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1.
Turk J Chem ; 48(4): 620-630, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39296787

RESUMO

A novel Fe3O4@coPPy-PTH nanocomposite-based sorbent was prepared via in situ oxidative polymerization using Fe3O4 nanoparticles with spherical and flower-like morphologies of thiophene and pyrrole as the feedstocks. The synthesized nanocomposite displayed sensitive extraction and determination of metal ions Co(II), Cr(III), and Ni(II) without a chelating agent, followed by microsample injection system-flame atomic absorption spectrometry. Advanced spectroscopic and imaging techniques including scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy were used to characterize the composition and morphology of the Fe3O4@coPPy-PTH nanocomposite. SEM observations showed that the size of the Fe3O4 nanoparticles changed from 30 nm to 120 nm in diameter after copolymer (PPy-PTH) coating. The Fe3O4@coPPy-PTH nanocomposite has good dispersion properties and stability in strong acid solutions. For effective extraction of the studied analytes, the influence of sample pH, volume of sample solution and eluent, amount of adsorbent, and interference of coexisting metal ions were optimized. Under the optimum conditions, preconcentration factors were obtained as 25 for all analytes. The calibration curves were linear in the range of 0.0-10.0 µg L-1 with coefficients of determination (R2) greater than 0.9957 for all three analytes. Limits of detection (S/N = 3) were calculated in the range of 0.17-0.23 µg L-1. Precision values, expressed as relative standard deviations, were lower than 3.0%, and relative recoveries were obtained in the range of 88.6%-103.6%. The proposed method (Fe3O4@coPPy-PTH/MSPE/MIS-FAAS) was successfully applied to extract and determine the studied metal ions in beer, wine, and nonalcoholic beverage samples.

2.
ACS Omega ; 9(25): 27446-27457, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947832

RESUMO

In the current study, we report the synthesis of a novel composite material composed of banana peel activated carbon (BPAC), nickel iron oxide (NiFe2O4), and manganese cobalt iron layered double hydroxide (MnCoFe-LDH) to create a high-performance electrochemical sensor to detect Palbociclib (PLB). The composite was successfully immobilized on a glassy carbon electrode (GCE) surface to create a modified electrode. The performance of the electrode was thoroughly evaluated, considering parameters such as electroactive surface areas (ESA), electron transfer rate constant (k0), and exchange current density (j0). The developed BPAC/NiFe2O4/MnCoFe-LDH/GCE exhibited a wide linear dynamic range of 0.01-13.0 µM for PLB concentration, accompanied by a detection limit at a low level (3.5 nM). Furthermore, it can be applied to the determination of PLB in human urine and pharmaceutical samples with excellent recoveries (98.5-102.9%) and RSD values lower than 3%, establishing its potential for precise PLB determination in pharmaceutical and biological samples. This research contributes to the advancement of electrochemical sensor technology for the detection of important anticancer drugs in real-world applications.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 319: 124552, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38820813

RESUMO

In the current study, a wide range of deep eutectic solvents (DESs) with different properties (hydrophilic, hydrophobic, ionic, and nonionic) were prepared in the initial phase. Subsequently, an assessment was conducted to evaluate some characteristics of the produced DESs, including their stability at room temperature and their capacity to extract three distinct types of analytes (anionic, cationic, and non-ionic) simultaneously through hollow fiber-liquid phase microextraction (HF-LPME) technique. To carry out the extraction procedure, the prepared DESs were inserted into the pores (as supported liquid membrane (SLM)) and lumen of hollow fiber membrane (HF) to apply two-phase and three-phase HF-LPME techniques. After a thorough evaluation, the three-phase HF-LPME technique (HF(3)-LPME) was chosen by using a mixture of menthol/TBAB-based hydrophobic DES (DES-35) as SLM and the mixture of malic acid/citric acid/water-based hydrophilic DES (DES-2) as an extraction solvent in the lumen of HF. All factors affecting the extraction recovery (including pH, extraction time, extraction temperature, stirring speed, and salt effect) were optimized utilizing the one-variable-at-a-time (OVAT) methodology. After applying the extraction procedure, all extracted samples were analyzed using the UV-Vis spectrometer and results were recorded at different wavelengths including 655 nm for Methylene blue, 550 nm for Amaranth, and 375 nm for Quercetin. The calibration graphs showed linearity in the range of 20.0-1500 µg/L, with a limit of detection of 6.2-15.1 µg/L and correlation coefficients higher than 0.9913 for the studied analytes. Moreover, the intra-day RSD, inter-day RSD, preconcentration factor (PF), enrichment factors (EF), and extraction recoveries (ER%) were obtained in the range of 3.1-4.8, 3.8-6.7, 125, 102.9-111.4, and 82.3-89.1 %, respectively. The use of the selected DES in the HF-LPME methodology resulted in an ecologically friendly strategy, as evidenced by the use of green metrics from the SPMS tool. The proposed strategy is also considered environmentally friendly due to its use of minimal solvents, waste reduction, and low energy consumption. The proposed technique effectively and simultaneously extractedmethylene blue, amaranth, and quercetin analytes in different real samples.

4.
Talanta ; 269: 125401, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979509

RESUMO

For the first time, a fast and easy extraction method based on a unique reusable and switchable deep eutectic solvent (made of octylamine, succinic acid, and water as precursors) was presented and utilized for the microextraction and determination of curcumin as a model analyte. The main factors used to induce a phase transition in the as-prepared deep eutectic solvent were solutions of NaOH and HCl. Among the standout characteristics of the suggested deep eutectic solvent are the removal of toxic organic solvents like THF, the lack of a need for centrifugation, and the ability to be reused in subsequent extractions. The influence of effective parameters (i.e., proportions of deep eutectic solvent structure components, volume of prepared deep eutectic solvent, volume and concertation of NaOH, volume of HCl, and salt effect) on the extraction procedure were investigated. The calibration curve also was linear in the range of 35-500 µg L-1 with coefficients of determination (R2) of 0.9976. Limit of detection (S/N = 3) 10.0 µg L-1, the limit of quantification (LOQ) of 35.0 µg L-1, the relative standard deviations (RSDs %) composed of intra-day RSD (4.7) and inter-day RSD (6.4), preconcentration factor of 40.0, enrichment factor of 38.68, and relative recovery of 92.6%-100.3 % were achieved. The reusable and switchable deep eutectic solvent based-dispersive liquid-liquid microextraction technique was proficiently employed to expedite easy and fast extraction of curcumin from water and food samples.


Assuntos
Curcumina , Microextração em Fase Líquida , Solventes/química , Água/química , Curcumina/análise , Solventes Eutéticos Profundos , Hidróxido de Sódio , Limite de Detecção , Microextração em Fase Líquida/métodos
5.
J Chromatogr A ; 1609: 460497, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31500883

RESUMO

This study introduces micrometric carbon strands as a suitable fiber for headspace solid phase microextraction. Compared to previous supports, carbon fibers have mechanical flexibility, wide thermal expansion, and a large surface area, which is an important factor in headspace solid phase microextraction. The electrophoretic technique was applied to modify the surface of stainless steel and carbon fibers with polypyrrole. Modified carbon fibers were used for extraction of 2-pentylfuran (2-PF) as a model analyte from patients' breath and coffee samples. 2-PF belongs to the furan family, which was suggested as a biomarker for Aspergillus fumigatus and was classified as a possible carcinogen. 2-PF can be found in many heat-processed foods and drinks. The separation and detection of the analyte was performed by gas chromatography coupled to mass spectrometry. The effective factors in the extraction performance of the analyte by carbon fiber supports were investigated and optimized. Under optimized extraction conditions (temperature, 20 °C; time, 15 min; desorption temperature, 200 °C; desorption time, 2 min; salt concentration, 10% w/v; and stirring rate, 700 rpm), the limit of detection was calculated as 0.05 ng mL-1, whereas repeatability and fiber-to-fiber reproducibility (RSD %) was found to be in the range of 3.2-4.1%. The experimental results showed that the proposed fiber had greater extraction performance for 2-pentylfuran.


Assuntos
Testes Respiratórios/métodos , Fibra de Carbono/química , Furanos/análise , Polímeros/química , Pirróis/química , Microextração em Fase Sólida/métodos , Adolescente , Adsorção , Adulto , Biomarcadores/análise , Feminino , Humanos , Limite de Detecção , Masculino , Nitrogênio/química , Reprodutibilidade dos Testes , Temperatura , Adulto Jovem
6.
J Sep Sci ; 42(8): 1620-1628, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30758140

RESUMO

In the present study, a supramolecular solvent was formed from reverse micelle aggregates of octanol. The proposed supramolecular solvent was used for rapid extraction of some antidepressants drugs including amitriptyline, imipramine, desipramine, maprotiline, sertraline, and doxepin from biological samples. Alkanol-based supramolecular solvents have a unique array of physicochemical properties, making them a very attractive alternative to replace organic solvents in analytical extractions. The parameters affecting the extraction of target analytes (i.e., the volume of tetrahydrofuran and octanol as the major components comprising the supramolecular solvent, chain length of alkanols, sample solution pH, salt addition, and ultrasonic time) were investigated and optimized by factor by factor optimization method. Under the optimum conditions, preconcentration factors of 470, 490, 460, 385, 370, and 430 were obtained for amitriptyline, doxepin, imipramine, desipramine, maprotiline, and sertraline, respectively. The linear ranges and coefficients of determination (R2 ) were obtained in the range of 0.01-100 µg/L and 0.9974-0.9991, respectively. Also the limits of detection (S/N = 3) of 0.003-0.03 µg/L, and precisions (n = 5) of 4.9-8.9% were calculated. Finally, the method was successfully applied for the extraction of antidepressant drugs in biological samples, and relative recoveries in the range of 91-102% were obtained.


Assuntos
Antidepressivos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Ultrassom/métodos , Antidepressivos/sangue , Antidepressivos/urina , Furanos/química , Humanos , Limite de Detecção , Octanóis/química , Solventes/química
7.
J Sep Sci ; 40(24): 4788-4795, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29067793

RESUMO

Liquid-phase microextraction based on gemini-based supramolecular solvent was successfully applied as a preconcentration step before gas chromatography with mass spectrometry. To eliminate the interferences of gemini surfactant, the analytes were back-extracted into an immiscible organic solvent in the presence of ultrasonic sound waves. Three phthalate esters (di-n-butyl-, butylbenzyl-, bis(2-ethylhexyl)-, and di-n-octyl phthalatic esters) were used as target analytes. The effective parameters on extraction efficiency of the target analytes (i.e., the amount of surfactant and volume of propanol as major components making up the supramolecular solvent, ionic strength, hexane volume, and ultrasound time) were investigated and optimized by a one-variable-at-a-time method. Under the optimum conditions, the preconcentration factors of the analytes were in the range of 95-182. The linear dynamic range of 0.05-200.00 µg/L with a correlation of determination of (R2 ) ≥ 0.9935 was obtained. The proposed method had an excellent limit of detection (S/N = 3) of 0.01 for di-n-octyl and 0.02 µg/L for butylbenzyl- and di-n-butyl-phthalatic ester. Good relative recoveries in the range of 85.7-105.2% guaranteed the accuracy of the amount of phthalates distinguished in the nonspiked samples.

8.
Anal Chim Acta ; 953: 1-9, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28010737

RESUMO

A new supramolecular solvent (SUPRAS) made up of aggregates of gemini surfactant was introduced. A microextraction method, based on the SUPRAS followed with high performance liquid chromatography-ultraviolet detection, was applied for the determination of parabens in cosmetics, beverages and water samples. A SUPRAS is a nano-structured liquid made up of surfactant aggregates synthesized through a self-assembly process. In the present work, a new gemini-based SUPRAS was introduced. Methyl paraben (MP), ethyl paraben (EP), and propyl paraben (PP) were extracted on the basis of π-cation and Van der Waals interactions into the SUPRAS. The parameter affecting the extraction of target analytes (i.e., the amount of surfactant and volume of propanol as major components comprising the supramolecular solvent, sample solution pH, salt addition, ultrasonic and centrifugation time) were investigated and optimized by one-variable-at-a-time method. Under the optimum conditions, the preconcentration factors of 98, 143 and 156 were obtained for MP, EP and PP, respectively. The linearity ranged from 0.5 to 0.7-200 µg L-1 with the correlation of determination of (R2) ≥ 0.9938. The gemini-based SUPRAS followed by HPLC-UV has been found to have excellent detection sensitivity with a limit of detection (LOD, S/N = 3) of 0.5 µg L-1 for EP and PP, and 0.7 µg L-1 for MP. Good recoveries over the range of 92.0-108.3% assured the accuracy of the amount of parabens distinguished in the non-spiked samples.


Assuntos
Microextração em Fase Líquida , Propanóis/química , Solventes/química , Tensoativos/química , Bebidas/análise , Cromatografia Líquida de Alta Pressão , Cosméticos/análise , Água Potável/análise , Águas Residuárias/análise
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