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1.
Adv Med Sci ; 66(1): 155-161, 2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33592358

RESUMO

PURPOSE: Meteorin-like protein (METRNL) (also known as IL-41), recently identified as a myokine, is released in response to muscle contraction. It improves the skeletal muscle insulin sensitivity through exerting a beneficial anti-inflammatory effect. However, no independent studies have been published to verify the effects of METRNL on human umbilical vein endothelial cells (HUVECs) and THP-1 human monocytes. MATERIALS AND METHODS: The levels of NFκB and IκB phosphorylation as well as the expression of adhesion molecules were assessed by Western blotting analysis. Cell adhesion assay demonstrated the interactions between HUVEC and THP-1 â€‹cells. We used enzyme-linked immunosorbent assay (ELISA) to measure the levels of TNFα and MCP-1 in culture medium. RESULTS: Treatment with METRNL suppressed the secretion of TNFα and MCP-1 as well as NFκB and IκB phosphorylation and inflammatory markers in lipopolysaccharide (LPS)-treated HUVECs and THP-1 â€‹cells. Furthermore, treatment with METRNL ameliorated LPS-induced attachment of THP-1 monocytes to HUVECs via inhibition of adhesion molecule expression and apoptosis. Treatment of HUVEC and THP-1 â€‹cells with METRNL enhanced AMPK phosphorylation and PPARδ expression in a dose-dependent manner. Small interference (si) RNA-mediated suppression of AMPK or PPARδ restored all these changes. CONCLUSIONS: It has therefore been shown that METRNL ameliorates inflammatory responses through AMPK and PPARδ-dependent pathways in LPS-treated HUVEC. In sum, the current study may suggest the suppressive potential of METRNL against endothelial inflammation.

2.
Talanta ; 225: 122031, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592760

RESUMO

Surface-enhanced Raman spectroscopy (SERS) is a powerful and high-speed detection technology. It provides information on molecular fingerprint recognition with ultrahigh sensitive detection. However, it shows poor anti-interference capacity against complex matrices. Molecularly imprinted polymers (MIPs) can achieve specific recognition of targets from complex matrices. Through introducing the MIP separation system, the MIP-SERS chemical sensor can effectively overcome the limitation of complex matrix interference, and further improve the stability of sensors for detection. Herein, the materials and structures of integrated MIP-SERS sensors are systematically reviewed, and its application as a sensor for chemical detection of hazardous substances in environmental and food samples has been addressed as well. To broaden the prospects of application, we have discussed the current challenges and future perspectives that would accelerate the development of versatile MIP-SERS chemical sensors.

3.
Food Chem ; 347: 129024, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33461115

RESUMO

Herein, a novel visual method for detecting triazophos based on competitive bio-barcode immunoassay was described. The competitive immunoassay was established by gold nanoparticles (AuNPs), magnetic microparticle (MMPs) and triazophos, combined with biochip hybridization system to detect the residual of triazophos in water and apple. Because AuNPs carried many bio-barcodes, which hybridized with labeled DNA on the biochip, catalyzed signal amplification using silver staining was detected by grayscale values as well as the naked eye. Notably, the grayscale values decreases with increasing the concentrations of triazophos, and the color change weakened gradually. The detection range was in between 0.05 and 10 ng/mL and the minimum detection limit was set at 0.04 ng/mL. Percent recovery calculated from spiked water and apple samples ranged between 55.4 and 107.8% with relative standard deviations (RSDs) of 12.4-24.9%. It has therefore been shown that this protocol provides a new insight for rapid detection of small molecule pesticides in various matrices.

4.
Int J Biol Macromol ; 172: 483-489, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33460654

RESUMO

Herein, the synthetic mechanism of octenyl succinic anhydride (OSA) modified corn starch (OSCS) and granule shells (OSCs) based on shells separation pretreatment (SSP) was investigated. High intensity peaks around 1720 and 1570 cm-1 were observed for OSCs in Fourier transform infrared (FTIR) spectra after SSP. OSCs showed higher degree of substitution (DS) values (ranging from 0.128 to 0.170) than OSCS (0.121) determined by 1H NMR. The average molecular weight (Mw) of OSA modified CS decreased, due to the introduction of OS groups. X-ray diffraction (XRD) indicated that esterification mainly took place in the amorphous regions of starch granules. X-ray photoelectron spectroscopy (XPS) revealed that a new peak corresponding to 1s orbital electrons of Na was obtained due to the introduction of OSA molecules. Meanwhile, lower surface DS and higher fluorescence intensity were noticed for OSCs. Conclusively, SSP would significantly increase the reaction efficiency of OSA modification process of CS.

5.
Crit Rev Food Sci Nutr ; : 1-11, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33401939

RESUMO

With increasing awareness of environmental protection, petroleum-based raw materials are continuously decreasing, which in turn necessitated the development of eco-friendly sustainable biomaterials, as alternative strategy. Starch could be an ideal substitute. Corn starch has been used as a renewable material for development of biodegradable packaging, owing to great varieties, low cost, large-scale industrial production, and good films forming properties. Unfortunately, its poor mechanical and barrier properties have limited the application of starch-based films. Thence, plasticizers were added to overcome the aforementioned pitfalls and improve the films elongation, distribution, flexibility, elasticity, and rigidity. Addition of plasticizers can change the continuity and therefore would enhance the properties of corn starch-based films. While plasticization can improve the tensile strength and percent elongation, it can reduce the water resistance in prepared films. Herein, we focused on changes of starch granules during gelatinization process, types of biodegradable films, as well as the types of modified starch with plasticizers. Furthermore, the influence of plasticizers on corn starch-based films and the physicochemical properties of various types of corn starch-based films were also addressed.

6.
Food Chem ; 348: 129105, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33508596

RESUMO

Herein, an analytical method was developed for simultaneous determination of 12 anthelmintics (closantel, niclosamide, nitroxynil, rafoxanide, cymiazole, fluazuron, levamisole, morantel, praziquantel, pyrantel, thiophanate, and trichlorfon) in fishery products (eel, flatfish, and shrimp) using liquid-liquid extraction coupled with liquid chromatography-tandem mass spectrometry. A reversed-phase analytical column was then used to separate the analytes from various matrices. Linear matrix-matched calibration curves were generated with coefficients of determination ≥ 0.9935. Recovery rates at three spiking levels (5, 10, and 20 µg/kg) ranged between 61.58% and 119.37% with relative standard deviations ≤ 19.05%. Limits of detection were in the range of 0.3-1.6 µg/kg, whereas limits of quantification ranged between 1.0 and 5.0 µg/kg. The matrix effect was moderate with values ranging from -99.47% to 51.98%. Matrices procured from large markets tested negative for the 12 anthelmintics. The developed method proved amenable to real sample testing and can be used for simultaneous determination of target analytes in aquatic products.

7.
Carbohydr Polym ; 254: 117314, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357877

RESUMO

Herein, corn starch-based films were prepared by casting method and different concentrations of Zanthoxylum bungeanum essential oil (ZYO) were added to evaluate the morphological, optical, mechanical, and barrier properties of the resultant films. Additionally, structural analysis was carried out via atomic force microscopy and the antibacterial activities against Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes were assessed. We found that the elongation at break was significantly increased (P < 0.05), whereas tensile strength, moisture content, solubility in water, and water vapor permeability rate were significantly decreased (P < 0.05) in films incorporated with ZYO compared with oil-free films. Furthermore, incorporation of ZYO increased the opacity and decreased the gloss of films. Incorporation of ZYO appears to increase the surface roughness and the antibacterial activity of the films. In sum, ZYO can potentially be used in food packaging, particularly food intended to be protected from light and susceptible to spoilage by microorganisms.

8.
Food Chem ; 337: 127780, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799164

RESUMO

To determine malachite green (MG) and its major metabolite, leucomalachite green (LMG) residual levels in tilapia fish, chemiluminescent enzyme immunoassay (CLEIA) was developed based on a single-chain variable fragment (scFv)-alkaline phosphatase (AP) fusion protein. At first, VH and VL gene sequences were cloned from hybridoma cell lines secreting monoclonal antibody against LMG, and then thoroughly by database-assisted sequence analysis. Finally, the productive VH and VL were assembled to an intact scFv sequence and engineered to produce scFv-AP fusion protein. The fusion protein was further identified as a bifunctional reagent for immunoassay, then a sensitive one-step CLEIA against LMG was developed with a half-maximal inhibitory concentration (IC50) and limit of detection (LOD) of 1.3 and 0.04 ng/mL, respectively. The validation results of this novel competitive CLEIA was in line with those obtained by classical HPLC method for determination of total MG in spiked and field incurred samples.


Assuntos
Produtos Pesqueiros/análise , Técnicas Imunoenzimáticas/métodos , Corantes de Rosanilina/análise , Tilápia , Fosfatase Alcalina/genética , Animais , Anticorpos Monoclonais , Resíduos de Drogas/análise , Hibridomas , Luminescência , Proteínas Recombinantes de Fusão , Anticorpos de Cadeia Única/genética
9.
J Cell Physiol ; 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33283879

RESUMO

Endoplasmic reticulum (ER) stress plays a causative role in the development of nonalcoholic fatty liver disease (NAFLD). Kynurenic acid (KA) is a tryptophan metabolite that has been shown to exert anti-inflammatory effects in macrophages and endothelial cells. However, the role of KA in ER stress-associated development of NAFLD has not been fully explored. In the current study, we observed decreased KA levels in the serum of obese subjects. Treated hepatocytes with KA attenuated palmitate-induced lipid accumulation and downregulated lipogenesis-associated genes as well as ER stress markers in a dose-dependent manner. Furthermore, KA augmented AMP-activated protein kinase (AMPK) phosphorylation, oxygen-regulated protein 150 (ORP150) expression, and autophagy markers. The small interfering RNA-mediated suppression of AMPK and ORP150, or 3-methyladenine also abrogated the effects of KA on ER stress and lipid accumulation in hepatocytes. In accordance with in vitro observations, KA administration to mice fed a high-fat diet ameliorated hepatic lipid accumulation and decreased the expression of lipogenic genes as well as ER stress. Moreover, KA treatment increased hepatic AMPK phosphorylation, ORP150 expression, and autophagy related markers in mouse livers. Knockdown of AMPK using in vivo transfection mitigated the effects of KA on hepatic steatosis and ER stress as well as autophagy and ORP150 expression. These results suggest that KA ameliorates hepatic steatosis via the AMPK/autophagy- and AMPK/ORP150-mediated suppression of ER stress. In sum, KA might be used as a promising therapeutic agent for treatment of NAFLD.

10.
Int J Biol Macromol ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33157138

RESUMO

Herein, the formation of starch-lipid complexes in steamed bread (SBr) free from and supplemented with fatty acids of varying chain lengths, including lauric acid (LA), glycerol monolaurate (GML), stearic acid (SA), and glycerol monostearate (GMS) and their effects on in vitro enzymatic digestibility were investigated. The enthalpy value of SBr samples (1.86-3.46 J/g) was significantly decreased (P < 0.05) compared to wheat starch samples (5.64-7.17 J/g) fortified with fatty acids. The relative crystallinity (16.5%-32.8%) of SBr corresponds to the content of starch-lipid complexes. SBr supplemented with fatty acids exhibited softer texture than lipid-free SBr stored at 4 °C for 0, 1, 4, and 7 days. Higher enzyme resistance was observed in SBr samples supplemented with fatty acids and the content of resistant starch (RS) was increased from 7.54% to 23.13% in SBr supplemented with LA. As demonstrated by microscopic computed tomography (mCT), the crystalline structure of SBr samples supplemented with LA and GML have a higher density than SBr fortified with SA and GMS; the findings which are in line with thermal properties and X-ray diffraction analysis. In sum, the formation of starch-lipid complexes could be considered as a new way to improve the SBr textural features during storage.

11.
Crit Rev Food Sci Nutr ; : 1-13, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33146021

RESUMO

Rice by-products, generated through the milling processes, have recently been recognized as a potential source of bioactive compounds, such as proteins, essential amino acids, and phenolics. Owing to their antioxidant capacity (which improve the storage stability of foods), these compounds have gained much attention because of their beneficial impacts on human health. It has to be noted that large quantities of rice by-products are not efficiently utilized, which may result in industrial wastes and environmental consequences. Thence, the aim of this review is to provide a comprehensive insight on the antioxidant capabilities, extraction, identification, functional attributes, and applications of bioactive hydrolysates and peptides derived from rice bran protein. This overview would provide an insight on rice bran proteins, which are abundant in bioactive peptides, and could be used as value-added products in food and pharmaceutical applications. Inclusion of bioactive peptides to prevent food spoilage while maintaining food safety has also been highlighted.

12.
Biomed Chromatogr ; : e5007, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067857

RESUMO

An analytical method was developed for the quantification of spinosad (sum of spinosyns A and D) in five animal-derived products (chicken breast, pork, beef, egg, and milk) using LC-MS/MS. The sample was extracted using acetonitrile/1% acetic acid and a combination of magnesium sulfate and sodium acetate salts. The sample was purified using multiwalled carbon nanotubes as sorbent via a dispersive-solid-phase extraction procedure. Matrix-matched calibration (seven-point) provided good linearity with coefficient of determination (R2 ) ≥0.99 for each product. The limits of detection and quantification (LOQs) ranged between 0.0003-0.03 and 0.001-0.1 mg/kg, respectively. Method validation was carried out after spiking the target standard to blank matrices at the concentration levels of LOQ, 2 × LOQ, and 10 × LOQ with three replicates for each. The average recoveries were between 74 and 104%, with relative standard deviations ≤9.68, which were within the acceptable range designated by the international organizations. The developed method was successfully applied for monitoring market samples collected throughout the Korean Peninsula, and none of the samples tested positive for the target analytes. It has therefore been shown that dehydration and acidification were effective to extract spinosad from animal-derived products.

13.
Adipocyte ; 9(1): 576-586, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32954935

RESUMO

Regular exercise is the first line of therapy for treating obesity-mediated metabolic disorders, including insulin resistance. It has been reported that developmental endothelial locus-1 (DEL-1) enhances macrophage efferocytosis, resulting in inflammation clearance as well as improves insulin resistance in skeletal muscle. However, the relationship between exercise and DEL-1, and the effects of DEL-1 on insulin signalling in adipocytes have not been fully elucidated to date. Protein expression levels were determined by Western blot analysis. Cells were transfected with small interfering (si) RNA to suppress gene expression. Lipid accumulation levels were detected using Oil red-O staining. Proinflammatory cytokine secretion levels were measured using ELISA. DEL-1 expression levels were induced in the skeletal muscle of people who exercised using microarray analysis. Recombinant DEL-1 augmented AMP-activated protein kinase (AMPK) phosphorylation and haem oxygenase (HO)-1 expression to alleviating inflammation and impairment of insulin signalling in 3T3-L1 adipocytes treated with palmitate. siRNA of AMPK or HO-1 also mitigated the effects of DEL-1 on inflammation and insulin resistance. DEL-1 ameliorates inflammation and insulin resistance in differentiated 3T3-L1 cells via AMPK/HO-1 signalling, suggesting that DEL-1 may be the exercise-mediated therapeutic target for treating insulin resistance and type 2 diabetes.

14.
Pharmaceutics ; 12(8)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785038

RESUMO

This study aimed to restore the skin barrier function from atopic dermatitis (AD) via treatment with leucine-rich glioma inactivated 3 (LGI3) peptide. Male NC/Nga mice (7 weeks, 20 g) were randomly allocated into three groups (control, AD, and LGI3 group). After induction of AD skin lesions with Dermatophagoides farinae ointment, mice were treated with LGI3. The clinical score of AD was the highest and the dorsal skin thickness was the thickest in the AD group. In contrast, LGI3 treatment improved the clinical score and the dorsal skin thickness compared to the AD model. LGI3 treatment suppressed histopathological thickness of the epithelial cell layer of the dorsal skin. LGI3 treatment could indirectly reduce mast cell infiltration through restoring the barrier function of the skin. Additionally, the filaggrin expression was increased in immunohistochemical evaluation. In conclusion, the ameliorating effect and maintaining skin barrier homeostasis in the AD murine model treated with LGI3 could be attributed to complete re-epithelialization of keratinocytes. Hence, LGI3 might be considered as a new potential therapeutic target for restoring skin barrier function in AD.

15.
Mol Cell Endocrinol ; 518: 110928, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32702471

RESUMO

Kynurenic acid (KA), an endogenous product of L-tryptophan metabolism in the kynurenine pathway, regulates adipose tissue energy homeostasis and inflammation. However, its role in palmitate-induced insulin resistance and detailed underlying mechanisms in skeletal muscles and adipose tissues are unclear. Herein, we report that KA ameliorated palmitate-induced inflammation and insulin resistance in differentiated C2C12 and 3T3-L1 cell lines as well as soleus skeletal muscle and subcutaneous adipose tissues in mice. Palmitate-induced inflammatory markers, such as nuclear factor κB translocation, inhibitory κBα phosphorylation, pro-inflammatory cytokine expression, and impaired insulin signaling, were markedly attenuated by KA both in vitro and in vivo. KA significantly increased AMP-activated protein kinase (AMPK) phosphorylation and sirtuin 6 (SIRT6) expressions in C2C12 myocytes and 3T3-L1 adipocytes and skeletal muscle and adipose tissues of mice. siRNA-mediated AMPK or SIRT6 inhibition significantly mitigated the suppressive effects of KA on palmitate-induced inflammation and insulin resistance. KA significantly stimulated expression of genes involved in fatty acid oxidation in C2C12 myocytes and skeletal muscle of mice. Moreover, KA inhibits lipogenesis in 3T3-L1 adipocytes. AMPK or SIRT6 siRNA markedly reversed these changes. The siRNA targeting Gpr35 abrogated the effects of KA on AMPK phosphorylation in C2C12 myocytes and 3T3-L1 adipocytes, except SIRT6 expression. It has therefore been shown that KA could potentially alleviate inflammation and insulin resistance in skeletal muscle and adipose tissues through Gpr35/AMPK and SIRT6-mediated pathways.

16.
J Agric Food Chem ; 68(28): 7298-7315, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32551623

RESUMO

Acetylcholinesterase inactivating compounds, such as organophosphate (OP) and carbamate (CM) pesticides, are widely used in agriculture to ensure sustainable production of food and feed. As a consequence of their applications, they would result in neurotoxicity, even death. In this essence, the development of enzyme inhibition methods still shows great significance as rapid detection techniques for on-site large-scale screening of OPs and CMs. Initially, mechanisms and applications of various enzyme-inhibition-based methods and devices, including optical colorimetric assay, fluorometric assays, electrochemical biosensors, rapid test card, and microfluidic device, are highlighted in the present overview. Further, to enhance the enzyme sensitivity for detection; alternative enzyme sources or high yield enrichment methods (such as abzyme, artificial enzyme, and recombinant enzyme), as well as enzyme reactivation and identification, are also addressed in this comprehensive overview.

17.
Mini Rev Med Chem ; 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32552643

RESUMO

Phytolacca dodecandra L'Herit (Endod) is the most extensively studied plant among 35 known species in the genus Phytolacca (Family: Phytolaccaceae). The plant has been used as a viable treatment for various ailments, such as malaria, rabies, ascariasis, and skin disorders, in many parts of Africa. In Ethiopia, the dried and powdered Endod berries have been used for a long period of time as a detergent to clean clothes. Since the discovery of the molluscicidal activities of its berries more than five decades ago, P. dodecandra has been a research focus worldwide and several phytochemicals mainly of triterpenoids and saponins were reported. Additionally, various biological activities, including larvicidal, insecticidal, antibacterial, antifungal, and anti-inflammatory activities of its isolated compounds and crude extracts were investigated. Furthermore, some of the findings from pharmacological and phytochemical investigations were patented to be used in various medicinal formulations. The plant is still the subject of many investigations and hence, a thorough up-to-date review is required to provide comprehensive information needed for future exploitation of the plant. In this review, the phytochemical compositions and pharmacological activities are comprehensively addressed and discussed in details.

18.
Am J Chin Med ; 48(4): 967-985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431178

RESUMO

Inflammation and endoplasmic reticulum (ER) stress have been documented to contribute to the development of atherosclerosis. Ginsenoside Rb2 has been reported to exhibit antidiabetic effects. However, the effects of Rb2 on atherosclerotic responses such as inflammation and ER stress in endothelial cells and monocytes remain unclear. In this study, the expression of inflammation and ER stress markers was determined using a Western blotting method. Concentrations of tumor necrosis factor alpha (TNF[Formula: see text]) and monocyte chemoattractant protein-1 (MCP-1) in culture media were assessed by enzyme-linked immunosorbent assay (ELISA) and apoptosis was evaluated by a cell viability assay and a caspase-3 activity measurement kit. We found that exposure of HUVECs and THP-1 monocytes to Rb2 attenuated inflammation and ER stress, resulting in amelioration of apoptosis and THP-1 cell adhesion to HUVECs under lipopolysaccharide (LPS) condition. Increased AMPK phosphorylation and heme oxygenase (HO)-1 expression, including GPR120 expression were observed in Rb2-treated HUVECs and THP-1 monocytes. Downregulation of both, AMPK phosphorylation and HO-1expression rescued these observed changes. Furthermore, GPR120 siRNA mitigated Rb2-induced AMPK phosphorylation. These results suggest that Rb2 inhibits LPS-mediated apoptosis and THP-1 cell adhesion to HUVECs by GPR120/AMPK/HO-1-associated attenuating inflammation and ER stress. Therefore, Rb2 can be used as a potential therapeutic molecule for treatment of atherosclerosis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Aterosclerose/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Lipopolissacarídeos/efeitos adversos , Fitoterapia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Aterosclerose/induzido quimicamente , Aterosclerose/genética , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Fosforilação/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/metabolismo , Células THP-1 , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
19.
Food Chem ; 326: 126813, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32438234

RESUMO

Herein, we developed a multi-analyte fluorescence immunoassay for detection of three organophosphate pesticides (triazophos, parathion, and chlorpyrifos) in various agro-products (rice, wheat, cucumber, cabbage, and apple) using fluorescently labeled oligonucleotide and gold nanoparticle (AuNP) signal amplification technology. The AuNP probes for the three analytes were constructed by simultaneously modifying the corresponding antibodies and fluorescently labeled oligonucleotides on the probe surface. Three fluorophores (6-FAM, Cy3, and Texas red) with high fluorescence intensity and little overlap of excitation/emission wavelengths were selected. The method showed satisfactory linearity for triazophos, parathion, and chlorpyrifos in the ranges of 0.01-20, 0.05-50, and 0.5-1000 µg/L, respectively. For the 3 analytes, the limits of detection (LODs) were 0.007, 0.009, and 0.087 µg/L, respectively. The average recoveries were 77.7-113.6%, with relative standard deviations (RSDs) of 7.1-17.1% in various food matrices. The proposed method offers great potential in food safety surveillance, and could be used as well as a reference for multi-residue analysis of other small-molecule contaminants.


Assuntos
Ouro/química , Inseticidas/análise , Nanopartículas Metálicas/química , Oligonucleotídeos/química , Clorpirifos/análise , Fluorescência , Análise de Alimentos , Imunoensaio/métodos , Limite de Detecção , Organotiofosfatos/análise , Paration/análise , Praguicidas/análise , Triazóis/análise
20.
Mikrochim Acta ; 187(5): 279, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32314246

RESUMO

A "half" core-shell g-C3N4/Fe3O4@ZIF-8 nanohybrid, in which Fe3O4 and zeolite imidazolate framework-8 (ZIF-8) constructed the core-shell structure, was successfully fabricated via a versatile in situ growth strategy. This nanohybrid was employed for simultaneous magnetic solid-phase extraction (MSPE) of trace levels of fifteen target sulfonylurea herbicides (SUHs) in environmental water samples followed by LC-MS/MS detection. C3N4 nanosheets were first prepared by liquid exfoliation of bulk g-C3N4, after which Fe3O4 nanoparticles were uniformly deposited onto the surface of C3N4 nanosheets, and ZIF-8 nanoparticles were grown on the surface of g-C3N4/Fe3O4 by anchoring Zn2+ on g-C3N4/Fe3O4. Owing to the synergistic effect, the hybridization of C3N4 and ZIF-8 endowed the nanohybrid with higher multi-target adsorption ability for SUHs compared to pure C3N4 or ZIF-8. The separation as well as the enrichment processes were facilitated using Fe3O4 as a magnetic core. The influence of various parameters on MSPE efficiency, including adsorbent dosage, extraction time, solution pH, and desorption solvent and its volume, was investigated in detail. Under optimal conditions, the MSPE coupled with LC-MS/MS exhibited good linearity ranging from 0.5 to 100 µg L-1 with correlation coefficients (R2) ≥ 0.9919, high sensitivity with low limits of detection (LODs) of 0.005-0.141 µg L-1 and satisfactory recoveries of 67.4-105.5% with relative standard deviations (RSDs) < 9.8%. These results indicate that this method is reliable for the determination of SUHs in different matrices and the in situ growth strategy is a promising approach for constructing effective adsorbents. Graphical abstract Schematic representation of a "half" core-shell magnetic nanohybrid composed of zeolitic imidazolate framework (ZIF-8) and graphitic carbon nitride (g-C3N4) for magnetic solid-phase extraction (MSPE) of trace level determination of fifteen sulfonylurea herbicides (SUHs) in environmental water samples using LC-MS/MS detection.

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