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1.
J Sep Sci ; 43(13): 2626-2635, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32259348

RESUMO

A simple, fast, and sensitive analytical protocol using fabric-phase sorptive extraction followed by high performance liquid chromatography with ultraviolet detection has been developed and validated for the extraction of five parabens including methylparaben, ethylparaben, propylparaben, butylparaben, and benzylparaben. In the present work, sol-gel polyethylene glycol coated fabric-phase sorptive extraction membrane is used for the preconcentration of parabens (polar) from complex matrices. The use of fabric-phase sorptive extraction membrane provides a high surface area which offers high sorbent loading, shortened equilibrium time, and overall decrease in the sample preparation time. Various factors affecting the performance of fabric-phase sorptive extraction, including extraction time, eluting solvent, elution time, and pH of the sample matrix, were optimized. Separation was performed using a mobile phase consisting of water:acetonitrile (63:37; v/v) at an isocratic elution mode at a flow rate of 0.9 mL/min with wavelength at 254 nm. The calibration curves of the target analytes were prepared with good correlation coefficient values (r2  > 0.9955). The limit of detection values range from 0.252 to 0.580 ng/mL. Finally, the method was successfully applied to various cosmetics and personal care product samples such as rose water, deodorant, hair serum, and cream with extraction recoveries ranged between 88 and 122% with relative standard deviation <5%.


Assuntos
Cosméticos/química , Parabenos/análise , Adsorção , Cromatografia Líquida de Alta Pressão , Espectrofotometria Ultravioleta
2.
J Sep Sci ; 42(14): 2407-2417, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31074186

RESUMO

A rapid extraction and cleanup method using selective fabric phase sorptive extraction combined with gas chromatography and mass spectrometry has been developed and validated for the determination of broad polarity spectrum emerging pollutants, ethyl paraben, butyl paraben, diethyl phthalate, dibutyl phthalate, lidocaine, prilocaine, triclosan, and bisphenol A in various aqueous samples. Some important parameters of fabric phase sorptive extraction such as extraction time, matrix pH, stirring speed, type and volume of desorption solvent were investigated and optimized. Calibration curves were obtained in the concentration range 0.05-500 ng/mL. Under the optimum conditions, the limits of detection were in the range 0.009 -0.021 ng/mL. This method was validated by analyzing the compounds in spiked aqueous samples at different levels with recoveries of 93 to 99% and relative standard deviations of <6%. The developed method was applied for the determination of the emerging contaminants in tap water, municipal water, ground water, sewage water, and sludge water samples. The results demonstrate that fabric phase sorptive extraction has great potential in the preconcentration of trace analytes in complex matrix.


Assuntos
Extração em Fase Sólida , Poluentes Químicos da Água/análise , Adsorção , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
3.
Molecules ; 24(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871257

RESUMO

Fabric phase sorptive extraction, an innovative integration of solid phase extraction and solid phase microextraction principles, has been combined with gas chromatography-mass spectrometry for the rapid extraction and determination of nineteen organochlorine pesticides in various fruit juices and water samples. FPSE consolidates the advanced features of sol-gel derived extraction sorbents with the rich surface chemistry of cellulose fabric substrate, which could extract the target analytes directly from the complex sample matrices, substantially simplifying the sample preparation operation. Important FPSE parameters, including sorbent chemistry, extraction time, stirring speed, type and volume of back-extraction solvent, and back-extraction time have been optimized. Calibration curves were obtained in a concentration range of 0.1⁻500 ng/mL. Under optimum conditions, limits of detection were obtained in a range of 0.007⁻0.032 ng/mL with satisfactory precision (RSD < 6%). The relative recoveries obtained by spiking organochlorine pesticides in water and selected juice samples were in the range of 91.56⁻99.83%. The sorbent sol-gel poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) was applied for the extraction and preconcentration of organochlorine pesticides in aqueous and fruit juice samples prior to analysis with gas chromatography-mass spectrometry. The results demonstrated that the present method is simple, rapid, and precise for the determination of organochlorine pesticides in aqueous samples.


Assuntos
Sucos de Frutas e Vegetais/análise , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Calibragem , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Extração em Fase Sólida/normas , Microextração em Fase Sólida/métodos , Microextração em Fase Sólida/normas , Água/química
4.
J Sep Sci ; 42(4): 862-870, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600583

RESUMO

In the present work, a high-efficiency and solvent minimized microextraction technique, fabric phase sorptive extraction followed by gas chromatography and mass spectrometry analysis is proposed for the rapid determination of four organophosphorus pesticides (terbufos, malathion, chlorpyrifos, and triazofos) in vegetable samples including beans, tomato, brinjal, and cabbage. Fabric phase sorptive extraction combines the beneficial features of sol-gel derived microextraction sorbents with the rich surface chemistry of cellulose fabric substrate, which collectively form a highly efficient microextraction system. Fabric phase sorptive extraction membrane, when immersed directly into the sample matrix, may extract target analytes even when high percentage of matrix interferents are present. The technique also greatly simplifies sample preparation workflow. Most important fabric phase sorptive extraction parameters were investigated and optimized. The developed method displayed good linearity over the concentration range 0.5-500 ng/g. Under optimum experimental conditions, the limits of detection were found in the range of 0.033 to 0.136 ng/g. The relative standard deviations for the extraction of organophosphorus pesticides were < 5%. Subsequently, the new method was applied to beans, tomato, brinjal, and cabbage samples. The results from the real sample analysis indicate that the method is green, rapid, and economically feasible for the determination of organophosphorus pesticides in vegetable samples.


Assuntos
Compostos Organofosforados/análise , Praguicidas/análise , Microextração em Fase Sólida , Verduras/química , Adsorção , Cromatografia Gasosa-Espectrometria de Massas , Propriedades de Superfície
5.
Crit Rev Anal Chem ; 46(5): 424-42, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26939618

RESUMO

The analysis of drugs in various biological fluids is an important criterion for the determination of the physiological performance of a drug. After sampling of the biological fluid, the next step in the analytical process is sample preparation. Sample preparation is essential for isolation of desired components from complex biological matrices and greatly influences their reliable and accurate determination. The complexity of biological fluids adds to the challenge of direct determination of the drug by chromatographic analysis, therefore demanding a sample preparation step that is often time consuming, tedious and frequently overlooked. However, direct online injection methods offer the advantage of reducing sample preparation steps and enabling effective pre-concentration and clean-up of biological fluids. These procedures can be automated and therefore reduce the requirements for handling potentially infectious biomaterial, improve reproducibility, and minimize sample manipulations and potential contamination. This review is focused on the discovery and development of high-performance liquid chromatography (HPLC) and gas chromatography (GC) with different detectors. The drugs covered in this review are antiepileptics, antidepressant (AD), and quinolones. The application of these methods for determination of these drugs in biological, environmental and pharmaceutical samples has also been discussed.


Assuntos
Anticonvulsivantes/análise , Antidepressivos/análise , Poluentes Ambientais/análise , Poluentes Ambientais/química , Preparações Farmacêuticas/química , Quinolonas/análise , Animais , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Humanos
6.
J Sep Sci ; 39(5): 923-31, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26683135

RESUMO

A simple and rapid method using microextraction by packed sorbent coupled with gas chromatography and mass spectrometry has been developed for the analysis of five phthalates, namely, diethyl phthalate, benzyl-n-butyl phthalate, dicyclohexyl phthalate, di-n-butyl phthalate, and di-n-propyl phthalate, in cold drink and cosmetic samples. The various parameters that influence the microextraction by packed sorbent performance such as extraction cycle (extract-discard), type and amount of solvent, washing solvent, and pH have been studied. The optimal conditions of microextraction using C18 as the packed sorbent were 15 extraction cycles with water as washing solvent and 3 × 10 µL of ethyl acetate as the eluting solvent. Chromatographic separation was also optimized for injection temperature, flow rate, ion source, interface temperature, column temperature gradient and mass spectrometry was evaluated using the scan and selected ion monitoring data acquisition mode. Satisfactory results were obtained in terms of linearity with R(2) >0.9992 within the established concentration range. The limit of detection was 0.003-0.015 ng/mL, and the limit of quantification was 0.009-0.049 ng/mL. The recoveries were in the range of 92.35-98.90% for cold drink, 88.23-169.20% for perfume, and 88.90-184.40% for cream. Analysis by microextraction by packed sorbent promises to be a rapid method for the determination of these phthalates in cold drink and cosmetic samples, reducing the amount of sample, solvent, time and cost.


Assuntos
Bebidas/análise , Cosméticos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Ftálicos/análise , Ácidos Ftálicos/isolamento & purificação , Microextração em Fase Sólida/métodos , Adsorção , Microextração em Fase Sólida/instrumentação
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