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2.
Food Chem ; 450: 139298, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38615532

RESUMO

A convenient, efficient, and green dispersive liquid-liquid microextraction based on the in situ formation of solidified supramolecular solvents combined with high performance liquid chromatography was developed for the determination of four phenylurea herbicides in liquid samples, including monuron, monolinuron, isoproturon, and chlortoluron. Herein, a novel supramolecular solvent was prepared by the in situ reaction of [P4448]Br and NH4PF6, which had the advantages of low melting point, high density, and good dispersibility. In addition, the microscopic morphology and physical properties of supramolecular solvent were characterized, and the extraction conditions were optimized. The results showed that the analytes had good linearity (R2 > 0.9998) within the linear range. The limits of detection and quantification for the four phenylurea herbicides were in the range of 0.13-0.19 µg L-1 and 0.45-0.65 µg L-1, respectively. The prepared supramolecular solvent is suitable for the efficient extraction of phenylurea herbicides in water, fruit juice, and milk.


Assuntos
Sucos de Frutas e Vegetais , Herbicidas , Microextração em Fase Líquida , Leite , Compostos de Fenilureia , Solventes , Microextração em Fase Líquida/métodos , Herbicidas/química , Herbicidas/isolamento & purificação , Herbicidas/análise , Leite/química , Compostos de Fenilureia/isolamento & purificação , Compostos de Fenilureia/química , Compostos de Fenilureia/análise , Sucos de Frutas e Vegetais/análise , Solventes/química , Animais , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise
3.
J Chromatogr A ; 1717: 464692, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38320432

RESUMO

A simple, fast, and efficient ultrasonic-assisted supramolecular solvent microextraction combined with high performance liquid chromatography method was developed for the determination of coumarins in Cortex fraxini, including esculin, esculetin and fraxetin. In this study, a novel supramolecular solvent was prepared with 1-octanol, tetrahydrofuran and water for the first time, and its composition, viscosity, density, structure, and micromorphology were characterized. The prepared supramolecular solvent exhibited vesicular structures and had the characteristics of low viscosity. Through single-factor experiments, response surface methodology and artificial neural network-genetic algorithm, the optimal extraction conditions were obtained as follows: NaCl concentration of 1 mol mL-1, pH value of 10, solid-liquid ratio of 10:1, vortex time of 30 s, ultrasonic power of 100 W, ultrasonic temperature of 60 °C, ultrasonic time of 15 min, centrifugation speed of 5000 rpm, and centrifugation time of 1 min. The results demonstrated that the artificial neural network model exhibited maximum R-values of 0.98703, 0.97440, 0.99836, and 0.95447 for training, testing, validation, and all dataset, respectively. The minimum mean square errors were 0.75, 10.15, 1.99, and 2.63, respectively. This indicated that the predicted values were almost consistent with the actual values. Under the optimal conditions, the total extraction yields of target analytes reached 2.80 %. The calibration curves for each analyte exhibited excellent linearity within the linear range (r > 0.9993). The limits of detection and quantification ranged from 4.87 to 6.55 ng mL-1 and 16.24 to 21.84 ng mL-1, respectively. The recoveries ranged from 98.71 % to 111.01 % with relative standard deviations of less than 3.6 %. The present method had the advantages of short extraction time (15 min) and less solvent consumption (0.5 mL). The prepared supramolecular solvent was proved to have great potential in extracting coumarins from medicinal plants.


Assuntos
Medicamentos de Ervas Chinesas , Microextração em Fase Líquida , Solventes/química , Ultrassom , Microextração em Fase Líquida/métodos , Cumarínicos , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão/métodos , Algoritmos , Limite de Detecção
4.
J Affect Disord ; 348: 26-34, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086449

RESUMO

BACKGROUND: We aimed to examine the influence of gender on serum trace elements and minerals levels in depression, as well as the impact of suicidal ideation (SI) on these gender dimorphisms. METHODS: A total of 260 unmedicated patients with a current major depressive episode were enrolled. The Beck Scale for Suicide Ideation was utilized to evaluate SI. The serum levels of copper, zinc, iron, calcium, phosphorus, and magnesium were quantified. RESULTS: Within the non-SI (NSI) group, females exhibited higher levels of copper (p = 0.001) and phosphorus (p = 0.008), and lower levels of zinc (p = 0.022) and calcium (p = 0.008) compared to males. Conversely, no discernible gender disparities were observed in the SI group (all p > 0.05). Also, no group differences in these trace elements/minerals were observed between the SI and NSI groups (all p > 0.05). Notably, serum iron levels exhibited a significant group-by-sex interaction effect (p = 0.024). Further analysis revealed that iron levels were higher in the SI group than in the NSI group among females (p = 0.048), but lower in females than in males within the NSI group (p < 0.001). Moreover, a positive association between the fourth quantile of serum iron and SI was detected in females (odds ratio [OR] = 2.88, 95 % confidence interval [CI]: 1.08-8.11). CONCLUSIONS: Gender effects on serum trace element/mineral levels were different in depressed patients with and without SI. Female patients were susceptible to SI when serum iron was at the upper end of normal.


Assuntos
Transtorno Depressivo Maior , Oligoelementos , Humanos , Feminino , Masculino , Ideação Suicida , Cobre , Caracteres Sexuais , Cálcio , Minerais , Zinco , Ferro , Fósforo
5.
Sensors (Basel) ; 22(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35459010

RESUMO

The PROSPECT leaf optical radiative transfer models, including PROSPECT-MP, have addressed the contributions of multiple photosynthetic pigments (chlorophyll a and b, and carotenoids) to leaf optical properties, but photo-protective pigment (anthocyanins), another important indicator of vegetation physiological and ecological functions, has not been simultaneously combined within a leaf optical model. Here, we present a new calibration and validation of PROSPECT-MP+ that separates the contributions of multiple photosynthetic and photo-protective pigments to leaf spectrum in the 400-800 nm range using a new empirical dataset that contains multiple photosynthetic and photo-protective pigments (LOPEX_ZJU dataset). We first provide multiple distinct in vivo individual photosynthetic and photo-protective pigment absorption coefficients and leaf average refractive index of the leaf interior using the LOPEX_ZJU dataset. Then, we evaluate the capabilities of PROSPECT-MP+ for forward modelling of leaf directional hemispherical reflectance and transmittance spectra and for retrieval of pigment concentrations by model inversion. The main result of this study is that the absorption coefficients of chlorophyll a and b, carotenoids, and anthocyanins display the physical principles of absorption spectra. Moreover, the validation result of this study demonstrates the potential of PROSPECT-MP+ for improving capabilities in remote sensing of leaf photosynthetic pigments (chlorophyll a and b, and carotenoids) and photo-protective pigment (anthocyanins).


Assuntos
Antocianinas , Carotenoides , Clorofila , Clorofila A , Folhas de Planta/fisiologia
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