method displays its suitability for the sensitive and high-throughput confirmatory analysis of C4-C14 PFAS in breastmilk, dairy milk and infant formulas.


Assuntos
Fórmulas Infantis/química , Leite Humano/química , Leite/química , Adulto , Animais , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Fluorcarbonetos/análise , Fluorcarbonetos/química , Humanos , Recém-Nascido , Reprodutibilidade dos Testes , Extração em Fase Sólida , África do Sul , Espectrometria de Massas em Tandem/métodos
18.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208757

RESUMO

BACKGROUND: Pesticide residues are a threat to the health of the global population, not only to farmers, applicators, and other pesticide professionals. Humans are exposed through various routes such as food, skin, and inhalation. This study summarizes the different methods to assess and/or estimate human exposure to pesticide residues of the global population. METHODS: A systematic search was carried out on Scopus and web of science databases of studies on human exposure to pesticide residues since 2019. RESULTS: The methods to estimate human health risk can be categorized as direct (determining the exposure through specific biomarkers in human matrices) or indirect (determining the levels in the environment and food and estimating the occurrence). The role that analytical techniques play was analyzed. In both cases, the application of generic solvent extraction and solid-phase extraction (SPE) clean-up, followed by liquid or gas chromatography coupled to mass spectrometry, is decisive. Advances within the analytical techniques have played an unquestionable role. CONCLUSIONS: All these studies have contributed to an important advance in the knowledge of analytical techniques for the detection of pesticide levels and the subsequent assessment of nonoccupational human exposure.


Assuntos
Exposição Ambiental/análise , Resíduos de Praguicidas/efeitos adversos , Praguicidas/efeitos adversos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Indicadores Básicos de Saúde , Humanos , Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Praguicidas/análise , Extração em Fase Sólida/métodos , Solventes/química
19.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206066

RESUMO

The phytochemical composition of leaves, stems, pericarps and rhizomes ethanolic extracts of Asparagus acutifolius were characterized by HPLC-DAD-MS. A. acutifolius samples contain at least eleven simple phenolics, one flavonon, two flavonols and six steroidal saponins. The stem extracts showed the highest total phenolic acid and flavonoid contents, where cafeic acid and rutin were the main compounds. No flavonoids were detected in the leaf, pericarp or rhizome while caffeic acid and ferulic acid were the predominant. Steroidal saponins were detected in the different plant parts of A. acutifolius, and the highest contents were found in the rhizome extracts. The stem extracts exhibited the highest antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) and the highest 2,2-azino-bis (3 ethylbenzothiazoline-6-sulphonic acid) (ABTS) scavenging activity was found in the pericarp extracts. The rhizome and leaf extracts showed a potent cytotoxic activity against HCT-116 and HepG2 cell lines. Moreover, the pericarp and rhizome extracts revealed a moderate lipase inhibitory activity. The leaf and rhizome extracts were screened for their antimicrobial activity against human pathogenic isolates. The leaf extract exhibited a powerful inhibitory activity against all the bacteria and fungi tested.


Assuntos
Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Asparagus (Planta)/química , Lipase/antagonistas & inibidores , Compostos Fitoquímicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células HCT116 , Células Hep G2 , Humanos , Espectrometria de Massas , Especificidade de Órgãos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Folhas de Planta/química , Caules de Planta/química , Rizoma/química
20.
Molecules ; 26(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34198975

RESUMO

The past decade has seen growing interest in marine natural pigments for biotechnological applications. One of the most abundant classes of biological pigments is the tetrapyrroles, which are prized targets due their photodynamic properties; porphyrins are the best known examples of this group. Many animal porphyrinoids and other tetrapyrroles are produced through heme metabolic pathways, the best known of which are the bile pigments biliverdin and bilirubin. Eulalia is a marine Polychaeta characterized by its bright green coloration resulting from a remarkably wide range of greenish and yellowish tetrapyrroles, some of which have promising photodynamic properties. The present study combined metabolomics based on HPLC-DAD with RNA-seq transcriptomics to investigate the molecular pathways of porphyrinoid metabolism by comparing the worm's proboscis and epidermis, which display distinct pigmentation patterns. The results showed that pigments are endogenous and seemingly heme-derived. The worm possesses homologs in both organs for genes encoding enzymes involved in heme metabolism such as ALAD, FECH, UROS, and PPOX. However, the findings also indicate that variants of the canonical enzymes of the heme biosynthesis pathway can be species- and organ-specific. These differences between molecular networks contribute to explain not only the differential pigmentation patterns between organs, but also the worm's variety of novel endogenous tetrapyrrolic compounds.


Assuntos
Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Metabolômica/métodos , Poliquetos/genética , Tetrapirróis/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Epiderme/metabolismo , Redes e Vias Metabólicas , Especificidade de Órgãos , Fármacos Fotossensibilizantes/metabolismo , Poliquetos/metabolismo , Análise de Sequência de RNA , Especificidade da Espécie , Tetrapirróis/genética
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