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1.
Carbohydr Polym ; 339: 122257, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823923

RESUMO

Traditional solid phase extraction (SPE) suffers from a lack of specific adsorption. To overcome this problem, a combination of adsorption method and molecular imprinting technology by polydopamine modification was proposed to realize specific recognition of target compounds in SPE, which is of great significance to improve the separation efficiency of SPE. Cellulose hydrogel beads were prepared by dual cross-linking curing method and modified with polydopamine to make them hydrophilic and biocompatible. Subsequently, cellulose hydrogel-based molecularly imprinted beads (MIBs) were synthesized by surface molecular imprinting technology and used as novel column fillers in SPE to achieve efficient adsorption (34.16 mg·g-1) with specific selectivity towards camptothecin (CPT) in 120 min. The simulation and NMR analysis revealed that recognition mechanism of MIBs involved hydrogen bond interactions and Van der Waals effect. The MIBs were successful used in separating CPT from Camptotheca acuminata fruits, exhibiting impressive adsorption capacity (1.19 mg·g-1) and efficient recovery of CPT (81.54 %). Thus, an environmentally friendly column filler for SPE was developed, offering a promising avenue for utilizing cellulose-based materials in the selective separation of natural products.


Assuntos
Camptotecina , Celulose , Hidrogéis , Impressão Molecular , Extração em Fase Sólida , Camptotecina/química , Camptotecina/isolamento & purificação , Celulose/química , Adsorção , Impressão Molecular/métodos , Hidrogéis/química , Extração em Fase Sólida/métodos , Camptotheca/química , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Indóis/química , Frutas/química
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124392, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704997

RESUMO

Nanozyme-based colorimetric sensing has drawn immense attention due to the rapid development of nanozyme in recent years. However, the selectivity of nanozyme-based colorimetric sensing greatly limits its subsequent practical application. It is well known that sample pretreatment can not only improve selectivity by eliminating the sample matrix interference, but also improve sensitivity by enriching trace targets. Based on the easy facile surface modification properties of nanozyme, we rationally designed nanozyme combined with sample pretreatment for colorimetric biosensing, through separation and enrichment, thereby improving the selectivity and sensitivity of the nanozyme colorimetric biosensing. As a proof of concept, the detection of Hg2+ by nanozyme-based colorimetric sensing was used as an example. Magnetic peroxidase-like nanozyme Fe3S4 was designed and synthesized. The selectivity is improved by the specific adsorption of S-Hg bond and the interference elimination after magnetic separation. In addition, the sensitivity is improved by magnetic solid-phase extraction enrichment. Our established colorimetric sensing based on Fe3S4 nanozyme integrated sample pretreatment with an enrichment factor of 100 and the limit of detection (LOD) is 26 nM. In addition, this strategy was successfully applied to detect Hg2+ in environmental water samples. Overall, the strategy showed good selectivity and sensitivity, providing a new practical method for the application of nanozyme-based biosensing in sample pretreatment.


Assuntos
Colorimetria , Limite de Detecção , Mercúrio , Estruturas Metalorgânicas , Extração em Fase Sólida , Mercúrio/análise , Mercúrio/isolamento & purificação , Colorimetria/métodos , Extração em Fase Sólida/métodos , Estruturas Metalorgânicas/química , Catálise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Peroxidase/química , Técnicas Biossensoriais/métodos
3.
J Chromatogr A ; 1727: 464970, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38744187

RESUMO

The extensive usage of neonicotinoid insecticides (NIs) has raised many concerns about their potential harm to environment and human health. Thus, it is of great importance to develop an efficient and reliable method to determine NIs in food samples. In this work, three Zr4+-based metal-organic frameworks functionalized with various numbers of hydroxyl groups were fabricated with a facile one-pot solvothermal method. Among them, dihydroxy modified UiO-66 (UiO-66-(OH)2) exhibited best adsorption performance towards five target NIs. Then, a sensitive and efficient method for detection of NIs from vegetable and fruit samples was established based on dispersive solid phase extraction (dSPE) with UiO-66-(OH)2 as adsorbent coupled with ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Key parameters affecting the dSPE procedure including amounts of adsorbent, adsorption time, eluent solvents and desorption time were investigated. Under the optimal conditions, rapid adsorption of NIs within five minutes was achieved due to the high affinity of UiO-66-(OH)2 towards NIs. The developed method exhibited high sensitivity with limits of detection (LODs) varied from 0.003 to 0.03 ng/mL and wide linearity range over 3-4 orders of magnitude from 0.01 to 500 ng/mL. Furthermore, the established method was applied for determining trace NIs from complex matrices with recoveries ranging from 74.6 to 99.6 % and 77.0-106.8 % for pear and tomato samples, respectively. The results indicate the potential of UiO-66-(OH)2 for efficient enrichment of trace NIs from complex matrices.


Assuntos
Inseticidas , Limite de Detecção , Estruturas Metalorgânicas , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Verduras , Espectrometria de Massas em Tandem/métodos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Inseticidas/análise , Inseticidas/isolamento & purificação , Inseticidas/química , Estruturas Metalorgânicas/química , Adsorção , Verduras/química , Neonicotinoides/análise , Neonicotinoides/química , Neonicotinoides/isolamento & purificação , Frutas/química , Anabasina/análise , Anabasina/química , Contaminação de Alimentos/análise , Zircônio/química , Ácidos Ftálicos
4.
J Chromatogr A ; 1727: 464976, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38744186

RESUMO

A new biosorbent was fabricated by modification of bacterial cellulose biopolymer grafted with lanthanum sulfide decorated carboxylated multiwall carbon nanotube (La2S3@MWCNT@BC). The sorbent was employed in a green alternative dispersive-solid phase extraction of a variety of 14 pesticides in environmental water samples. The analyses were performed using GC-µECD. The properties and structure of La2S3@MWCNT@BC nanocomposite were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and adsorption-desorption isotherms. The composition of the sorbent was also investigated to evaluate the adsorptive properties of its constituents. The impact of various parameters influencing extraction efficacies such as sorbent dose, adsorption time, sample pH, ionic strength, and desorption conditions was investigated. The method was validated by specificity, matrix effect % (-0.4 to -7.4), enrichment factor (4-10), limits of quantification (0.007-0.31 µg L-1), matrix-matched calibration linearity (0.01-200 µg L-1), determination coefficients (r2=0.9921-0.9998), and precision. The optimized method was applied for the analysis of multiclass pesticides in seven environmental and drinking waters and the recoveries were obtained in the 81-108 % range with RSDs of 2.5-4.7 %. This paper is the first report on the synthesis and use of La2S3@MWCNT@BC nanocomposite to extract pesticides from different water samples. The greenness of the procedure was evaluated by the AGREE protocols.


Assuntos
Celulose , Lantânio , Nanotubos de Carbono , Praguicidas , Poluentes Químicos da Água , Nanotubos de Carbono/química , Lantânio/química , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Celulose/química , Praguicidas/análise , Praguicidas/química , Praguicidas/isolamento & purificação , Sulfetos/química , Limite de Detecção , Extração em Fase Sólida/métodos
5.
J Chromatogr A ; 1727: 464988, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38749348

RESUMO

In this research, a novel magnetic nanocomposite (Fe3O4@Zn/Al-LABSA-LDH/ZIF-8) was synthesized using Fe3O4 as the magnetic core, layered double hydroxide (LDH) with linear alkylbenzene sulfonic acid (LABSA) intercalation and zeolitic imidazolate framework-8 (ZIF-8) as the shell. Benefiting from the intercalation of LABSA into LDH combined with ZIF-8, the multiple interactions, including π-π stacking, hydrogen bonding, and electrostatic interactions, conferred high selectivity and good extraction capability to the material towards heterocyclic aromatic amines (HAAs). Fe3O4@Zn/Al-LABSA-LDH@ZIF-8 was used as an adsorbent for magnetic solid-phase extraction (MSPE) to enrich HAAs in thermally processed meat samples, followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) detection. The method exhibited a low detection limit (0.021-0.221 ng/g), good linearity (R2 ≥ 0.9999), high precision (RSD < 7.2 %), and satisfactory sample recovery (89.7 % -107.5 %). This research provides a promising approach for developing novel adsorbents in sample preparation and improving analytical performance.


Assuntos
Aminas , Limite de Detecção , Nanocompostos , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Aminas/análise , Aminas/química , Nanocompostos/química , Extração em Fase Sólida/métodos , Imidazóis/química , Compostos Heterocíclicos/análise , Compostos Heterocíclicos/química , Hidróxidos/química , Zeolitas/química , Carne/análise , Estruturas Metalorgânicas/química , Adsorção , Contaminação de Alimentos/análise , Espectrometria de Massa com Cromatografia Líquida
6.
Mikrochim Acta ; 191(6): 297, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709347

RESUMO

A new detection platform based on a hydroxylated covalent organic framework (COF) integrated with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was constructed and used for detecting adrenergic receptor agonists (ARAs) residues in milk. The hydroxylated COF was prepared by polymerization of tris(4-aminophenyl)amine and 1,3,5-tris(4-formyl-3-hydroxyphenyl)benzene and applied to solid-phase extraction (SPE) of ARAs. This hydroxylated COF was featured with hierarchical flower-like morphology, easy preparation, and copious active adsorption sites. The adsorption model fittings and molecular simulation were applied to explore the potential adsorption mechanism. This detection platform was suitable for detecting four α2- and five ß2-ARAs residues in milk. The linear ranges of the ARAs were from 0.25 to 50 µg·kg-1; the intra-day and the inter-day repeatability were in the range 2.9-7.9% and 2.0-10.1%, respectively. This work demonstrates this hydroxylated COF has great potential as SPE cartridge packing, and provides a new way to determine ARAs residues in milk.


Assuntos
Leite , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Extração em Fase Sólida/métodos , Leite/química , Animais , Espectrometria de Massas em Tandem/métodos , Hidroxilação , Estruturas Metalorgânicas/química , Adsorção , Agonistas Adrenérgicos/química , Agonistas Adrenérgicos/análise , Limite de Detecção , Bovinos
7.
Molecules ; 29(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38731551

RESUMO

The aim of this study is to solve the problems of the complicated pretreatment and high analytical cost in the detection technology of trace drugs and their metabolites in municipal wastewater. A high-performance magnetic sorbent was fsynthesized for the enrichment of trace drugs and their metabolites in wastewater to develop a magnetic solid-phase extraction pretreatment combined with the acoustic ejection mass spectrometry (AEMS) analytical method. The magnetic nanospheres were successfully prepared by magnetic nanoparticles modified with divinylbenzene and vinylpyrrolidone. The results showed that the linear dynamic range of 17 drugs was 1-500 ng/mL, the recovery was 44-100%, the matrix effect was more than 51%, the quantification limit was 1-2 ng/mL, and the MS measurement was fast. It can be seen that the developed magnetic solid-phase extraction (MSPE) method is a good solution to the problems of the complicated pretreatment and analytical cost in the analysis of drugs in wastewater. The developed magnetic material and acoustic excitation pretreatment coupled with mass spectrometry analysis method can realize the low-cost, efficient enrichment, and fast analysis of different kinds of drug molecules in urban sewage.


Assuntos
Drogas Ilícitas , Espectrometria de Massas , Esgotos , Extração em Fase Sólida , Esgotos/análise , Esgotos/química , Extração em Fase Sólida/métodos , Espectrometria de Massas/métodos , Drogas Ilícitas/análise , Poluentes Químicos da Água/análise , Águas Residuárias/análise , Águas Residuárias/química , Nanopartículas de Magnetita/química
8.
Molecules ; 29(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38731605

RESUMO

The aim of this study is to develop a rapid and accurate method for simultaneous analysis of multi-residue pesticides and conduct pesticide monitoring in agricultural products produced by the production and distribution stage in Korea. The representative agricultural products were selected as brown rice, soybean, potato, mandarin, and green pepper and developed using gas chromatography with tandem mass (GC-MS/MS) for the analysis of 272 pesticide residues. The experimental samples were extracted by the QuEChERS-EN method and then cleaned up by using d-SPE, including MgSO4 and primary secondary amine (PSA) sorbents. The established method was validated in accordance with Codex CAC-GL/40, and the limit of quantitation (LOQ) was determined to be 0.01 mg/kg. A total of 243 pesticides satisfied the guidelines in five samples at three levels with values of 60 to 120% (recovery) and ≤45% (coefficient of variation, CV). The remaining 29 pesticides did not satisfy the guidelines, and these pesticides are expected to be used as a screening method for the routine inspection of agricultural products. As a result of analyzing 223 agricultural products in South Korea by applying the simultaneous analysis method, none of the detected levels in the samples exceeded the standard values based on maximum residue limits (MRLs). The developed method in this study will be used to inspect residual pesticides in agricultural products, and it is anticipated to contribute to the distribution of safe agricultural products to consumers.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Resíduos de Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Produtos Agrícolas/química , República da Coreia , Contaminação de Alimentos/análise , Limite de Detecção , Extração em Fase Sólida/métodos
9.
J Sep Sci ; 47(9-10): e2300925, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38726740

RESUMO

Deep eutectic solvents (DESs), as a new type of eco-friendly solvent, have attracted increasing attention on the extraction and separation of flavonoid compounds from various samples, owing to their excellent properties such as biodegradability and ease of handling with very low toxicity. This article provides a status review of the applications of DESs in the extraction of flavonoids, including the introduction of flavonoid compounds, the properties and superiority of DESs, and extraction methods (ultrasonic-assisted extraction, heating reflux extraction, matrix solid-phase dispersion, and solid-phase extraction). Finally, prospects and challenges in the application of DESs on extraction and separation are extensively elucidated and critically reviewed.


Assuntos
Solventes Eutéticos Profundos , Flavonoides , Extração em Fase Sólida , Flavonoides/isolamento & purificação , Flavonoides/química , Solventes Eutéticos Profundos/química , Solventes/química
10.
Anal Methods ; 16(19): 3142-3153, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38713147

RESUMO

We develop and validate a method for the rapid determination and identification of 20 ß-lactamase antibiotics traces in goat's milk by combining the solid phase extraction technology with ultra-high performance liquid chromatography-tandem mass spectrometry. Goat milk samples were extracted with acetonitrile twice. The supernatant was then extracted and cleaned by solid-phase extraction using divinylbenzene and N-vinylpyrrolidone copolymer. The method was validated, with limits of quantification (LOQs) of 0.3 µg kg-1, specificities of 1/3 LOQ, linearities (R2) > 0.99, recoveries of 80-110%, repeatabilities <10.0%, and intermediate precisions <10.0%. The developed method was suitable for the routine analysis of ß-lactamase antibiotics residues in goat's milk and was used to test 76 goat milk samples produced in China.


Assuntos
Antibacterianos , Cabras , Leite , Extração em Fase Sólida , Espectrometria de Massas em Tandem , beta-Lactamases , Animais , Extração em Fase Sólida/métodos , Leite/química , Espectrometria de Massas em Tandem/métodos , Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Resíduos de Drogas/análise , Contaminação de Alimentos/análise , Espectrometria de Massa com Cromatografia Líquida
11.
Environ Sci Technol ; 58(19): 8518-8530, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38693060

RESUMO

Wastewater-based epidemiology (WBE) has been widely implemented around the world as a complementary tool to conventional surveillance techniques to inform and improve public health responses. Currently, wastewater surveillance programs in the U.S. are evaluating integrated approaches to address public health challenges across multiple domains, including substance abuse. In this work, we demonstrated the potential of online solid-phase extraction coupled with liquid chromatography-high-resolution mass spectrometry to support targeted quantification and nontargeted analysis of psychoactive and lifestyle substances as a step toward understanding the operational feasibility of a statewide wastewater surveillance program for substance use assessment in New York. Target screening confirmed 39 substances in influent samples collected from 10 wastewater treatment plants with varying sewershed characteristics and is anticipated to meet the throughput demands as the statewide program scales up to full capacity. Nontarget screening prioritized additional compounds for identification at three confidence levels, including psychoactive substances, such as opioid analgesics, phenethylamines, and cathinone derivatives. Consumption rates of 12 target substances detected in over 80% of wastewater samples were similar to those reported by previous U.S.-based WBE studies despite the uncertainty associated with back-calculations. For selected substances, the relative bias in consumption estimates was sensitive to variations in monitoring frequency, and factors beyond human excretion (e.g., as indicated by the parent-to-metabolite ratios) might also contribute to their prevalence at the sewershed scale. Overall, our study marks the initial phase of refining analytical workflows and data interpretation in preparation for the incorporation of substance use assessment into the statewide wastewater surveillance program in New York.


Assuntos
Águas Residuárias , Águas Residuárias/química , New York , Humanos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Extração em Fase Sólida
12.
Molecules ; 29(10)2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38792139

RESUMO

In the past few decades, considerable scientific strides have been made in the subject of drug analysis in human biological samples. However, the risk caused by incorrect drug plasma levels in patients still remains an important concern. This review paper attempts to investigate the advances made over the last ten years in common sample preparation techniques (SPT) for biological samples based on solid sorbents, including solid-phase extraction (SPE) and solid-phase micro-extraction (SPME), and in particular in the field of molecularly imprinted polymers (MIPs), including non-stimuli-responsive and stimuli-responsive adsorbents. This class of materials is known as 'smart adsorbents', exhibiting tailored responses to various stimuli such as magnetic fields, pH, temperature, and light. Details are provided on how these advanced SPT are changing the landscape of modern drug analysis in their coupling with liquid chromatography-mass spectrometry (LC-MS) analytical techniques, a general term that includes high-performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography (UHPLC), as well as any variation of MS, such as tandem (MS/MS), multiple-stage (MSn), and high-resolution (HRMS) mass spectrometry. Some notes are also provided on coupling with less-performing techniques, such as high-performance liquid chromatography with ultraviolet (HPLC-UV) and diode array detection (HPLC-DAD) detection. Finally, we provide a general review of the difficulties and benefits of the proposed approaches and the future prospects of this research area.


Assuntos
Extração em Fase Sólida , Humanos , Extração em Fase Sólida/métodos , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Microextração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Polímeros Molecularmente Impressos/química , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos
13.
Molecules ; 29(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38792152

RESUMO

Taxus, as a globally prevalent evergreen tree, contains a wealth of bioactive components that play a crucial role in the pharmaceutical field. Taxus extracts, defined as a collection of one or more bioactive compounds extracted from the genus Taxus spp., have become a significant focus of modern cancer treatment research. This review article aims to delve into the scientific background of Taxus extracts and their considerable value in pharmaceutical research. It meticulously sifts through and compares various advanced extraction techniques such as supercritical extraction, ultrasound extraction, microwave-assisted extraction, solid-phase extraction, high-pressure pulsed electric field extraction, and enzymatic extraction, assessing each technology's advantages and limitations across dimensions such as extraction efficiency, extraction purity, economic cost, operational time, and environmental impact, with comprehensive analysis results presented in table form. In the area of drug formulation design, this paper systematically discusses the development strategies for solid, liquid, and semi-solid dosage forms based on the unique physicochemical properties of Taxus extracts, their intended medical uses, and specific release characteristics, delving deeply into the selection of excipients and the critical technical issues in the drug preparation process. Moreover, the article looks forward to the potential directions of Taxus extracts in future research and medical applications, emphasizing the urgency and importance of continuously optimizing extraction methods and formulation design to enhance treatment efficacy, reduce production costs, and decrease environmental burdens. It provides a comprehensive set of preparation techniques and formulation optimization schemes for researchers in cancer treatment and other medical fields, promoting the application and development of Taxus extracts in pharmaceutical sciences.


Assuntos
Extratos Vegetais , Taxus , Taxus/química , Extratos Vegetais/química , Humanos , Composição de Medicamentos/métodos , Extração em Fase Sólida/métodos
14.
Molecules ; 29(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38792172

RESUMO

Pyrethroid pesticides (PYRs) have found widespread application in agriculture for the protection of fruit and vegetable crops. Nonetheless, excessive usage or improper application may allow the residues to exceed the safe limits and pose a threat to consumer safety. Thus, there is an urgent need to develop efficient technologies for the elimination or trace detection of PYRs from vegetables. Here, a simple and efficient magnetic solid-phase extraction (MSPE) strategy was developed for the simultaneous purification and enrichment of five PYRs in vegetables, employing the magnetic covalent organic framework nanomaterial COF-SiO2@Fe3O4 as an adsorbent. COF-SiO2@Fe3O4 was prepared by a straightforward solvothermal method, using Fe3O4 as a magnetic core and benzidine and 3,3,5,5-tetraaldehyde biphenyl as the two building units. COF-SiO2@Fe3O4 could effectively capture the targeted PYRs by virtue of its abundant π-electron system and hydroxyl groups. The impact of various experimental parameters on the extraction efficiency was investigated to optimize the MSPE conditions, including the adsorbent amount, extraction time, elution solvent type and elution time. Subsequently, method validation was conducted under the optimal conditions in conjunction with gas chromatography-mass spectrometry (GC-MS). Within the range of 5.00-100 µg·kg-1 (1.00-100 µg·kg-1 for bifenthrin and 2.5-100 µg·kg-1 for fenpropathrin), the five PYRs exhibited a strong linear relationship, with determination coefficients ranging from 0.9990 to 0.9997. The limits of detection (LODs) were 0.3-1.5 µg·kg-1, and the limits of quantification (LOQs) were 0.9-4.5 µg·kg-1. The recoveries were 80.2-116.7% with relative standard deviations (RSDs) below 7.0%. Finally, COF-SiO2@Fe3O4, NH2-SiO2@Fe3O4 and Fe3O4 were compared as MSPE adsorbents for PYRs. The results indicated that COF-SiO2@Fe3O4 was an efficient and rapid selective adsorbent for PYRs. This method holds promise for the determination of PYRs in real samples.


Assuntos
Praguicidas , Piretrinas , Dióxido de Silício , Extração em Fase Sólida , Verduras , Extração em Fase Sólida/métodos , Dióxido de Silício/química , Verduras/química , Piretrinas/isolamento & purificação , Piretrinas/análise , Piretrinas/química , Praguicidas/isolamento & purificação , Praguicidas/química , Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas , Adsorção , Contaminação de Alimentos/análise , Limite de Detecção , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Compostos Férricos/química , Cobalto
15.
Molecules ; 29(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38792205

RESUMO

This research presents a new, eco-friendly, and swift method combining solid-phase extraction and hydrophobic deep eutectic solvents (DES) with high-performance liquid chromatography (SPE-DES-HPLC) for extracting and quantifying catechin and epicatechin in Shanxi aged vinegar (SAV). The parameters, such as the elution solvent type, the XAD-2 macroporous resin dosage, the DES ratio, the DES volume, the adsorption time, and the desorption time, were optimized via a one-way experiment. A central composite design using the Box-Behnken methodology was employed to investigate the effects of various factors, including 17 experimental runs and the construction of three-dimensional response surface plots to identify the optimal conditions. The results show that the optimal conditions were an HDES (tetraethylammonium chloride and octanoic acid) ratio of 1:3, an XAD-2 macroporous resin dosage of 188 mg, and an adsorption time of 11 min. Under these optimal conditions, the coefficients of determination of the method were greater than or equal to 0.9917, the precision was less than 5%, and the recoveries ranged from 98.8% to 118.8%. The environmentally friendly nature of the analytical process and sample preparation was assessed via the Analytical Eco-Scale and AGREE, demonstrating that this method is a practical and eco-friendly alternative to conventional determination techniques. In summary, this innovative approach offers a solid foundation for the assessment of flavanol compounds present in SAV samples.


Assuntos
Ácido Acético , Catequina , Solventes Eutéticos Profundos , Interações Hidrofóbicas e Hidrofílicas , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodos , Ácido Acético/química , Catequina/química , Catequina/análise , Solventes Eutéticos Profundos/química , Adsorção
16.
J Pharm Biomed Anal ; 245: 116161, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38714135

RESUMO

In this study, Fe3O4@ZnCr-layered double hydroxide/zeolitic imidazolate frameworks-8 (MLDH/ZIF-8) magnetically functionalized composites were synthesized by co-precipitation and in situ growth based on the advantages of LDHs and ZIF-8 using Fe3O4 nanoparticles as a magnetic substrate to obtain adsorbents with excellent performance. Moreover, the composite was used for the efficient enrichment of flavonoids in Chinese herbal medicines. The internal structures and surface properties were characterized by SEM, Fourier transform infrared spectroscopy, X-ray diffraction and so on. MLDH/ZIF-8 exhibited a large specific surface area and good paramagnetic properties. The MLDH/ZIF-8 magnetic composite was used as a magnetic solid-phase extraction (MSPE) adsorbent, and a MLDH/ZIF-8 MSPE-pressurized capillary electrochromatography coupling method was developed for the separation and detection of flavonoids (luteolin, kaempferol and apigenin) in a sample of the Chinese herb Ohwia caudata (Thunberg) H. Ohashi. The relevant parameters affecting the extraction efficiency were optimized to determine the ideal conditions for MSPE. 5 mg of adsorbent in sample solution at pH 6, vortex extraction for 5 min, elution with 1.5 mL of ethyl acetate for 15 min. The method showed good linearity in the concentration range of 3-50 µg mL-1 with correlation coefficients of 0.9934-0.9981, and displayed a relatively LODs of 0.07-0.09 µg mL-1. The spiked recoveries of all analytes ranged from 84.5% to 122.0% with RSDs (n=3) between 4.5% and 7.7%. This method is straightforward and efficient, with promising potential in the separation and analysis of active ingredients in various Chinese herbal medicines.


Assuntos
Medicamentos de Ervas Chinesas , Flavonoides , Hidróxidos , Extração em Fase Sólida , Flavonoides/isolamento & purificação , Flavonoides/análise , Flavonoides/química , Extração em Fase Sólida/métodos , Hidróxidos/química , Medicamentos de Ervas Chinesas/química , Adsorção , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
17.
J Chromatogr A ; 1726: 464965, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733925

RESUMO

Aristolochic acids (AAs) naturally occurring in the herbal genus Aristolochia are associated with a high risk of kidney failure, multiple tumors and cancers. However, approaches with high selectivity and rapidity for measuring AAs in biological samples are still inadequate. Inspired by the mechanism of AAs-induced nephrotoxicity, we designed a hybrid magnetic polymer-porous agarose (denoted as MNs@SiO2M@DNV-A), mimicking the effect of basic and aromatic residues of organic anion transporter 1 (OAT1) for efficient enriching aristolochic acid I (AA I) and aristolochic acid II (AA II) in the plasma. The monomers of vinylbenzyl trimethylammonium chloride (VBTAC), N-vinyl-2-pyrrolidinone (NVP) and divinylbenzene (DVB) were employed to construct the polymer layer, which provided a selective adsorption for AAs by multiple interactions. The porous agarose shell contributed to remove interfering proteins in the plasma samples. A magnetic solid-phase extraction (MSPE) based on the proposed composite enhanced the selectivity toward AA I and AA II in the plasma samples. In combination of HPLC analysis, the proposed method was proved to be applicable to fast and specific quantification of AAs in blood samples, which was characterized by a good linearity, high sensitivity, acceptable recovery, excellent repeatability and satisfactory reusability.


Assuntos
Ácidos Aristolóquicos , Compostos de Amônio Quaternário , Sefarose , Extração em Fase Sólida , Ácidos Aristolóquicos/química , Ácidos Aristolóquicos/isolamento & purificação , Ácidos Aristolóquicos/sangue , Sefarose/química , Extração em Fase Sólida/métodos , Compostos de Amônio Quaternário/química , Cromatografia Líquida de Alta Pressão/métodos , Porosidade , Limite de Detecção , Animais , Humanos , Polímeros/química , Adsorção , Reprodutibilidade dos Testes
18.
Food Chem ; 451: 139427, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692237

RESUMO

Here, we report a monomer planarity modulation strategy for room-temperature constructing molecularly imprinted-covalent organic frameworks (MI-COFs) for selective extraction of ochratoxin A (OTA). 2,4,6-triformylphloroglucinol (Tp) was used as basic building block, while three amino monomers with different planarity were employed as modulators to explore the effect of planarity on the selectivity of MI-COFs. The MI-TpTapa constructed from Tp and the lowest planarity of monomer Tapa gave the highest selectivity for OTA, and was further used as the adsorbent for dispersed-solid phase extraction (DSPE) of OTA in alcohol samples. Coupling MI-TpTapa based DSPE with high-performance liquid chromatography allowed the matrix-effect free determination of OTA in alcohol samples with the limit of detection of 0.023 µg kg-1 and the recoveries of 91.4-97.6%. The relative standard deviation (RSD, n = 6) of intra and inter day was <3.2%. This work provides a new way to construct MI-COFs for selective extraction of hazardous targets.


Assuntos
Contaminação de Alimentos , Impressão Molecular , Ocratoxinas , Extração em Fase Sólida , Ocratoxinas/análise , Ocratoxinas/isolamento & purificação , Ocratoxinas/química , Extração em Fase Sólida/métodos , Extração em Fase Sólida/instrumentação , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Adsorção , Álcoois/química , Álcoois/isolamento & purificação , Estruturas Metalorgânicas/química
19.
Food Res Int ; 183: 114240, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760119

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic organic pollutants found in various environments, notably aquatic ecosystems and the food chain, posing significant health risks. Traditional methods for detecting PAHs in food involve complex processes and considerable reagent usage, raising environmental concerns. This study explores eco-friendly approaches suing solid phases derived from natural sources in matrix solid phase dispersion. We aimed to develop, optimize, and validate a sample preparation technique for seafood, employing natural materials for PAH analysis. Ten natural phases were compared with a commercial reference phase. The methodology involved matrix solid phase dispersion and pressurized liquid extraction, followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Three solid phases (perlite, sweet manioc starch, and barley) showed superior performance in LC-MS/MS and were further evaluated with gas chromatography-tandem mass spectrometry (GC-MS/MS), confirming perlite as the most effective phase. Validation followed Brazilian regulatory guidelines and European Community Regulation 2021/808/EC. The resulting method offered advantages in cost-effectiveness, reduced environmental impact, cleaner extracts, and enhanced analytical performance compared to the reference solid phase and LC-MS/MS. Proficiency analysis confirmed method reliability, with over 50% alignment with green analytical chemistry principles. In conclusion, this study developed an environmentally sustainable sample preparation technique for seafood analysis using natural solid phases, particularly perlite, for PAH determination.


Assuntos
Contaminação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos , Alimentos Marinhos , Espectrometria de Massas em Tandem , Hidrocarbonetos Policíclicos Aromáticos/análise , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Extração em Fase Sólida/métodos , Reprodutibilidade dos Testes , Brasil , Química Verde/métodos
20.
Food Res Int ; 187: 114359, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763643

RESUMO

Chinese Xiaokeng green tea (XKGT) possesses elegant and fascinating aroma characteristics, but its key odorants are still unknown. In this study, 124 volatile compounds in the XKGT infusion were identified by headspace-solid phase microextraction (HS-SPME), stir bar sorptive extraction (SBSE), and solvent extraction-solid phase extraction (SE-SPE) combined with gas chromatography-mass spectrometry (GC-MS). Comparing these three pretreatments, we found HS-SPME was more efficient for headspace compounds while SE-SPE was more efficient for volatiles with higher boiling points. Furthermore, SBSE showed more sensitive to capture ketones then was effective to the application of pretreatment of aroma analysis in green tea. The aroma intensities (AIs) were further identified by gas chromatography-olfactometry (GC-O). According to the AI and relative odor activity value (rOAV), 27 compounds were identified as aroma-active compounds. Quantitative descriptive analysis (QDA) showed that the characteristic aroma attributes of XKGT were chestnut-like, corn-like, fresh, and so on. The results of network analysis showed that (E, Z)-2,6-nonadienal, nonanal, octanal and nerolidol were responsible for the fresh aroma. Similarly, dimethyl sulfide, (E, E)-2,4-heptadienal, (E)-2-octenal and ß-cyclocitral contributed to the corn-like aroma. Furthermore, indole was responsible for the chestnut-like and soybean-like aroma. This study contributes to a better understanding of the molecular mechanism of the aroma characteristics of XKGT.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Olfatometria , Microextração em Fase Sólida , Chá , Compostos Orgânicos Voláteis , Odorantes/análise , Chá/química , Compostos Orgânicos Voláteis/análise , Microextração em Fase Sólida/métodos , Humanos , Camellia sinensis/química , Extração em Fase Sólida/métodos
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