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1.
J Sep Sci ; 47(3): e2300801, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356234

RESUMEN

Generic electromembrane extraction (EME) methods were developed and optimized for basic analytes of moderate or low polarity, employing prototype conductive vial EME equipment. Two generic methods, B1 and B2, were devised for mono- and dibasic compounds with distinct polarity windows: 2.0 < log P < 6.0 for B1 and 1.0 < log P < 4.5 for B2. In B1, 10 µL of 2-nitrophenyl octyl ether served as the liquid membrane, while B2 utilized 10 µL of 2-undecanone. Both methods involved the acidification of 125 µL of human plasma samples with 125 µL of sample diluent (0.5 M HCOOH for B1 and 1.0 M HCOOH for B2). The acceptor phase consisted of 250 µL of 100 mM HCOOH. Extraction was conducted for 30 min with agitation at 800 rpm, employing an extraction potential of 100 V for B1 and 50 V for B2. A set of 90 pharmaceutical compounds was employed as model analytes. Both B1 and B2 demonstrated high recoveries (40%-100%) for the majority of model analytes within their respective polarity windows. Intra-day precision was within 2.2% and 9.7% relative standard deviation. Both extraction systems exhibited stability in terms of current, matrix effect values were between 90% and 109%.

2.
J Sep Sci ; 47(1): e2300796, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38234030

RESUMEN

In this study, a hydroxyl-rich ferrofluid was prepared by dispersing silica-coated magnetic nanoparticles into a methyltrioctylammonium chloride-glycerol deep eutectic solvent and then employed in the preconcentration of trace-level of cinnamic acid derivatives (caffeic acid, p-hydroxycinnamic acid, ferulic acid, and cinnamic acid) in traditional Chinese medicine prior to high-performance liquid chromatography analysis. The structures of the synthesized materials were characterized by X-ray diffraction and infrared spectroscopy. The experimental parameters affecting the extraction performance, such as deep eutectic solvent composition, dosage of ferrofluid, pH of aqueous sample solution, salt concentration, extraction time, type, and volume of desorption solvent, were studied and optimized. Under the optimum conditions, the enrichment factors of four cinnamic acid derivatives were in the range of 107-114. Low detection limits (0.2-0.9 ng/mL), good precisions (relative standard deviations 1.2%-9.5%), and satisfactory recoveries (96.0%-104.7%) were achieved. Subsequently, the possible microextraction mechanism of the proposed method was explored and elucidated. It showed that the prepared ferrofluid is easily dispersed in the aqueous sample and achieved recovery after the extraction. The developed approach is a simple, convenient, and efficient method for preconcentration and determination of cinnamic acid derivatives in complex matrices.


Asunto(s)
Microextracción en Fase Líquida , Medicina Tradicional China , Microextracción en Fase Líquida/métodos , Disolventes Eutécticos Profundos , Cinamatos/análisis , Coloides/análisis , Solventes/química , Límite de Detección , Cromatografía Líquida de Alta Presión
3.
J Sep Sci ; 47(3): e2300745, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356226

RESUMEN

Understanding and comparing the applicability of electromembrane extraction (EME) and liquid-phase microextraction (LPME) is crucial for selecting an appropriate microextraction approach. In this work, EME and LPME based on supported liquid membranes were compared using biological samples, including whole blood, urine, saliva, and liver tissue. After optimization, efficient EME and LPME of clozapine from four biological samples were achieved. EME provided higher recovery and faster mass transfer for blood and liver tissue than LPME. These advantages were attributed to the electric field disrupting clozapine binding to interfering substances. For urine and saliva, EME demonstrated similar recoveries while achieving faster mass transfer rates. Finally, efficient EME and LPME were validated and evaluated combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The coefficient of determination of all methods was greater than 0.999, and all methods showed acceptable reproducibility (≤14%), accuracy (90%-110%), and matrix effect (85%-112%). For liver and blood with high viscosity and complex matrices, EME-LC-MS/MS provided better sensitivity than LPME-LC-MS/MS. The above results indicated that both EME and LPME could be used to isolate non-polar basic drugs from different biological samples, although EME demonstrated higher recovery rates for liver tissue and blood.


Asunto(s)
Clozapina , Microextracción en Fase Líquida , Cromatografía Liquida , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Microextracción en Fase Líquida/métodos , Membranas Artificiales
4.
J Sep Sci ; 47(1): e2300776, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38066356

RESUMEN

A microextraction based on pH-responsive deep eutectic solvent combined with high-performance liquid chromatography was developed for the separation, preconcentration, and determination of bisphenol A in water samples. Five deep eutectic solvents were prepared using thymol (hydrogen bond acceptor) and 6-, 8-, 9-, 10-, and 12-carbon carboxylic acids (hydrogen bond donor), and were used as extraction solvent. Herein, by alkalinizing the environment, phase transition takes place, and by adding acid, phase separation and extraction of analytes occur simultaneously. Some important parameters on the extraction such as deep eutectic solvent type, molar ratio of deep eutectic solvent components, deep eutectic solvent volume, potassium hydroxide concentration, hydrochloric acid volume, extraction time, and salt addition were optimized. Under the optimum conditions, intra- and interday precisions of the method based on seven replicate measurements of 10 µg L-1 of bisphenol A in water samples were 2.2% and 4.3%, respectively. The analytical performance of the method showed linearity over the concentration of 0.05-50 µg L-1 with the detection limit of 0.02 µg L-1 . The accuracy of the method was confirmed by spiking different concentrations of bisphenol A in real water samples and obtaining relative recoveries in the range of 92.5%-105.2%.

5.
J Sep Sci ; 47(17): e2400340, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39215580

RESUMEN

In this work, an easy, safe, simple, and efficient pH-switchable deep eutectic solvents (DESs)-based liquid phase microextraction followed by high-performance liquid chromatography-diode array detector analysis was developed for the determination of 1,3-dimethylamylamine (DMAA). The switchability of the obtained DESs was investigated by changing the pH. Then the best-selected DES was characterized and the application of the selected DES in the extraction of DMAA from sports nutrition and bodybuilding supplements was investigated. The DES synthesized from l-menthol: oleic acid in a molar ratio of 1:2 had the highest efficiency in the extraction of the target compound. Under the optimum conditions, (50 µL of DES, 100 µL of 4 mol/L KOH, 100 µL of 4 mol/L HCl, extraction time of 40 s and without salt addition) the calibration graph was linear in the range of 0.05-100 µg/kg and limit of detection was 0.02 µg/kg. The relative standard deviations including intra-day and inter-day for 10.0 µg/kg of DMAA in real samples were 2.7% (n = 7) and 5.3% (n = 7), respectively. The enrichment factor and percentage extraction recovery of the method were 283 and 85%, respectively. The relative recoveries for DMAA in different samples were in the range of 90%-109%.


Asunto(s)
Disolventes Eutécticos Profundos , Suplementos Dietéticos , Cromatografía Líquida de Alta Presión , Suplementos Dietéticos/análisis , Concentración de Iones de Hidrógeno , Disolventes Eutécticos Profundos/química , Aminas/análisis , Aminas/química , Microextracción en Fase Líquida
6.
J Sep Sci ; 47(9-10): e2400124, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38772717

RESUMEN

This study introduces a new in-syringe homogeneous liquid-phase microextraction method for the rapid on-site extraction of chloroanilines from water samples. Extraction was performed using a plastic syringe, eliminating the use of any electrical power source. Di-(2-ethylhexyl) phosphoric acid (DEHPA) served as the extractant. The process initially involved dissolving DEHPA in an alkaline solution to obtain a homogeneous solution. Subsequently, the sodium salt of DEHPA was precipitated by salting-out, and the resulting heterogeneous mixture was filtered using a syringe filter. The precipitate containing the analytes was then dissolved in methanol for analysis by high-performance liquid chromatography. Under optimal conditions, extraction recovery for chloroanilines ranged from 26% to 71%. Method linearity was evaluated within a concentration range of 1.0-100 µg/L, resulting in coefficients of determination exceeding 0.9987 for all analytes. Method detection limits ranged from 0.28 to 0.41 µg/L. Intra and inter-day precision values were below 9.5% and 10.8%, respectively. The developed method was applied to determine chloroanilines in real waters, yielding acceptable recoveries ranging from 80% to 109% for spiked tap, rain, and stream waters. Additionally, the method was successfully employed for on-site extraction of target contaminants, demonstrating no statistically significant differences compared to laboratory results.

7.
Environ Monit Assess ; 196(5): 454, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622372

RESUMEN

This work presents a sensitive and accurate analytical method for the determination of phenytoin at trace levels in domestic wastewater and synthetic urine samples by gas chromatography-mass spectrometry (GC-MS) after the metal sieve-linked double syringe liquid-phase microextraction (MSLDS-LPME) method. A metal sieve was produced in our laboratory in order to disperse water-immiscible extraction solvents into aqueous media. Univariate optimization studies for the selection of proper extraction solvent, extraction solvent volume, mixing cycle, and initial sample volume were carried out. Under the optimum MSLDS-LPME conditions, mass-based dynamic range, limit of quantitation (LOQ), limit of detection (LOD), and percent relative standard deviation (%RSD) for the lowest concentration in calibration plot were figured out to be 100.5-10964.2 µg kg-1, 150.6 µg kg-1, 45.2 µg kg-1, and 9.4%, respectively. Detection power was improved as 187.7-folds by the developed MSLDS-LPME-GC-MS system while enhancement in calibration sensitivity was recorded as 188.0-folds. In the final step of this study, the accuracy and applicability of the proposed system were tested by matrix matching calibration strategy. Percent recovery results for domestic wastewater and synthetic urine samples were calculated as 95.6-110.3% and 91.7-106.6%, respectively. These results proved the accuracy and applicability of the proposed preconcentration method, and the obtained analytical results showed the efficiency of the lab-made metal sieve apparatus.


Asunto(s)
Microextracción en Fase Líquida , Contaminantes Químicos del Agua , Cromatografía de Gases y Espectrometría de Masas/métodos , Aguas Residuales , Fenitoína/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Solventes/química , Agua/análisis , Microextracción en Fase Líquida/métodos , Límite de Detección
8.
Ann Pharm Fr ; 82(3): 483-492, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37923008

RESUMEN

This study demonstrates an effective, simple, and selective method for monitoring mesalazine in pharmaceutical formulations using liquid phase micro-extraction (LPME) and spectrophotometry. Combining LPME with spectrophotometry is an efficient method for analysing various compounds in different matrices. This method is based on extracting the ion-pair formed between the blue indophenol produced by the oxidative reaction of mesalazine and syringic acid in an alkaline medium and a quaternary ammonium salt into a micro-volume of organic solvent. The experimental parameters influencing LPME performance, such as the type and concentration of the quaternary ammonium ion salt and the type and volume of the extractant solvent, were optimised for optimal detection. The linear range and the limit of detection for measuring red species in pharmaceutical formulations were determined to be 0.005-0.080 µg/mL-1 and 0.003 µg/mL-1, respectively, with a relative standard deviation of 4-6%. The method had a preconcentration factor of 50 at 520nm, making it highly efficient and reliable for monitoring mesalazine in pharmaceutical formulations.

9.
Anal Bioanal Chem ; 415(9): 1765-1776, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36820909

RESUMEN

Aromatic amines (AA) are carcinogenic compounds that can enter the human body through many sources, one of the most important being tobacco smoke. They are excreted with the urine, from which they can be extracted and measured. To that end, hollow fiber-liquid-phase microextraction (HF-LPME) and parallel artificial liquid membrane extraction (PALME) were optimized for the analysis of representative aromatic amines, as alternatives to liquid-liquid extraction (LLE). Relevant extraction parameters, namely organic solvent, extraction time, agitation speed, and acceptor solution pH, were studied, and the two optimized techniques-HF-LPME: dihexyl ether, 45 min, 250 rpm, and pH 1; PALME: undecane, 20 min, 250 rpm and pH 1-were compared. Comparison of the optimized methods showed that significantly higher recoveries could be obtained with PALME than with HF-LPME. Therefore, PALME was further validated. The results were successful for nine different AA, with regression coefficients (R2) of at least 0.991, limits of detection (LOD) of 45-75 ng/L, and repeatability and peak area relative standard deviations (RSD) below 20%. Furthermore, two urine samples from smokers were measured as proof of concept, and 2-methylaniline was successfully quantified in one of them. These results show that PALME is a great green alternative to LLE. Not only does it use much smaller volumes of toxic organic solvents, and sample-enabling the study of samples with limited available volumes-but it is also less time consuming and labor intensive, and it can be automated.


Asunto(s)
Microextracción en Fase Líquida , Membranas Artificiales , Humanos , Solventes/química , Microextracción en Fase Líquida/métodos , Aminas , Extracción Líquido-Líquido
10.
J Sep Sci ; 46(19): e2300326, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37485627

RESUMEN

A simple and rapid instantaneous nebulization dispersive liquid-phase microextraction method was developed, and combined with high-performance liquid chromatography for determination of the contents of seven analytes in traditional Chinese medicines. In this study, using the sprinkler device to achieve instantaneous synchronous dispersion and extraction, only one spray can rapidly achieve the concentration and enrichment of seven kinds of chalcone and isoflavones. The key factors affecting the extraction efficiency were optimized including the type and volume of extractant, the pH and salt concentration of the sample phase, and the number of dispersion. Under the optimal conditions, the enrichment factor of the target analytes ranged from 103.1 to 180.9, with good linearity and correlation coefficients above 0.9970. The limits of detection ranged from 0.02 to 0.15 ng/mL, with good accuracy (recoveries 91.1 to 108.9%) and precision (relative standard deviations 1.5-7.1%). This method has short extraction time (2 s), low organic solvent consumption and high enrichment effect, so it has a wide application prospects.


Asunto(s)
Chalcona , Chalconas , Isoflavonas , Microextracción en Fase Líquida , Cromatografía Líquida de Alta Presión , Medicina Tradicional China , Microextracción en Fase Líquida/métodos
11.
J Sep Sci ; 46(16): e2300068, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37407502

RESUMEN

In this study, for the first time, a deep eutectic solvent-based microwave-assisted extraction was combined with ionic liquid-based temperature controlled liquid phase microextraction for the extraction of several aflatoxins from cheese samples. Briefly, the analytes are extracted from cheese sample (3 g) into a mixture of 1.5 mL choline chloride:ethylene glycol deep eutectic solvent and 3.5 mL deionized water by exposing to microwave irradiations for 60 s at 180 W. The liquid phase was taken and mixed with 55 µL 1-hexyl-3-methylimidazolium hexafluorophosphate. By cooling the solution in the refrigerator centrifuge, a turbid state was obtained and the analytes were extracted into the ionic liquid droplets. The analytes were determined by high-performance liquid chromatography equipped with fluorescence detector. Low limits of detection (9-23 ng kg-1 ) and quantification (30-77 ng kg-1 ), high extraction recovery (66%-83%), acceptable enrichment factor (40-50), and good precision (relative standard deviations ≤ 5.2%) were obtained using the offered approach. These results reveal the high extraction capability of the method for determination of aflatoxins in the cheese samples. In this method, there was no need for organic solvents and it can be considered as green extraction method.


Asunto(s)
Queso , Líquidos Iónicos , Microextracción en Fase Líquida , Microextracción en Fase Líquida/métodos , Disolventes Eutécticos Profundos , Microondas , Temperatura , Solventes/química , Límite de Detección
12.
Biomed Chromatogr ; 37(6): e5624, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36920060

RESUMEN

This study used a liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection as an eco-efficient, convenient-to-use, cost-effective, sensitive, rapid, and efficient method for extracting, preconcentrating, and quantifying trace amounts of diazinon in river water samples. As a switchable solvent, triethylamine (TEA) was used. In situ generation of CO2 using effervescent tablet containing Na2 CO3 and citric acid changed the hydrophobic TEA to the hydrophilic protonated triethylamine carbonate (P-TEA-C). CO2 removal from the specimen solution using NaOH caused P-TEA-C to be converted into TEA and led to phase separation, during which diazinon was extracted into the TEA phase. The salting-out process was helpful in enhancing extraction efficiency. In addition, a number of significant parameters that affect extraction recovery were examined. Under optimum conditions, the limit of detection and limit of quantitation were 0.06 and 0.2 ng/ml, respectively. The extraction recovery percentage and pre-concentration factor were obtained at 95 and 190%, respectively, and the precision (inter- and intra-day, relative standard deviation %, n = 5) was <5%.


Asunto(s)
Diazinón , Microextracción en Fase Líquida , Ionización de Llama/métodos , Solventes/química , Diazinón/análisis , Dióxido de Carbono , Cromatografía de Gases/métodos , Microextracción en Fase Líquida/métodos , Agua/química , Límite de Detección
13.
Mikrochim Acta ; 190(5): 170, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-37016169

RESUMEN

A new microfluidic device to enhance the enrichment factor in miniaturized systems is proposed. The microfluidic system was design for liquid phase microextractions, and it was applied to the simultaneous extraction of acidic compounds of a wide range of polarity (0.5 < log P < 3). The device operated under stagnant acceptor phase conditions and all the operational parameters involved were optimized. Tributyl phosphate was found to be a new highly efficient supported liquid membrane to simultaneously extract analytes of very different polarities. The optimal donor and acceptor phase were pH 2 and pH 13, respectively. The donor flow rate and the extraction time were investigated simultaneously, offering great versatility with high enrichment factors (EFs). Limits of quantitation were within 0.02 and 0.09 µg mL-1 for all compounds at 10 µL min-1 as donor flow rate and 20-min extractions, offering EFs between 11 and 18 with only 200-µL sample volume consumption. The method was successfully applied to human urine samples, observing recoveries between 47 and 90% for all compounds. This new proposed microfluidic system increases the wide range of applications, especially when the analytes are present in lower concentrations in the sample.


Asunto(s)
Dispositivos Laboratorio en un Chip , Microextracción en Fase Líquida , Humanos , Microfluídica
14.
Environ Monit Assess ; 195(9): 1063, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37594584

RESUMEN

This study presents a highly sensitive and accurate analytical strategy for the determination of fenuron in wastewater samples using gas chromatography-mass spectrometry (GC-MS). Simultaneous derivatization and spray-based fine droplet formation-liquid phase microextraction (SFDF-LPME) method was developed and performed to achieve low detection limits. The parameters of the derivatization and SFDF-LPME method were optimized by univariate approach to improve sensitivity and selectivity. Under the optimum SFDF-LPME-GC-MS conditions, the limit of detection (LOD) and limit of quantitation (LOQ) were found to be 0.15 and 0.49 mg/kg, respectively. In addition, the linear range was calculated as 0.51-24.50 mg/kg. Recovery studies were carried out on wastewater samples to determine the accuracy of the developed method and its applicability to real sample matrix. Matrix matching calibration strategy was applied to eliminate/reduce any possible interference effects caused by the complexity of the wastewater matrix and to increase the accuracy of the analytical results. Percent recovery results varied between 85.9 and 120.9% with small percent relative standard deviation values. These results were satisfactory in terms of the accuracy and applicability of the proposed method for wastewater samples.


Asunto(s)
Monitoreo del Ambiente , Aguas Residuales , Calibración , Cromatografía de Gases y Espectrometría de Masas
15.
Environ Monit Assess ; 196(1): 77, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38135867

RESUMEN

This study employed simple polystyrene-coated magnetite nanoparticles (PS@MNPs)-assisted batch adsorption process for the removal of two antidepressant active ingredients (amitriptyline HCl and sertraline HCl) from hospital wastewater. Dominant parameters of the adsorption process including pH, adsorbent amount, and contact period were optimized through the univariate approach to enhance the adsorption efficiency. Upon reaching optimum adsorption conditions, equilibrium experiments were performed by spiking the adsorbates in hospital wastewater in the concentration range of 100-2000 µg/L. The concentrations of the adsorbates in the effluent were calculated using the matrix-matching calibration strategy to enhance the accuracy of quantification. A validated switchable solvent-based liquid phase microextraction (SS-LPME) method was employed to enrich the two active pharmaceutical ingredients (APIs) prior to sensitive determination with GC-MS (gas chromatography-mass spectrometry). The equilibrium data were mathematically modeled employing the Langmuir and Freundlich adsorption isotherm models. The isotherm constants were calculated, and the results showed that both the isotherm models fitted well with the experimental data. The efficient and simple batch adsorption strategy reported in this study was successfully employed to remove amitriptyline HCl and sertraline HCl from hospital wastewater at low concentrations.


Asunto(s)
Nanopartículas de Magnetita , Contaminantes Químicos del Agua , Amitriptilina/análisis , Aguas Residuales , Medicamentos a Granel , Poliestirenos/análisis , Sertralina/análisis , Adsorción , Nanopartículas de Magnetita/química , Monitoreo del Ambiente , Antidepresivos/análisis , Contaminantes Químicos del Agua/análisis , Cinética , Concentración de Iones de Hidrógeno
16.
Electrophoresis ; 43(15): 1567-1576, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35567359

RESUMEN

Dynamic single-drop microextraction (SDME) was automatized employing an Arduino-based lab-made Cartesian robot and implemented to determine parabens in wastewater samples in combination with liquid chromatography-tandem mass spectrometry. A dedicated Arduino sketch controls the auto-performance of all the stages of the SDME process, including syringe filling, drop exposition, solvent recycling, and extract collection. Univariate and multivariate experiments investigated the main variables affecting the SDME performance, including robot-dependent and additional operational parameters. Under selected conditions, limit of detections were established at 0.3 µg/L for all the analytes, and the method provided linear responses in the range between 0.6 and 10 µg/L, with adequate reproducibility, measured as intraday relative standard deviations (RSDs) between 5.54% and 17.94%, (n = 6), and inter-days RSDs between 8.97% and 16.49% (n = 9). The robot-assisted technique eased the control of dynamic SDME, making the process more feasible, robust, and reliable so that the developed setup demonstrated to be a competitive strategy for the automated extraction of organic pollutants from water samples.


Asunto(s)
Microextracción en Fase Líquida , Robótica , Contaminantes Químicos del Agua , Cromatografía Liquida , Microextracción en Fase Líquida/métodos , Parabenos/análisis , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
17.
Biomed Chromatogr ; 36(11): e5461, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35862241

RESUMEN

In this study, a deep eutectic solvent as the acceptor phase was applied in three-phase hollow fiber liquid-phase microextraction for the microextraction of two pyrethroids (permethrin as well as deltamethrin) from environmental water samples prior to HPLC-UV. A deep eutectic solvent was synthesized of tetrabutylammonium bromide-decanoic acid (in a ratio of 1:2) as an acceptor phase and 1-decanol was applied as a supported liquid membrane. Some main variables affecting the extraction recoveries, comprising the types/contents of extraction solvent and acceptor phase, stirring speed, sample phase pH and extraction time, were checked and optimized. Under optimal conditions, the detection limits and limits of quantitation determined were 0.09-0.12 and 0.29-0.39 µgl-1 for deltamethrin and permethrin, respectively. The enrichment factors were 627 and 613, while the relative standard deviations (n = 5) were 4.8 and 5.7%, for deltamethrin and permethrin, respectively. The created technique was assessed as satisfactory to ascertain the two pyrethroid poisons (permethrin and deltamethrin) in environmental water samples.


Asunto(s)
Insecticidas , Microextracción en Fase Líquida , Venenos , Piretrinas , Cromatografía Líquida de Alta Presión/métodos , Disolventes Eutécticos Profundos , Microextracción en Fase Líquida/métodos , Nitrilos , Permetrina , Solventes/química , Agua/química
18.
Anal Bioanal Chem ; 413(2): 577-584, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33205254

RESUMEN

For simultaneous analysis of four fat-soluble tocopherols (α-, ß-, γ-, and δ-) in edible oils, an efficient and green method using deep eutectic solvent-based liquid-phase microextraction (DES-LPME) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The DESs formed by different quaternary ammonium salts and ethanol were used as the extractants. Tetrabutylammonium chloride (TBAC)-ethanol DES at a molar ratio of 1:2 achieved the best extraction efficiency. Under the optimized conditions, the detection limits were in the range of 2.1-3.0 ng mL-1. The intra-day and inter-day repeatability were in the ranges of 3.9-5.3% and 4.8-7.1%, respectively, and the recoveries for the real samples varied from 80.7% to 105.4%. The developed method was successfully employed for the determination of all four tocopherol homologues with an RP-HPLC system containing a COSMOSIL π-NAP column in five edible oils collected locally. Graphical abstract.


Asunto(s)
Microextracción en Fase Líquida/métodos , Aceites de Plantas/análisis , Solventes/química , Tocoferoles/análisis , alfa-Tocoferol/análisis , beta-Tocoferol/análisis , gamma-Tocoferol/análisis , Técnicas de Química Analítica , Cromatografía Líquida de Alta Presión , Límite de Detección , Compuestos de Amonio Cuaternario/análisis , Reproducibilidad de los Resultados
19.
Anal Bioanal Chem ; 413(14): 3717-3723, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33884461

RESUMEN

In this work, hippuric acid (log P = 0.5), anthranilic acid (log P = 1.3), ketoprofen (log P = 3.6), and naproxen (log P = 3.0) were simultaneously extracted by a green microfluidic device based on the principles of liquid-phase microextraction (LPME). Different deep eutectic solvents (DESs) were investigated as supported liquid membrane (SLM), and a mixture of camphor and menthol as eutectic solvents in the molar ratio 1:1 was found to be highly efficient for the simultaneous extraction of non-polar and polar acidic drugs. LPME was conducted for 6 min per sample. Urine sample was delivered to the system at 1 µL min-1, and target analytes were extracted exhaustively (75-100% recovery) across the DES SLM, and into pure aqueous phosphate buffer pH 11.0 delivered as acceptor at 1 µL min-1. The acceptor was analyzed with liquid chromatography-UV detection. Interestingly, the DES enabled extraction of both the polar and non-polar model analytes at the same time; all chemicals were green and non-hazardous, and the chemical waste was less than 1 mg per sample.


Asunto(s)
Ácidos/aislamiento & purificación , Ácidos/orina , Microextracción en Fase Líquida/instrumentación , Adulto , Diseño de Equipo , Femenino , Humanos , Dispositivos Laboratorio en un Chip , Solventes
20.
Anal Bioanal Chem ; 413(9): 2467-2479, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33532915

RESUMEN

The hollow fiber liquid-phase microextraction allows highly selective concentration of organic compounds that are at trace levels. The determination of those analytes through the supercritical fluid chromatography usage is associated with many analytical benefits, which are significantly increased when it is coupled to a mass spectrometry detector, thus providing an extremely sensitive analytical technique with minimal consumption of organic solvents. On account of this, a hollow fiber liquid-phase microextraction technique in two-phase mode combined with supercritical fluid chromatography coupled to mass spectrometry was developed for quantifying 19 multiclass emerging contaminants in water samples in a total chromatographic time of 5.5 min. The analytical method used 40 µL of 1-octanol placed in the porous-walled polypropylene fiber as the acceptor phase, and 1 L of water sample was the donor phase. After extraction and quantification techniques were optimized in detail, a good determination coefficient (r2 > 0.9905) in the range of 0.1 to 100 µg L-1, for most of the analytes, and an enrichment factor in the range of 7 to 28,985 were obtained. The recovery percentage (%R) and intraday precision (%RSD) were in the range of 80.80-123.40%, and from 0.48 to 16.89%, respectively. Limit of detection and quantification ranged from 1.90 to 35.66 ng L-1, and from 3.41 to 62.11 ng L-1, respectively. Finally, the developed method was successfully used for the determination of the 19 multiclass emerging contaminants in superficial and wastewater samples.

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