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1.
Chembiochem ; 25(7): e202300742, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38426686

RESUMO

Pesticides are essential in agricultural development. Controlled-release pesticides have attracted great attentions. Base on a principle of spatiotemporal selectivity, we extended the photoremovable protective group (PRPG) into agrochemical agents to achieve controllable release of active ingredients. Herein, we obtained NP-TBZ by covalently linking o-nitrobenzyl (NP) with thiabendazole (TBZ). Compound NP-TBZ can be controlled to release TBZ in dependent to light. The irradiated and unirradiated NP-TBZ showed significant differences on fungicidal activities both in vitro and in vivo. In addition, the irradiated NP-TBZ displayed similar antifungal activities to the directly-used TBZ, indicating a factual applicability in controllable release of TBZ. Furthermore, we explored the action mode and microcosmic variations by SEM analysis, and demonstrated that the irradiated NP-TBZ retained a same action mode with TBZ against mycelia growth.


Assuntos
Praguicidas , Tiabendazol , Tiabendazol/farmacologia , Tiabendazol/análise , Preparações de Ação Retardada , Antifúngicos/farmacologia
2.
Anal Bioanal Chem ; 416(14): 3295-3303, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696128

RESUMO

Thiabendazole, a widely used broad-spectrum fungicide in agriculture, poses risks to human health. To monitor its presence in water, we propose a fluorescent aptasensor utilizing Escherichia coli exonuclease I (Exo I). The findings demonstrate a linear correlation between thiabendazole concentrations and digestion percentage, with a detection limit (LOD) exceeding 1 µM and a determination coefficient (R2) of 0.959. This aptamer-based fluorescence spectroscopy detection system holds promise for a rapid, specific, and sensitive analysis of thiabendazole in environmental waters and food matrices.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Limite de Detecção , Espectrometria de Fluorescência , Tiabendazol , Tiabendazol/análise , Aptâmeros de Nucleotídeos/química , Espectrometria de Fluorescência/métodos , Técnicas Biossensoriais/métodos , Fungicidas Industriais/análise , Exodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/química , Escherichia coli , Poluentes Químicos da Água/análise , Corantes Fluorescentes/química
3.
Anal Bioanal Chem ; 416(2): 497-508, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38001372

RESUMO

Pesticides that linger in the environment and ecosystems for an extended period can cause severe and dangerous health problems in humans. To detect pesticides in foods, the development of high-sensitivity and quick screening technologies was required. This research investigated the performance of Au@Ag NPs with varying thicknesses of the silver shell for detecting trace quantities of thiabendazole (TBZ) in apples using surface-enhanced Raman spectroscopy (SERS). The Au@Ag NPs were synthesized by coating 32 nm gold seeds with different thicknesses of silver shell ranging from 2.4 to 8.7 nm, achieved by adjusting the incorporation of AgNO3 and ascorbic acid. The optimized Au@Ag NPs with a 7.3 nm silver shell demonstrated outstanding SERS activity, high sensitivity, and a detection limit of 0.05 µg/mL for TBZ. The R2 values, representing the goodness of fit, were found to be 0.990 and 0.986 for standard and real TBZ samples, respectively, indicating a strong correlation between the measured signal and the TBZ concentration. The recovery analysis showed a reliable and accurate detection capability (96 to 105%), suggesting good reliability and accuracy of the SERS-based detection using the optimal Au@Ag NPs. Overall, this research highlights the potential of SERS with optimal Au@Ag NPs for rapid and effective monitoring of pesticides in the food industry.


Assuntos
Malus , Nanopartículas Metálicas , Praguicidas , Humanos , Malus/química , Tiabendazol/análise , Prata/química , Reprodutibilidade dos Testes , Ecossistema , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos , Praguicidas/análise , Ouro/química
4.
Molecules ; 29(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39124899

RESUMO

Anthelmintic resistance in gastrointestinal nematodes produces substantial challenges to agriculture, and new strategies for nematode control in livestock animals are called for. Natural compounds, including tannins, with proven anthelmintic activity could be a functional option as structurally diverse complementary compounds to be used alongside commercial anthelmintics. However, the dual use of two anthelmintic components requires an understanding of the pharmacological effects of the combination, while information concerning the interactions between plant-based polyphenols and commercial anthelmintics is scarce. We studied the direct interactions of proanthocyanidins (PAs, syn. condensed tannins) and a commercial anthelmintic thiabendazole, as a model substance of benzimidazoles, by isothermal titration calorimetry (ITC). Our results show evidence of a direct interaction of an exothermic nature with observed enthalpy changes ranging from 0 to -30 kJ/mol. The strength of the interaction between PAs and thiabendazole is mediated by structural characteristics of the PAs with the strongest positive correlation originating from the presence of galloyl groups and the increased degree of polymerization.


Assuntos
Anti-Helmínticos , Calorimetria , Proantocianidinas , Tiabendazol , Proantocianidinas/química , Proantocianidinas/farmacologia , Tiabendazol/química , Tiabendazol/farmacologia , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Termodinâmica , Animais
5.
J Sci Food Agric ; 104(5): 2630-2640, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37985216

RESUMO

BACKGROUND: Understanding the role of adjuvants in pesticide persistence is crucial to develop effective pesticide formulations and manage pesticide residues in fresh produce. This study investigated the impact of a commercial non-ionic surfactant product containing alkylphenol ethoxylates (APEOs) on the persistence of thiabendazole on apple and spinach surfaces against the 30 kg m-3 baking soda (sodium bicarbonate, NaHCO3 ) soaking, which was used to remove the active ingredient (AI) in the cuticular wax layer of fresh produce through alkaline hydrolysis. Surface-enhanced Raman scattering (SERS) mapping method was used to quantify the residue levels on fresh produce surfaces at different experimental scenarios. Four standard curves were established to quantify surface thiabendazole in the absence and presence of APEOs, on apple and spinach leaf surfaces, respectively. RESULTS: Overall, the result showed that APEOs enhanced the persistence of thiabendazole over time. After 3 days of exposure, APEOs increased thiabendazole surface residue against NaHCO3 hydrolysis on apple and spinach surfaces by 5.39% and 10.47%, respectively. CONCLUSION: The study suggests that APEOs led to more pesticide residues on fresh produce and greater difficulty in washing them off from the surfaces using baking soda, posing food safety concerns. © 2023 Society of Chemical Industry.


Assuntos
Malus , Resíduos de Praguicidas , Praguicidas , Malus/química , Resíduos de Praguicidas/análise , Praguicidas/análise , Bicarbonato de Sódio , Análise Espectral Raman/métodos , Spinacia oleracea/química , Tensoativos , Tiabendazol/análise , Fenóis/química
6.
J Fluoresc ; 33(4): 1577-1591, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36790630

RESUMO

A novel conjugated polymer PCZBTA-TBZ containing thiabendazole as recognition unit was synthesized via Suzuki coupling reaction, and its structural characterization, spectroscopic analysis and photophysical properties were investigated. In the metal ion response study, the addition of Cu2+ led to the occurrence of the photoinduced electron transfer (PET) mechanism, which significantly quenched the fluorescence of the polymer PCZBTA-TBZ with a quenching effect of 98%. Furthermore, I- can significantly quench the fluorescence of the polymer, but other anions have no such effect. According to the density functional theory calculation, compared with other polycarbazoles or other alternative copolymers containing carbazole, with alternating carbazole and triazole enhances the electron mobility and reduces the energy band gap of the polymer. Due to the strong coordination ability between Cu2+ and Cys, the adding Cys competes the Cu2+ in the [PCZBTA-TBZ-Cu2+] complex, blocking the occurrence of PET, and the fluorescence intensity of PCZBTA-TBZ is restored. The addition of other amino acids caused almost no change. The polymer is expected to be used for dual fluorescence detection of specific metal ions and Cys.

7.
Molecules ; 28(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37175335

RESUMO

Thiabendazole (TBZ) is a fungicide and anthelmintic drug commonly found in food products. Due to its toxicity and potential carcinogenicity, its determination in various samples is important for public health. Different analytical methods can be used to determine the presence and concentration of TBZ in samples. Liquid chromatography (LC) and its subtypes, high-performance liquid chromatography (HPLC) and ultra-high-performance liquid chromatography (UHPLC), are the most commonly used methods for TBZ determination representing 19%, 18%, and 18% of the described methods, respectively. Surface-enhanced Raman spectroscopy (SERS) and fluorimetry are two more methods widely used for TBZ determination, representing 13% and 12% of the described methods, respectively. In this review, a number of methods for TBZ determination are described, but due to their limitations, there is a high potential for the further improvement and development of each method in order to obtain a simple, precise, and accurate method that can be used for routine analysis.


Assuntos
Fungicidas Industriais , Tiabendazol , Tiabendazol/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Fungicidas Industriais/análise , Fluorometria
8.
Molecules ; 28(13)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37446937

RESUMO

Plant tannins are known for their anthelmintic and antiparasitic activities and have been increasingly studied to battle the ever-growing problem of anthelmintic resistance. While tannins have been shown to exhibit these activities on their own, one approach would be to use them as complementary nutrients alongside commercial anthelmintics. So far, research on the interactions between tannins and anthelmintics is limited, and few studies have reported both synergistic and antagonistic effects depending on the type of tannin and the method used. These interactions could either strengthen or weaken the efficacy of commercial anthelmintics, especially if tannin-rich diets are combined with anthelmintics used as oral drenches. To study these interactions, a series of hydrolysable tannins (HTs) was selected, and their direct interactions with thiabendazole (TBZ) were evaluated by isothermal titration calorimetry (ITC), which allowed the detection of the exothermic interaction but also the roles and significances of different structural features of HTs in these interactions. Our results show that HTs can have a direct interaction with the benzimidazole anthelmintic TBZ and that the interaction is strengthened by increasing the number of free galloyl groups and the overall molecular flexibility of HTs.


Assuntos
Anti-Helmínticos , Taninos , Taninos/farmacologia , Taninos/química , Anti-Helmínticos/química , Extratos Vegetais/química , Taninos Hidrolisáveis , Tiabendazol , Calorimetria/métodos
9.
Molecules ; 28(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894557

RESUMO

Ag nanoparticles sputtered on silicon wafer are used as masks for the fabrication of silicon columns by ion etching, which induces the growth of the inclined Ag nanorod by inclined Ag sputtering. V-shaped and Z-shaped Ag nanorods can be obtained by varying incline angles and deposition times. SERS detection and FDTD simulation are used to compare and investigate the enhanced electromagnetic coupling of incline nanorod arrays with different shapes in three-dimensional space, which indicates that Z-shaped nanorods show good SERS properties. The Z-shaped Ag nanorod array is used as a SERS substrate for the detection of thiabendazole with a concentration down to 10-11 M.

10.
Sensors (Basel) ; 22(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35632191

RESUMO

Direct potentiometric measurements using solid-state sensors have a great potential for thiabendazole (TBZ) determination, considering simplicity, accuracy, and low cost. Modifying the sensing material of the sensor with multi-walled carbon nanotubes (MWCNTs) leads to improved analytical properties of the sensor. In this study, a new potentiometric solid-state sensor for TBZ determination, based on MWCNTs modified with a sulfate group, and TBZ ion as sensing material was developed. The sensor exhibited a Nernstian response for TBZ (60.4 mV/decade of activity) in a working range between 8.6 × 10-7 and 1.0 × 10-3 M. The detection limit for TBZ was 6.2 × 10-7 M. The response time of the sensor for TBZ was 8 s, and its signal drift was only 1.7 mV/h. The new sensor is applicable for direct potentiometric determination of TBZ in complex real samples, such as fruit peel. The accuracy of TBZ determination is confirmed using the standard addition method.


Assuntos
Nanotubos de Carbono , Materiais Inteligentes , Eletrodos , Potenciometria , Tiabendazol
11.
Sensors (Basel) ; 22(24)2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36560348

RESUMO

Rapid analysis of components in complex matrices has always been a major challenge in constructing sensing methods, especially concerning time and cost. The detection of pesticide residues is an important task in food safety monitoring, which needs efficient methods. Here, we constructed a machine learning-assisted synchronous fluorescence sensing approach for the rapid and simultaneous quantitative detection of two important benzimidazole pesticides, thiabendazole (TBZ) and fuberidazole (FBZ), in red wine. First, fluorescence spectra data were collected using a second derivative constant-energy synchronous fluorescence sensor. Next, we established a prediction model through the machine learning approach. With this approach, the recovery rate of TBZ and FBZ detection of pesticide residues in red wine was 101% ± 5% and 101% ± 15%, respectively, without resorting complicated pretreatment procedures. This work provides a new way for the combination of machine learning and fluorescence techniques to solve the complexity in multi-component analysis in practical applications.


Assuntos
Resíduos de Praguicidas , Vinho , Tiabendazol/análise , Resíduos de Praguicidas/análise , Vinho/análise , Fluorescência , Benzimidazóis
12.
Molecules ; 27(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35630618

RESUMO

In many regions of the world, Leishmaniasis is a cause of substantial mortality and ailment. Due to impediment in available treatment, development of novel and effective treatments is indispensable. Significance of autophagy has been accentuated in infectious disease as well as in Leishmaniasis, and it is having capability to be manifested as a therapeutic target. By evincing autophagy as a novel therapeutic regime, this study emphasized on the critical role of ATG4.1-ATG8 and ATG5-ATG12 complexes in Leishmania species. The objective here was to identify ATG8 as a potential therapeutic target in Leishmania. R71T, P56E, R18P are the significant mutations which shows detrimental effect on ATG8 while Arg276, Arg73, Cys75 of ATG4.1 and Val88, Pro89, Glu116, Asn117, and Gly120 are interacting residues of ATG8. Along with this, we also bring into spotlight an enticing role of Thiabendazole derivatives that interferes with the survival mechanisms by targeting ATG8. Further, the study claims that thiabendazole can be a potential drug candidate to target autophagy process in the infectious disease Leishmaniasis.


Assuntos
Doenças Transmissíveis , Leishmania , Leishmaniose , Autofagia/genética , Humanos , Leishmaniose/tratamento farmacológico , Tiabendazol
13.
Trop Med Int Health ; 26(11): 1419-1426, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34370367

RESUMO

OBJECTIVES: Human toxocariasis is a widespread zoonosis for which a chemotherapy decision and therapy effectiveness are difficult to determine. We aimed to investigate the kinetic profile of clinical and laboratory findings and treatment outcome of patients with toxocariasis in Vietnam. METHODS: The prospective study was conducted between October 2017 and June 2019. The diagnosis of toxocariasis was established based on clinical, laboratory (eosinophilia, raised IgE concentration) and serological (positive Toxocara IgG ELISA) evaluation as well as the exclusion of another helminthic co-infection. The patients were followed up after seven days, then one, three and six months after chemotherapy by thiabendazole. RESULTS: The study involved 80 patients with a mean age of 41.6 ± 15.2 years of whom 58.8% were female. At three and six months after chemotherapy, most patients demonstrated resolution of clinical signs and symptoms, eosinophil count and IgE concentration but not in the proportion of IgG seropositivity. Skin lesions and eosinophilia resolved earlier than the other symptoms (one month after treatment). About four-fifths of the patients were "cured" after three and six months of follow-up; 33.8% showed side effects to thiabendazole therapy but no severe events were reported. The most common adverse reaction was neurologic symptoms followed by gastrointestinal or skin manifestations which lasted as long as 4 days. CONCLUSIONS: In toxocariasis patients, cutaneous manifestations and eosinophilia resolve more rapidly than other clinical and laboratory findings while IgG titre has a very slow kinetic after therapy. Thiabendazole seems to be a potential alternative for the treatment of human toxocariasis.


Assuntos
Toxocaríase/diagnóstico , Adolescente , Adulto , Idoso , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/uso terapêutico , Anticorpos Anti-Helmínticos/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tiabendazol/administração & dosagem , Tiabendazol/uso terapêutico , Toxocara/imunologia , Toxocaríase/sangue , Toxocaríase/tratamento farmacológico , Toxocaríase/epidemiologia , Vietnã/epidemiologia , Adulto Jovem , Zoonoses/diagnóstico , Zoonoses/tratamento farmacológico
14.
Sud Med Ekspert ; 64(3): 34-40, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34013693

RESUMO

OBJECTIVE: Is to study the features and to develop the methods for the determination of thiabendazole in the tissues of cadaveric organs and blood. When performing the experiments the methods of TLC, GC-MS and spectrophotometry were used. The advantages were substantiated and the optimal conditions for the release of thiabendazole from the tissues of organs and blood with acetone were determined. A variant of purification of the substance extracted from biomatrixes by the method of column chromatography of normal pressure (sorbent L 40/100 µm, mobile phase acetone-dichloromethane (9.5: 0.5)) is proposed. To identify the analyte by TLC the Sorbfil plates were used and a toluene-acetonitrile mobile phase (2:8). When identifying thiabendazole by a combination of gas-liquid chromatography and mass spectrometry (fragmentation of molecules by electron impact 70 eV) an HP-5MS column 30 m × 0.25 mm with a non-polar stationary phase (5% -phenyl) -methylpolysiloxane was proposed. The expediency of the spectrophotometric determination of thiabendazole on the basis of absorption in an acetonitrile medium has been shown. Methods for the determination of thiabendazole in tissues of organs and blood have been developed and validated. It is shown that the techniques meet the requirements of linearity, selectivity, correctness, precision and stability. The limits of detection of thiabendazole in the liver and blood are 0.14 and 0.10 mg, respectively; the limits of quantitative determination are 0.26 and 0.18 mg per 100 g of biomatrix.


Assuntos
Materiais Biocompatíveis , Tiabendazol , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectrometria de Massas , Espectrofotometria , Tiabendazol/análise , Tiabendazol/toxicidade
15.
J Biol Inorg Chem ; 25(8): 1067-1083, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32951085

RESUMO

The synthesis and characterization of two half-sandwich complexes of Ru(II) and Ir(III) with thiabendazole as ancillary ligand and their DNA binding ability were investigated using experimental and computational methods. 1H NMR and acid-base studies have shown that aquo-complexes are the reactive species. Kinetic studies show that both complexes bind covalently to DNA through the metal site and non covalently through the ancillary ligand. Thermal stability studies, viscosity, circular dichroism measurements and quantum chemical calculations have shown that the covalent binding causes breaking of the H-bonding between base pairs, bringing about DNA denaturation and compaction. Additionally, molecular dynamics (MD) simulations and quantum mechanics/molecular mechanics (QM/MM) calculations shed light into the binding features of the Ru(II) and Ir(III) complexes and their respective enantiomers toward double-helical DNA, highlighting the important role played by the NˆN ancillary ligand once the complexes are covalently linked to DNA. Moreover, metal quantification in the nucleus of SW480 colon adenocarcinoma cells were carried out by inductively coupled plasma-mass spectrometry (ICP-MS), both complexes are more internalized than cisplatin after 4 h of exposition. However, in spite of the dramatic changes in the helicity of the DNA secondary structure induced by these complexes and their nuclear localization, antiproliferative studies have revealed that both, Ru(II) and Ir(III) complexes, cannot be considered cytotoxic. This unexpected behavior can be justified by the fast formation of aquo-complexes, which may react with components of the cell culture medium or the cytoplasm compartment in such a way that they may become deactivated before reaching DNA.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , DNA/química , Irídio/química , Simulação de Dinâmica Molecular , Rutênio/química , Tiabendazol/química , Complexos de Coordenação/metabolismo , DNA/metabolismo , Conformação de Ácido Nucleico
16.
J Sep Sci ; 43(14): 2842-2849, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32320521

RESUMO

In this study, the new and efficient three-dimensional network porous aromatic frameworks materials called Silica-PAFs-a, Florisil-PAFs-a, Silica-PAFs-b, and Florisil-PAFs-b were first synthesized. The properties of materials were analyzed by five characterization methods. The materials were used as adsorbents in pipette-tip solid-phase extraction for the effective determination of carbendazim and thiabendazole in spinach sample. Meanwhile, the obtained materials were tested by static adsorption and dynamic adsorption. The result showed that the specific surface area of materials greatly increased after introducing three-dimensional network porous aromatic frameworks. Microstructural modification exposed a large number of amino reactive groups that made them have a better adsorption amount for the two targets. The calibration graphs of carbendazim and thiabendazole in methanol were linear over 0.10-300.0 µg/mL, and the limits of detection and quantification were 0.00546 and 0.0182 µg/mL, and 0.00741 and 0.0247µg/mL respectively. A reliable analytical method was developed for recognition targets in spinach sample by Silica-PAFs-b with satisfactory extraction recoveries (96.25 and 100.51%). The proposed method using the material was applied for trace analysis of the carbendazim and thiabendazole residue.


Assuntos
Benzimidazóis/análise , Carbamatos/análise , Hidrocarbonetos Aromáticos/química , Spinacia oleracea/química , Tiabendazol/análise , Triazinas/química , Hidrocarbonetos Aromáticos/síntese química , Silicatos de Magnésio/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Dióxido de Silício/química , Propriedades de Superfície
17.
Molecules ; 25(13)2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32640762

RESUMO

Thiabendazole (TBZ) is a substance which has been receiving multiple important applications in several domains, from medicine and pharmaceutical sciences, to agriculture and food industry. Here, a comprehensive multi-technique investigation on the molecular and crystal properties of TBZ is reported. In addition, a new solvate of the compound is described and characterized structurally, vibrationally and thermochemically for the first time. Density functional theory (DFT) calculations were used to investigate the conformational space of thiabendazole (TBZ), revealing the existence of two conformers, the most stable planar trans form and a double-degenerated-by-symmetry gauche form, which is ~30 kJ mol-1 higher in energy than the trans conformer. The intramolecular interactions playing the major roles in determining the structure of the TBZ molecule and its conformational preferences were characterized. The UV-visible and infrared spectra of the isolated molecule (most stable trans conformer) were also calculated, and their assignment undertaken. The information obtained for the isolated molecule provided a strong basis for the understanding of the intermolecular interactions and properties of the crystalline compound. In particular, the infrared spectrum for the isolated molecule was compared with that of crystalline TBZ and the differences between the two spectra were interpreted in terms of the major intermolecular interactions existing in the solid state. The analysis of the infrared spectral data was complemented with vibrational results of up-to-date fully-periodic DFT calculations and Raman spectroscopic studies. The thermal behavior of TBZ was also investigated using differential scanning calorimetry (DSC) and thermogravimetry. Furthermore, a new TBZ-formic acid solvate [2-(1,3-thiazol-4-yl)benzimidazolium formate formic acid solvate] was synthesized and its crystal structure determined by X-ray diffraction. The Hirshfeld method was used to explore the intermolecular interactions in the crystal of the new TBZ solvate, comparing them with those present in the neat TBZ crystal. Raman spectroscopy and DSC studies were also carried out on the solvate to further characterize this species and investigate its temperature-induced desolvation.


Assuntos
Formiatos/química , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos , Termogravimetria/métodos , Tiabendazol/química , Varredura Diferencial de Calorimetria , Química Computacional , Isomerismo , Conformação Molecular , Solventes/química , Temperatura , Vibração , Difração de Raios X
18.
J Sep Sci ; 42(9): 1786-1793, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30805997

RESUMO

A new sample preparation method based on SBA-15 assisted electromembrane extraction coupled with corona discharge ion mobility spectrometer was developed for the determination of Thiabendazole as a model basic pesticide in fruit juice samples. The addition of SBA-15 in the supported liquid membrane in electromembrane extraction system not only can lead to enhancement of the effective surface area, but also introducing the negatively charged silanol groups into supported liquid membrane might improve migration of positively charged analytes toward the supported liquid membrane and finally into the acceptor solution. To investigate the effect of the presence of SBA-15 in the supported liquid membrane on the extraction efficiency, a comparative study was carried out between the conventional electromembrane extraction and SBA-15/electromembrane extraction methods. Under the optimized conditions, SBA-15/electromembrane extraction method showed higher extraction efficiencies in comparison with conventional electromembrane extraction method. SBA-15/electromembrane extraction method exhibited a low limit of detection (0.9 ng/mL), high preconcentration factor (167) and high recovery (83%). Finally, the applicability of SBA-15/electromembrane extraction method was studied by the extraction and determination of Thiabendazole as a model basic pesticide in fruit juice samples.


Assuntos
Técnicas Eletroquímicas/métodos , Sucos de Frutas e Vegetais/análise , Praguicidas/isolamento & purificação , Tiabendazol/isolamento & purificação , Animais , Técnicas Eletroquímicas/instrumentação , Limite de Detecção , Membranas Artificiais , Praguicidas/análise , Dióxido de Silício/química , Tiabendazol/análise
19.
Mikrochim Acta ; 186(9): 603, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31385118

RESUMO

A flexible adhesive tape decorated with SERS-active silver nanorods (AgNRs) in the form of an array nanostructure is described. The tape was constructed by transferring the AgNRs nanostructures from silicon to the transparent tape by a "paste & peel off" procedure. The transparent, sticky, and flexible properties of commercial tapes allow almost any SERS-inactive irregular surface to be detected in-situ by pasting the SERS tape onto the position to be analyzed. Three examples for an analytical application are presented, viz. determination of (a) tetramethylthiuram disulfide and thiabendazole (two pesticides), (b) colorants in the gel of a writing pen, and (c) the fluorophore Rhodamine B. The tetramethylthiuram disulfide on apple surface was rapidly detected with a LOD of 28.8 ng·cm-2. The AgNRs effectively quenched the fluorescence of the matrix and fluorophores, this enabling the colorants and Rhodamine B to be identified. The results demonstrated that the SERS tape can be used for versatile in-situ detection. Conceivably, it may find applications in food analysis, non-invasive identification, environmental monitoring, and in other areas of daily life. Graphic abstract A flexible and adhesive SERS active tape decorated with silver nanorods (AgNRs) arrays was constructed through a "paste & peel off" method. It can be used as a versatile in situ analysis platform for various applications.

20.
Anal Bioanal Chem ; 410(26): 6923-6934, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30094787

RESUMO

Fluorescence polarization immunoassays (FPIAs) for thiabendazole and tetraconazole were first developed. Tracers for FPIAs of thiabendazole and tetraconazole were synthesized and the tracers' structures were confirmed by HPLC-MS/MS. The 4-aminomethylfluorescein-labeled tracers allowed achieving the best assay sensitivity and minimum reagent consumption in comparison with aminofluorescein-labeled and alkyldiaminefluoresceinthiocarbamyl-labeled tracers. Measurements of fluorescence polarization were performed using a portable device. The developed FPIA methods were applied for the analysis of wheat. Fast and simple sample preparation technique earlier developed by authors for pesticides was adapted for thiabendazole and tetraconazole. The limits of detection of thiabendazole and tetraconazole in wheat were 20 and 200 µg/kg, and the lower limits of quantification were 40 and 600 µg/kg, respectively. The recovery test was performed by two methods-FPIA and HPLC-MS/MS. The results obtained by FPIA correlated well with those obtained by HPLC-MS/MS (r2 = 0.9985 for thiabendazole, r2 = 0.9952 for tetraconazole). Average recoveries of thiabendazole and tetraconazole were 74 ± 4% and 72 ± 3% by FPIA, and average recoveries of thiabendazole and tetraconazole were 86 ± 2% and 74 ± 1% by HPLC-MS/MS (n = 15). Graphical abstract ᅟ.


Assuntos
Anti-Helmínticos/análise , Clorobenzenos/análise , Imunoensaio de Fluorescência por Polarização/métodos , Fungicidas Industriais/análise , Praguicidas/análise , Tiabendazol/análise , Triazóis/análise , Triticum/química , Cromatografia Líquida de Alta Pressão/métodos , Indicadores e Reagentes/química , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
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