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1.
Phys Chem Chem Phys ; 26(27): 18997-19007, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38953750

RESUMO

N-((Bis(dimethyl amino)methylene)carbamothioyl)benzamide (NBMCB) was synthesized, characterized, and used as an ionophore for producing three novel ion-selective potentiometric sensors for Fe(III) determination. Firstly, using the molecular mechanic-based MMFF94 method, the most stable NBMCB's conformer and its isosteric complexes with various cations were determined. According to the Gibbs free energy results of the reaction, the thermodynamic complexation reactivity of Fe(III) and the ligand was acceptable. These results were obtained using the B3LYP approach and the 6-31G(d,p) basis set that was substituted for heavy metals by the LanL2DZ basis set. We used UV-visible spectrophotometry to confirm the tendency of NBMCB to react with Fe(III). Generally, three diverse liquid membrane ferric selective electrodes were obtained by the use of the specified ligand: classic with a liquid internal electrolyte-ferric selective electrode (LIE-FSE), solid state-FSE (SS-FSE), and coated wire-FSE (CW-FSE). The reactions exhibited Nernstian behavior across all electrodes. The limit of detection was enhanced for the SS-FSE (3 × 10-9 M) and the CW-FSE (3 × 10-7 M) in comparison with that of the LIE-FSE (7 × 10-7 M). The lifetime of the LIE-FSE was 8 weeks, while it was 10 weeks for the SS-FSE and the CW-FSE. Elimination of the internal solution reduced the limit of detection and prolonged the lifespan of the sensors. Also, the three electrodes all had a short response time of around 5-7 s. The sensors were utilized as indicator electrodes during the potentiometric titration of Fe(III) using ethylenediaminetetraacetic acid.

2.
Heliyon ; 10(3): e24771, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322939

RESUMO

A novel and efficient bionanocomposite was synthesized by incorporating SnO into chitosan (Ch) and a room-temperature ionic liquid (RTIL). The bionanocomposite was synthesized in benzoyl pyridinium chloride [BzPy]Cl to maintain the unique properties of SnO, chitosan, and the ionic liquid. Adsorption and photodegradation processes were applied to evaluate the bionanocomposite for removing azo and anthraquinone dyes and textile wastewater. SnO/[BzPy]Cl and SnO/[BzPy]Cl/Ch samples were prepared and characterized using various techniques, including FT-IR, SEM, XRD, EDAX, XPS, DSC, TGA, nitrogen adsorption/desorption isotherm, and DRS analysis. SEM analysis revealed a hierarchical roughened rose flower-like morphology for the biocomposite. The band gap energies of SnO/[BzPy]Cl and SnO/[BzPy]Cl/chitosan were found to be 3.9 and 3.3 eV, respectively, indicating a reduction in the band gap energy with the introduction of [BzPy]Cl and chitosan. SnO/[BzPy]Cl/Ch showed high removal rates (92-95 %) for Fast Red, Blue 15, Red 120, Blue 94, Yellow 160, and Acid Orange 7 dyes. The adsorption kinetics followed a pseudo-second-order model. In addition, the effect of different photodegradation parameters such as solution pH, dye concentrations, contact time, and amount of photocatalyst, was studied. Given the optimal results obtained in removing azo and anthraquinone dyes, the SnO/[BzPy]Cl/Ch nanocomposite was used as an efficient nanocomposite for removing dyes from textile wastewater. The highest removal efficiency was found to be 95.8 %, obtained under ultraviolet and visible light. Furthermore, BOD and COD reduction analysis showed significant reductions, indicating the excellent performance of the photocatalyst.

3.
Heliyon ; 9(12): e22842, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125423

RESUMO

In the present paper, three electrodes were prepared with the aim of detecting chromium (III) in pharmaceutical tablets and comparing their capabilities and efficiency. At first, N-(pyridine-2-ylcarbamothioyl) benzamide (NP2YCTB) was synthesized and characterized by 1H NMR, FTIR, and 13C NMR spectroscopy methods. Then, it is used as a sensing material to prepare three types of chromium potentiometry sensors including solid-state electrodes (SSE), coated wire electrodes (CWE) as asymmetric electrodes, and liquid membrane electrodes (LME) as symmetric electrodes. The responses of all electrodes were Nernstian. Field-emission scanning electron microscopy was utilized to investigate the liquid membrane morphology. The presence of chromium (III) in the membrane was proved using Energy-dispersive X-ray spectroscopy and the coordination of NP2YCTB heteroatoms with chromium (III) was confirmed by Fourier transform infrared spectroscopy. The limit of detection for SSE (3 × 10-9 mol/L) was enhanced compared with LME (7 × 10-6 mol/L) and CWE (3 × 10-7 mol/L). The response time of electrodes was very short so it was about 5-6 s for LME and CWE and 5-8 s for SSE. The sensors were used for the potentiometric determination of chromium (III) in pharmaceutical tablets and in the potentiometric titration of it with EDTA.

4.
Int J Biol Macromol ; 234: 123660, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796564

RESUMO

Ionogels are a category of hybrid material containing ionic liquid stabilized by polymeric network. These composites have some applications in solid-state, energy storage devices and environmental studies. In this research, chitosan (CS), ethyl pyridinium iodide ionic liquid (IL), and ionogel (IG) consisting of chitosan and ionic liquid were used in the preparation of a SnO nanoplate (SnO-IL, SnO-CS and SnO-IG). For the preparation of the ethyl pyridinium iodide, a mixture of pyridine and iodoethane (1: 2 molar ratio) was refluxed for 24 hours. The ionogel was formed using ethyl pyridinium iodide ionic liquid in chitosan that was dissolved in acetic acid (1 % v/v). By increasing NH3∙H2O, the pH of the ionogel reached 7-8. Then, the resultant IG was mixed with SnO in an ultrasonic bath for 1 h. The microstructure of the ionogel was involved as assembled unit via π-π, electrostatic and hydrogen bonding interactions to be three-dimensional networks. The intercalated ionic liquid and chitosan influenced the stability of the SnO nanoplates and improved band gap values. When chitosan was contained as the interlayer space of the SnO nanostructure, the resulting biocomposite formed a well-ordered flower-like SnO structure. These hybrid material structures were characterized by FT-IR, XRD, SEM, TGA, DSC, BET, and DRS techniques. The changes in the band gap values for photocatalysis applications were investigated. In the case of SnO, SnO-IL, SnO-CS, and SnO-IG, the band gap energy was 3.9, 3.6, 3.2, and 2.8 eV, respectively. The dye removal efficiency of SnO-IG was 98.5, 98.8, 97.9, and 98.4 % via the second-order kinetic model for Reactive Red 141, Reactive Red 195, Reactive Red 198, and Reactive Yellow 18, respectively. The maximum adsorption capacity of SnO-IG was 540.5, 584.7, 1501.5, and 1100.1 mg/g for Red 141, Red 195, Red 198, and Yellow 18 dyes, respectively. Also, an acceptable result (96.47 % dye removal) was obtained with the prepared SnO-IG biocomposite for dye removal from textile wastewater.


Assuntos
Quitosana , Líquidos Iônicos , Poluentes Químicos da Água , Quitosana/química , Líquidos Iônicos/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Iodetos , Fotólise , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química , Cinética
5.
Anal Methods ; 15(11): 1431-1440, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36852623

RESUMO

The present study deals with synthesis of N-(thiazol-2-ylcarbamothioyl) benzamide. It was utilized as a neutral ionophore for designing three types of chromium(III) sensors including coated wire ion selective electrodes (CW-ISEs), ion selective electrodes with liquid internal electrolyte (LIE-ISEs), and solid-state ion selective electrodes (SS-ISEs). UV-visible spectrophotometry was used to confirm the affinity of N-(thiazol-2-ylcarbamothioyl) benzamide to chromium(III). It was found that a membrane with a composition of 2% NaTPB, 8% ionophore, 60% DBP, and 30% PVC showed the best performance and a Nernstian slope of 21.6 mV per decade. Scanning electron microscopy was used to assess the PVC membrane morphology. The existence of chromium(III) in the liquid membrane matrix was proved by energy-dispersive X-ray spectroscopy. Detection limits for SS-ISE (1 × 10-6 M) and CW-ISE (1 × 10-6 M) were enhanced relative to LIE-ISE (1 × 10-5 M). All three electrodes showed a response time of about 5 s. The sensors' applicable pH range was 4.0-6.0. Fourier transform infrared spectra recorded through the electrode membrane showed that chromium(III) ion can interact with sulfur, nitrogen and oxygen atoms of N-(thiazol-2-ylcarbamothioyl) benzamide. The sensors were utilized as indicator electrodes in chromium(III) potentiometric titration with ethylenediaminetetraacetic acid and for directly measuring chromium(III) in some pharmaceutical samples.

6.
Sci Rep ; 12(1): 12431, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858985

RESUMO

A novel Zn (II) organic framework comprising 2-phenyl benzimidazole (ZPBIF-1) was synthesized by using a solvothermal method. The characterization of the synthesized MOF was performed utilizing XRD, SEM, FT-IR, 1H-NMR, 13C-NMR, MS, XPS, TG/DTA, and N2 sorption analysis. ZPBIF-1 was successfully utilized to remove Acid red 88, Basic Violet 14, Basic Blue 54, and Congo red dyes in aqueous solutions. In this study, some parameters, including adsorbent dosage, initial dye concentration, contact time, temperature, and pH, were examined. To evaluate the experimental data, Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich isotherm models were used. In this case, Langmuir is the most suitable model. Several kinetic models, including First-order, pseudo-first-order, second-order, and Pseudo-second-order kinetic models, Elovich's, and Weber's intraparticle diffusion models, were utilized to comprehend the detailed adsorption process. According to the pseudo-second-order kinetic model, dye sorption kinetics is best described. In addition, thermodynamic parameters like enthalpy (ΔH°), Gibbs free energy (ΔG°), and entropy (ΔS°) were also achieved and analyzed. The experimental studies thus suggest that Zn (II) metal-organic framework based on 2-phenyl benzimidazole could be a promising candidate for eliminating dyes from aqueous solution. Hence, the experimental studies suggest that a Zn (II) metal-organic framework based on 2-phenylbenzimidazole could be a promising candidate for eliminating dyes from aqueous solution. The maximum adsorption capacity of ZPBIF-1 was 1666.66, 1250, 1000, and 1250 mg/g for Acid red 88, Basic violet 14, Basic blue 54, and Congo red dyes, respectively. Furthermore, this method was used to remove contaminant dyes from textile wastewater, and an acceptable result was obtained.


Assuntos
Estruturas Metalorgânicas , Poluentes Químicos da Água , Purificação da Água , Adsorção , Benzimidazóis , Corantes/química , Vermelho Congo , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zinco/análise
7.
Environ Technol ; 43(14): 2113-2123, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33332242

RESUMO

Forward osmosis is an emerging membrane technology in water desalination. In this study, desalination of saline water via forward osmosis was investigated using a new magnetic osmotic agent. For this purpose, Fe3O4 nanoparticles covalently functionalised with tri-sodium citrate was synthesised and characterised. The structural examinations revealed that the sodium citrate had been immobilised onto the magnetic nanoparticles. The highest water flux was obtained 17.1 L M-2 h (LMH) per 80 g L-1 osmotic agent solution against deionised water, while the ratio of salt flux to water flux was very low (0.088 g L-1). The osmotic solution was evaluated for saline water desalination using different concentrations of sodium chloride (NaCl) as feed solutions. The average water fluxes of 6.2, 4.5, and 2.7 LMH was obtained for 0.1, 0.2, and 0.5 M salt solutions, respectively. The magnetic osmotic agent was separated by a magnet and re-used for several times without considerable decrease in the water flux.


Assuntos
Nanopartículas de Magnetita , Purificação da Água , Ácido Cítrico , Íons , Membranas Artificiais , Osmose , Águas Salinas , Cloreto de Sódio , Citrato de Sódio
8.
J Biomol Struct Dyn ; 40(15): 6910-6920, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33645454

RESUMO

To investigate the reduction of side effects of commercial antitumor drugs such as cisplatin, two new platinum and palladium complexes with a formula of [M(DACH)(tertamyl.dtc)]NO3 were synthesized (DACH is 1R, 2R-diaminocyclohexane, tertamyl-dtc is tertpentyl dithiocarbamate, and M is palladium or platin ionic metals) and characterized by spectroscopic methods. The in vitro cytotoxicity of these compounds against HT29 and Panc1 cell lines showed that the IC50 values against Panc1 cell line of [Pt(DACH)(tertamyl.dtc)]NO3 and [Pd(DACH)(tertamyl.dtc)]NO3 were 263.1 and 198.7 µM, and also against HT29 cell line were 241.9 and 258.2 µM, respectively. They were similar to the value obtained for oxaliplatin and lower than cisplatin value. Thermal stability and circular dichroism results demonstrated that both metal complexes could bind to DNA via electrostatic bonds. Due to electrostatic interaction, the configuration of B-DNA to C-DNA changed, though the possibility of groove interaction may be strengthened. Furthermore, molecular docking simulation showed higher negative docking energy for [Pd(DACH)(tertamyl.dtc)]NO3 complex with a higher tendency for DNA interaction. In vitro cytotoxicity of two new Pt and Pd compounds have been studied against two cell lines (HT29 and Panc 1), which are almost equal to the value obtained for oxaliplatin and they are lower than cisplatin value. Thermal stability studies and CD results demonstrated that both complexes bind to DNA via electrostatic bonds. Further, molecular docking showed higher negative docking energy for [Pd(DACH)(tertamyl.dtc)]NO3 complex with a higher tendency for interaction.Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Cisplatino , Antineoplásicos/química , Linhagem Celular , Cisplatino/química , Cicloexilaminas , DNA/química , Ligantes , Simulação de Acoplamento Molecular , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Oxaliplatina/farmacologia , Paládio/química , Paládio/farmacologia
9.
Comb Chem High Throughput Screen ; 24(8): 1261-1270, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33001007

RESUMO

AIMS AND OBJECTIVE: In this work, 1,3-oxazoles were generated using the multicomponent reaction of α-bromo ketones, alkyl (aryl) isothiocyanates, sodium hydride and Fe3O4 MNPs in the water at room temperature in good yields. The nanoparticles generated via the biosynthesis method have potential value in different purposes, such as organic synthesis. MATERIALS AND METHODS: To study the antioxidant ability of some synthesized thioxo-1,3-oxazoles, diphenyl-picrylhydrazine (DPPH) radical trapping and power of ferric reduction testes are employed. Among the studied thioxo-1,3-oxazoles, compound 4b have good power for radical trapping and reduction activity than the standard antioxidants such as BHT and TBHQ. In addition, the antimicrobial activity of some thioxo-1,3-oxazoles was studied, employing the disk diffusion test on Gram-positive bacteria and Gram-negative bacteria. The results of the disk diffusion test showed that compounds 4a, 4b, 4d and 4f prevented bacterial growth. RESULTS: Without employing catalyst, these reactions have low yield and busy mixture. The synthesis of compound 4a as sample reaction has a similar yield in the presence of ZnO-NPs and Fe3O4 MNPs (entry 20 and entry 30), but the removal of catalyst from the mixture of reaction after the completion of the reaction is comfortable in the presence of Fe3O4 MNPs. Structures of compound 4a-4i are confirmed by IR, 1H NMR and 13C NMR mass spectra. CONCLUSION: The reaction of α-bromo ketones, isothiocyanate and sodium hydride in the presence of the catalytic amount of Fe3O4 MNPs in water generates 1,3-oxazole derivatives in good yields. Some of the advantages of performing these reactions with the present procedure are to carry out these reactions in water as a green solvent and simple removal of catalyst.


Assuntos
Anti-Infecciosos , Nanopartículas de Magnetita , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/química , Catálise , Nanopartículas de Magnetita/química , Oxazóis
10.
Artigo em Inglês | MEDLINE | ID: mdl-32167425

RESUMO

The article has been withdrawn at the request of the authors and editor of the journal Combinatorial Chemistry & High Throughput Screening.Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused. BENTHAM SCIENCE DISCLAIMER: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

11.
J Biomol Struct Dyn ; 38(8): 2215-2228, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31204612

RESUMO

Cisplatin, carboplatin and oxaliplatin and their analogs are effective anticancer agents, but their clinical using is limited by some serious side effects. S,S donor ligands such as dithiocarbamates can be used to reduce some side effects. In this study, some novel water soluble complexes with formula of [Pt(bpy)(R.dtc)]NO3, where bpy is bipyridine and R.dtc is amyl-, isopentyl- or tertamyl-dtc (n-pentyl-, 3-metyl-butyl- and 2-methylbutan-dithiocarbamate, respectively) have been synthesized and characterized by elemental analysis, conductivity measurements and chemical analysis. The cytotoxic activities of synthesized complexes were investigated against human adenocarcinoma colorectal cell line (HT29) and human pancreatic cell line (Panc1), and compared with cisplatin and oxaliplatin, which display more anticancer activity for [Pt(bpy)(isopentyl.dtc)]NO3. The experimental fluorescence and circular dichroism results illustrated partially groove binding of [Pt(bpy)(amyl.dtc)]NO3 and [Pt(bpy)isopentyl.dtc)]NO3 on DNA, while [Pt(bpy)(tertamyl.dtc)]NO3 complex, can bind to DNA via intercalation. Finally, molecular docking simulation data of DNA interaction with three synthesized complexes showed [Pt(bpy)(amyl.dtc)]NO3 complex has the highest tendency and negative docking energy in structural change of DNA.Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Complexos de Coordenação , Antineoplásicos/farmacologia , Linhagem Celular , Cisplatino/farmacologia , Complexos de Coordenação/farmacologia , Humanos , Simulação de Acoplamento Molecular , Platina
12.
Artigo em Inglês | MEDLINE | ID: mdl-29366409

RESUMO

BACKGROUND: The development of multicomponent reactions (MCRs) in the presence of task-specific ionic liquids (ILs), used not only as environmentally benign reaction media, but also as catalysts, is a new approach that meet with the requirements of sustainable chemistry. In recent years, the use of ionic liquids as a green media for organic synthesis has become a chief study area. This is due to their unique properties such as non-volatility, non-flammability, chemical and thermal stability, immiscibility with both organic compounds and water and recyclability. Ionic liquids are used as environmentally friendly solvents instead of hazardous organic solvents. OBJECTIVE: We report the condensation reaction between α-oximinoketone and dialkyl acetylene dicarboxylate in the presence of triphenylphosphine to afford substituted pyrroles under ionic liquid conditions in good yields. RESULT: Densely functionalized pyrroles was easily prepared from reaction of α-oximinoketones, dialkyl acetylene dicarboxylate in the presence of triphenylphosphine in a quantitative yield under ionic liquid conditions at room temperature. CONCLUSION: In conclusion, ionic liquids are indicated as a useful and novel reaction medium for the selective synthesis of functionalized pyrroles. This reaction medium can replace the use of hazardous organic solvents. Easy work-up, synthesis of polyfunctional compounds, decreased reaction time, having easily available-recyclable ionic liquids, and good to high yields are advantages of present method.


Assuntos
Alcinos/química , Ácidos Graxos Insaturados/química , Líquidos Iônicos/química , Cetonas/química , Fosfinas/química , Pirróis/síntese química , Estrutura Molecular , Pirróis/química
13.
Artigo em Inglês | MEDLINE | ID: mdl-25128679

RESUMO

Copper oxide nanostructures have been synthesized by a simple reflux method in aqueous medium of pyridinium based ionic liquids. The structural and optical properties of CuO nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence spectroscopy (PL) and UV-visible. The morphologies of the nanostructures can be controlled by changing the amount of NaOH and ionic liquids. The results show that the use identical pyridinium based ionic liquids in ratio of 4:1 NaOH/Cu(OAc)2⋅H2O yield minor differences in morphology of CuO nanostructures. Different morphologies of CuO nanostructures were obtained by changing the ratio NaOH/Cu(OAc)2⋅H2O to 2:1. Ionic liquids play an important role on optical properties of CuO nanostructures. The results of optical measurements of the CuO nanostructures illustrate that band gaps are estimated to be 1.67-1.85 eV. PL patterns studies show that the ionic liquids can be effect on PL patterns of the samples. The reasons of these phenomena are discussed.


Assuntos
Cobre/química , Líquidos Iônicos/química , Nanoestruturas/química , Fenômenos Ópticos , Compostos de Piridínio/química , Cristalização , Luminescência , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Espectrofotometria Ultravioleta , Difração de Raios X
14.
Comb Chem High Throughput Screen ; 16(9): 726-30, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23713460

RESUMO

4-Benzothiazol-2-ylamino-4-oxo-2-butenoic acid, prepared from reaction of 2-aminobenzothiazole and maleic anhydride, are used as an acid component in Passerini three-component reaction, under solvent-free media, to produce unsaturated α-benzothiazole acyloxyamides in good yields.


Assuntos
Amidas/síntese química , Benzotiazóis/síntese química , Acilação , Amidas/química , Benzotiazóis/química , Anidridos Maleicos/química
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