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1.
J Sep Sci ; 39(2): 427-32, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26592730

RESUMO

The rapid screening of trace levels of short-chain chlorinated paraffins in various aqueous samples was performed by a simple and reliable procedure based on vortex-assisted liquid-liquid microextraction combined with gas chromatography and electron capture negative ionization mass spectrometry. The optimal vortex-assisted liquid-liquid microextraction conditions for 20 mL water sample were as follows: extractant 400 µL of dichloromethane; vortex extraction time of 1 min at 2500 × g; centrifugation of 3 min at 5000 × g; and no ionic strength adjustment. Under the optimum conditions, the limit of quantitation was 0.05 µg/L. Precision, as indicated by relative standard deviations, was less than 9% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was above 91%. The vortex-assisted liquid-liquid microextraction with gas chromatography and electron capture negative ionization mass spectrometry method was successfully applied to quantitatively extract short-chain chlorinated paraffins from samples of river water and the effluent of a wastewater treatment plant, and the concentrations ranged from 0.8 to 1.6 µg/L.

2.
Ecotoxicology ; 25(2): 302-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26589946

RESUMO

Benzophenone-3 (BP-3) is a widely used organic UV-filter compound. Despite the frequent occurrence of BP-3 in aquatic environments, little is known about its effect on fish behavior. The aim of this study was to investigate the endocrine disrupting effects of BP-3 in male fighting fish (Betta splendens) with a focus on agonistic behavior. Male fighting fish were exposed to 10, 100, and 1000 µg/L BP-3, as well as a solvent control (0.1% ethanol) and a positive control (100 ng/L 17α-ethynylestradiol, EE2), for 28 days. At the beginning and the end of exposure, standard length and body mass of the fish were measured for calculating the condition factor (CF). In addition, spontaneous swimming activity (total distance moved) and agonistic behavior (maximum velocity and duration of opercular display in front of a mirror) were also quantified. At the end of exposure, the fish gonads were sampled for gonadosomatic index (GSI) measurement and histology. After the exposure, CF was significantly decreased in the 1000 µg/L BP-3 groups. Spontaneous swimming activity was not affected. However, maximum velocity was significantly reduced in the EE2 and 1000 µg/L BP-3 treatments; duration of opercular display was significantly decreased in the EE2 and 10 and 1000 µg/L BP-3 treatments. GSI was not significantly different between groups. There was a slight but statistically significant decrease of relative proportion of mature spermatozoa in testicular tissue in the 100 µg/L BP-3 treatment. Collectively, our results demonstrate that BP-3 can disrupt agonistic behavior of male fighting fish, indicating the endocrine disrupting activity of this compound.


Assuntos
Comportamento Agonístico/efeitos dos fármacos , Benzofenonas/toxicidade , Disruptores Endócrinos/toxicidade , Perciformes/fisiologia , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Masculino
3.
Anal Bioanal Chem ; 402(4): 1723-30, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22139524

RESUMO

A simple and solvent-minimized procedure for the determination of six commonly found synthetic polycyclic musks in aqueous samples using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled with gas chromatography-mass spectrometry (GC-MS) is described. The parameters affecting the extraction efficiency of analytes from water samples were systematically investigated. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of isopropyl alcohol (as a dispersant) and 10 µL of carbon tetrachloride (as an extractant) into 10 mL of water containing 0.5 g of sodium chloride in a conical-bottom glass tube. After ultrasonication for 1.0 min and centrifugation at 5,000 rpm (10 min), the sedimented phase 1.0 µL was directly injected into the GC-MS system. The limits of quantitation (LOQs) were less than 0.6 ng/L. The precision for these analytes, as indicated by relative standard deviations (RSDs), was less than 11% for both intra- and interday analysis. Accuracy, expressed as the mean extraction recovery, was between 71 and 104%. Their total concentrations were determined in the range from 8.3 to 63.9 ng/L in various environmental samples by using a standard addition method.


Assuntos
Ácidos Graxos Monoinsaturados/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Odorantes/análise , Poluentes Químicos da Água/análise , Água/análise , Ácidos Graxos Monoinsaturados/isolamento & purificação , Sensibilidade e Especificidade , Ultrassom/métodos , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/isolamento & purificação
4.
Anal Bioanal Chem ; 402(6): 2209-16, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22222914

RESUMO

A simple sample pretreatment technique, dispersive micro-solid phase extraction, was applied for the extraction of N-nitrosodimethylamine (NDMA) and other four N-nitrosamines (NAs) from samples of swimming pool water. The parameters affecting the extraction efficiency were systematically investigated. The best extraction conditions involved immersing 75 mg of carbon molecular sieve, Carboxen™ 1003 (as an adsorbent), in a 50-mL water sample (pH 7.0) containing 5% sodium chloride in a sample tube. After 20 min of extraction by vigorous shaking, the adsorbent was collected on a filter and the NAs desorbed by treatment with 150 µL of dichloromethane. A 10-µL aliquot was then directly determined by large-volume injection gas chromatography with chemical ionization mass spectrometry using the selected ion storage mode. The limits of quantitation were <0.9 ng/L. The precision for these analytes, as indicated by relative standard deviations, were <8% for both intra- and inter-day analyses. Accuracy, expressed as the mean extraction recovery, was between 62% and 109%. A preliminary analysis of swimming pool water samples revealed that NDMA was present in the highest concentration, in the range from n.d. to 100 ng/L.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Nitrosaminas/isolamento & purificação , Extração em Fase Sólida/métodos , Piscinas , Poluentes Químicos da Água/isolamento & purificação , Dimetilnitrosamina/análise , Dimetilnitrosamina/isolamento & purificação , Limite de Detecção , Nitrosaminas/análise , Água/análise , Poluentes Químicos da Água/análise
5.
J Sep Sci ; 35(16): 2122-30, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22899640

RESUMO

A rapid and solvent-free procedure for the determination of 4-tert-octylphenol and 4-nonylphenol isomers in aqueous samples is described. The method involves in-situ acetylation and microwave-assisted headspace solid-phase microextraction prior to their determination using gas chromatography-ion trap mass spectrometry operated in the selected ion storage mode. The dual experimental protocols to evaluate the effects of various derivatization and extraction parameters were investigated and the conditions optimized. Under optimized conditions, 300 µL of acetic anhydride mixed with 1 g of potassium hydrogencarbonate and 2 g of sodium chloride in a 20 mL aqueous sample were efficiently extracted by a 65 µm polydimethylsiloxane-divinylbenzene fiber that was located in the headspace when the system was microwave irradiated at 80 W for 5 min. The limits of quantitation were 5 and 50 ng/L for 4-tert-octylphenol and 4-nonylphenol isomers, respectively. The precision for these analytes, as indicated by relative standard deviations, were less than 8% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 74 to 88%. A standard addition method was used to quantitate 4-tert-octylphenol and 4-nonylphenol isomers, and the concentrations ranged from 120 to 930 ng/L in various environmental water samples.

6.
Food Chem ; 368: 130798, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34411854

RESUMO

Benzotriazole (BTRs) and benzothiazole (BTHs) derivatives are a group of high production volume chemicals with emerging health concern, which found in tea beverages raising potential risks for food safety and human health. The present work describes a simple method using a "green" deep eutectic solvent (DES) based-ultrasound-assisted liquid-phase microextraction (UALPME) to rapidly extract BTRs and BTHs from tea beverages, and then applying UHPLC-electrospray ionization (+)-quadrupole time-of-flight mass spectrometry for detection and quantification. To overcome the challenges related to different experimental conditions, a Factorial Multilevel Categoric Design and a Face Centered Central Composite Design were applied to screen and optimize the parameters for the DES-UALPME procedure, respectively. After optimization, the method was validated and shown to possess low limits of quantification (LOQs; 1.5-12 ng mL-1), high precision (3-13%), and satisfactory accuracy (65-107%). The developed method was then successfully applied for the analysis of some selected BTRs and BTHs in tea beverages.


Assuntos
Microextração em Fase Líquida , Benzotiazóis , Bebidas/análise , Cromatografia Líquida , Humanos , Limite de Detecção , Solventes , Espectrometria de Massas por Ionização por Electrospray , Chá , Triazóis
7.
J Chromatogr A ; 1681: 463443, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36088775

RESUMO

Benzophenone-type ultraviolet filters (BP-UVFs) are a group of emerging contaminants, which found in various environmental aqueous samples raising potential risks for public health concern and could bioaccumulate in the food chain. This study describes a simple and "green" method to rapidly analyze five BP-UVFs that are frequently found in surface water and in seawater samples. Dispersive solid-phase extraction (DSPE) using a zeolitic imidazolate framework­8 (ZIF-8) as the sorbent was applied to efficiently extract the BP-UVFs from aqueous samples, and they were then detected and quantified by UHPLC-electrospray ionization (+)-quadrupole time-of-flight mass spectrometry (UHPLC-ESI (+)-QTOF-MS). The ZIF-8 sorbent was synthesized by a green one-step mechanochemical process using water-assisted grinding and a stoichiometric reaction. The Box-Behnken Design coupled with the response surface method was applied to optimize the main DSPE extraction factors. The developed method was fully validated, showing low limits of quantification (LOQs; 0.3-20 ng L-1), satisfactory mean spiked recoveries (72-105%), and a high level of precision (3-9%). A preliminary analysis of the surface water and seawater samples revealed that 2-hydroxy-4-methoxybenzophenone (BP-3) was the most common BP-UVF present in our aquatic environment, likely due to its widespread applications and slow rate of degradation.


Assuntos
Poluentes Químicos da Água , Zeolitas , Benzofenonas/análise , Extração em Fase Sólida/métodos , Água , Poluentes Químicos da Água/análise , Zeolitas/química
8.
Environ Pollut ; 284: 117530, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34261225

RESUMO

Benzotriazole (BTRs) and benzothiazole (BTHs) derivatives have been classified as high production volume pollutants of emerging concern. The present work describes a rapid and simple process using an eco-friendly deep eutectic solvent (DES) based-ultrasound-assisted liquid-liquid microextraction (DES-UALLME) technique to effectively extract five BTRs and four BTHs in human urine samples, and then applying ultrahigh-performance liquid chromatography and electrospray ionization (+)-quadrupole time-of-flight mass spectrometry (UHPLC-ESI(+)-QTOF-MS) for their detection and quantification. DESs are a group of novel "green" solvents, and their applications in sample pretreatment are appropriate for the requirements for green chemistry, environmental protection and sustainable development. Furthermore, to overcome the challenges related to different experimental conditions, multivariate experimental design approaches conducted by means of a multilevel categorical design and a Box-Behnken Design were applied to screen and optimize parameters that have significant influences on the extraction efficiency of DES-UALLME. After optimization, the method was validated and shown to possess low limits of quantitation (LOQs; 0.4 - 9 ng mL-1), high precision (3-12%), and high accuracy (mean spiked recoveries; 80-101%). The developed method was then successfully applied for the analysis of BTRs and BTHs in human urine samples. Interestingly, 5,6-dimethyl-1H-benzotriazole (XTR) was detected in almost all of the urine samples, which correlates with its high production and widely applications in industry processes and consumer products in Taiwan. These target analytes could potentially be used as biomarkers to assess exposure of BTRs and BTHs in biomonitoring programs and studies.


Assuntos
Microextração em Fase Líquida , Benzotiazóis , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Limite de Detecção , Espectrometria de Massas , Solventes , Taiwan , Triazóis
9.
RSC Adv ; 11(38): 23607-23615, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35479786

RESUMO

This work describes a rapid solvent-minimized process to effectively determine four common paraben preservatives (methyl-, ethyl-, propyl- and butyl-paraben) in surface water samples. The method involved the use of a combination of a novel ultrasound-assisted simultaneous-silylation within dispersive liquid-liquid microextraction (UASS-DLLME) with detection by gas chromatography-tandem mass spectrometry (GC-MS/MS). To overcome the challenges related to the different experimental conditions, multivariate experimental design approaches conducted by means of a multilevel categorical design and a Box-Behnken design were utilized to screen and optimize parameters that have significant influences on the efficiency of silylation and extraction. The method was then validated and shown to provide low limits of quantitation (LOQs; 1-5 ng L-1), high precision (3-11%), and satisfactory mean spiked recoveries (accuracy; 79-101%). Upon analyzing samples of surface water obtained from the field, we found that, in total, there was a relatively high concentration of the target parabens ranging from 200 to 1389 ng L-1. The sources of the elevated levels of these parabens may be from the release of untreated municipal wastewater in this region, and also due to the widespread application of parabens in personal care and food products.

10.
J Hazard Mater ; 401: 123383, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32763686

RESUMO

This work describes a simple and environmental-friendly method for the simultaneous determination of five benzotriazole derivatives (BTRs) and four benzothiazole derivatives (BTs) that are frequently found in surface water. The target analytes were efficiently extracted from water samples using a "green" deep eutectic solvent (DES) as the extraction solvent based- ultrasound-assisted emulsification microextraction (DES-USAEME), and their determination were performed by ultrahigh-performance liquid chromatography and electrospray ionization (+)-quadrupole time-of-flight mass spectrometry (UHPLC-ESI(+)-QToF-MS). The DES was composed of a mixture of choline chloride and phenol (molar ratio 1:2). The DES-USAEME factors were optimized by a Box-Behnken Design coupled response surface methodology. The developed method was validated, providing limits of quantitation (LOQs; 02 µg L-1), high precisions (1-8%), and satisfactory mean spiked recoveries (72-104 %). Relatively high total concentrations of the target analytes were found in samples collected from a reservoir (47.2-101.3 µg L-1), which may have been released from tire-wear particles and scrap tires from buses and old tires that were strung alongside the shuttle boats to prevent the boats from coming into contact with each other or from impacting against the dock during docking. This is the first study on the occurrence of BTRs and BTs in reservoir samples.

11.
Food Chem ; 333: 127516, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683261

RESUMO

Benzotriazoles (BTRs) and benzothiazoles (BTs) are two groups of emerging concern and high production volume contaminants. Via the biomagnification of the food web, they could jeopardize human health. In this work, rapid determining the presence of five BTRs and two BTs in marketed fish was performed by a novel double-vortex-ultrasonic assisted matrix solid-phase dispersion (DVUA-MSPD) and UHPLC-electrospray ionization (+)-quadrupole time-of-flight mass spectrometry detection. Unlike traditional MSPD, we simplified the method without the use of mortar/pestle and SPE-column procedures. The DVUA-MSPD factors were screened by a multilevel categorical design, and then optimized by Box-Behnken Design plus with response surface methodology. The limits of quantification were 0.15-2 ng g-1 (dry weight). The satisfactory average recovery ranged from 70% to 93% with RSDs less than 9%. The developed method was successfully applied for the rapid determination of selected BTRs and BTs in fish samples at trace-level.


Assuntos
Benzotiazóis/química , Peixes/metabolismo , Extração em Fase Sólida/métodos , Animais , Benzotiazóis/análise , Benzotiazóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Ultrassom
12.
RSC Adv ; 10(58): 35557-35564, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-35515645

RESUMO

The extensive use of preservatives during the growth, transport and storage of vegetables has been a concern because of their known or suspected toxicity that jeopardizes human health. This paper reports the development of a technique that rapidly determines the presence of five paraben preservative residues in leafy vegetables using double-vortex-assisted matrix solid-phase dispersion (DVA-MSPD) and UHPLC-electrospray ionization(-)-quadrupole time-of-flight mass spectrometry detection. We simplified the original MSPD technique by eliminating the use of mortar/pestle and SPE-column procedures. The DVA-MSPD factors were screened by a multilevel categorical design, and then optimized by Box-Behnken Design plus response surface methodology. The limits of quantification were 1.2-1.8 ng g-1 (dry weight). The satisfactory average recoveries were 85-104% with RSDs less than 10%. The developed method was successfully employed for the rapid determination of selected paraben residues at trace-level in leafy vegetable samples.

13.
Environ Pollut ; 267: 115475, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33254616

RESUMO

Exposure to environmental chemicals with oestrogenic effects has been associated with the development of endometrial cancer (EMCa). EMCa has become the most commonly diagnosed cancer of the female genital tract. To further understand the potential association between exposure to environmental endocrine disruptors and the occurrence of EMCa, we performed a case-control study between 2011 and 2014. We aimed to detect and compare concentrations of a known hormone disruptor, alkylphenol, between women diagnosed with either EMCa or uterine leiomyoma, and those who did not have either of these. Subjects were women diagnosed with either EMCa or uterine leiomyoma (LM) and healthy controls. A structured questionnaire was administered to collect information on lifestyle and health status. Gas chromatography/mass spectrometry was used to measure urinary NP and OP concentrations in participants. Multiple regression analysis was used to examine the association between exposure and outcomes. Overall, 397 women were recruited, including 49 with EMCa, 247 with LM, and 101 controls. Among them, 73.6% showed detectable levels of NP and 61.0% showed detectable levels of OP. The EMCa group had a significantly higher NP concentration than the control group. Higher OP concentrations were also found in participants with EMCa than those with LM and controls. In addition, women in the upper tertile of the NP group had a significantly increased risk of EMCa occurrence (odds ratio [95% confidence interval] = 4.47 [1.69-11.84] for EMCa vs. control). The same was found in the group of women with more than the median level of OP (odds ratio [95% confidence interval] = 4.32 [2.01-9.30] for EMCa vs. LM). Stratification of pre- and post-menopausal groups resulted in a similar association. The results show that NP/OP exposure is associated with EMCa. Further investigations and exposure minimisation are suggested.


Assuntos
Disruptores Endócrinos , Neoplasias do Endométrio , Estudos de Casos e Controles , Neoplasias do Endométrio/induzido quimicamente , Neoplasias do Endométrio/epidemiologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Razão de Chances
14.
Anal Bioanal Chem ; 395(7): 2325-34, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19784832

RESUMO

An efficient microwave-assisted extraction (MAE) procedure coupled to gas chromatography-mass spectrometry (GC-MS) with electron impact (EI) and chemical ionization (CI) has been developed to determine five organophosphate flame retardants (OPFRs) in marine and river sediments. The effects of various operating parameters on the quantitative extraction of the OPFRs through MAE were systematically investigated. Selected OPFRs were extracted from the sediments through MAE using 40 mL of acetone at 120 degrees C for 20 min. The limits of quantitation ranged from 0.1 to 0.4 ng/g (dry weight) in 2 g of the sediment samples. Moreover, as the chlorinated alkyl phosphates present no molecular ions in EI, GC-MS with furan-CI (furan-CI) was applied to confirm their determination in complex environmental samples. The recoveries of the selected OPFRs in spiked sediment samples ranged from 62% to 106% (relative standard derivation, 1-11%). The total concentrations of the selected OPFR residues in marine and river sediments ranged from 1.0 to 12.6 ng/g.

15.
RSC Adv ; 9(66): 38669-38676, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35540236

RESUMO

Rapid screening of two microcystins (i.e., microcystin-YR (MC-YR) and microcystin-LR (MC-LR)) in surface water samples was performed by a simple and eco-friendly procedure using deep eutectic solvent-based vortex-assisted liquid-liquid microextraction (DES-based VALLME) combined with ultrahigh-performance liquid chromatography and electrospray ionization (+)-quadrupole time-of-flight mass spectrometry (UHPLC-ESI(+)-qTOF-MS) detection. To obtain an efficient water-miscible DES, choline chloride and phenol at a molar ratio of 1 : 2 were used as an extractant for VALLME. To optimize factors of DES-based VALLME, response surface design alongside Box-Behnken design was used. The limits of quantitation (LOQs) were 0.5 ng mL-1 and 0.4 ng mL-1 for MC-YR and MC-LR, respectively, which is sensitive enough to meet the World Health Organization (WHO) maximum guideline level for MC-LR in water of 1.0 ng mL-1. Moreover, satisfactory precision with relative standard deviations (RSD) for both intra- and inter-day analysis lower than 11%, and trueness (also known as mean extraction recovery) ranged from 85.5 to 113% based on the ICH method validation guideline.

16.
J Chromatogr A ; 1605: 460367, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31402109

RESUMO

A reliable and straightforward method was developed for the rapid determination of nine parabens (methyl-, ethyl-, propyl-, butyl-, isopropyl-, isobutyl-, pentyl-, hexyl-, and benzyl-parabens) in indoor dust by a mortar/pestle-free and column-free dual-vortex-assisted matrix solid-phase dispersion (DVA-MSPD) technique. After that, they were determined by isotope-dilution ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-qTOF-MS, or called UHPLC-HRMS) and operating in negative electrospray ionization mode. Optimization of the DVA-MSPD was done using Box-Behnken Design along with response surface methodology. Validation was done by measuring and calculating selectivity, limits of detection (LOD), limits of quantitation (LOQs), precision and trueness (accuracy) of intra- and inter-day analysis. The LOQs of the method ranged from 0.9 to 2.8 ng/g. High precisions for both intra- and inter-day analysis were obtained ranging from 1 to 8%. Excellent trueness (or mean extraction recovery) varied from 93 to 104%. The DVA-MSPD combined with isotope-dilution UHPLC-qTOF-MS was successfully applied to determine parabens in indoor dust samples from office rooms and private houses, and the total concentrations ranged from 55 to 686 ng/g.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Cromatografia Líquida de Alta Pressão/métodos , Poeira/análise , Espectrometria de Massas/métodos , Parabenos/análise , Extração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Técnicas de Diluição do Indicador , Isótopos , Limite de Detecção
17.
Food Chem Toxicol ; 46(2): 803-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17950972

RESUMO

This paper describes a simple and sensitive method for determining alkylphenols namely 4-tert-octylphenol (4-t-OP) and the isomers of 4-nonylphenol (4-NPs) present in various types of baby-food purees. The method involves extracting a sample with n-hexane for 1h using a modified Nielson-Kryger steam distillation extraction system and then identifying and quantitating the alkylphenols using a gas chromatography-mass spectrometry (GC-MS) operated in the selected ion monitoring (SIM) mode. The extraction conditions were evaluated at various values of pH of the sample solution. The limits of quantitation for this method were 0.2 ng/g from 1.0 g (wet weight) samples of 4-t-OP and the 4-NPs. The intra- and interbatch precisions and accuracies were also determined. The precision, in terms of the relative standard deviation (RSD), were less than 8%. Most of the recoveries of the alkylphenols from various spiked samples exceeded 60%, while the values of RSD ranged from 1% to 10%. Alkylphenol residues were detected in baby-food purees at concentrations of up to 19 ng/g (wet weight) for 4-t-OP and up to 21 ng/g (wet weight) for the 4-NPs.


Assuntos
Estrogênios não Esteroides/análise , Análise de Alimentos/métodos , Alimentos Infantis/análise , Fenóis/análise , Cromatografia Gasosa-Espectrometria de Massas , Taiwan
18.
Chemosphere ; 72(6): 863-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18499225

RESUMO

To establish their environmental concentrations and to support surface water protection programs, we have undertaken a preliminary study of the concentrations of selected acidic and neutral pharmaceutical residues (clofibric acid, ketoprofen, ibuprofen, diclofenac and carbamazepine) in Taiwanese river and wastewater samples. These pharmaceutical residues were extracted from the water samples through the Oasis HLB solid-phase extraction (SPE). The analytes were then identified and quantified using liquid chromatography-ion trap mass spectrometry with dual-polarity electrospray ionization in the product ion scan mode. The limits of quantification (LOQs) ranged between 0.5 and 20 ngl(-1) for 250 ml samples of water. We investigated the intra- and interbatch precision and accuracy at two levels of concentration. The selected analytes were detected at concentrations ranging from <0.5 to 960 ngl(-1) in wastewater treatment plant effluents and river water samples.


Assuntos
Monitoramento Ambiental/métodos , Preparações Farmacêuticas/análise , Rios/química , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão/métodos , Monitoramento Ambiental/instrumentação , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taiwan
19.
J Pharm Biomed Anal ; 149: 572-576, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29197299

RESUMO

An analytical method that utilizes isotope-dilution gas chromatography-mass spectrometry (ID-GC-MS) coupled with injection-port butylation was developed. The method was validated, and confirmed to be able to determine the presence of three commonly detected endocrine-disrupting chemicals (EDCs: 4-tert-octylphenol (4-t-OP), 4-nonylphenols (4-NPs) and bisphenol A (BPA)) in human urine with high precision and accuracy. After sample preparation by solid-phase extraction, the extract was introduced into GC-MS via injection-port butylation. The butylated target analytes were identified and quantified by using ion-trap mass spectrometry operating in the selected-ion-storage mode, and employing the measurement of peak area ratios of the butylated target analytes and labeled-analogues in the samples and calibration standards. The labeled-analogues were also used to correct the variations associated with the analysis and matrix effect. The limits of quantitation (LOQs) ranged from 0.1 to 0.3ng/mL. High precisions for both intra- and inter-day analysis ranged from 1 to 6%, and excellent accuracy (mean recovery) ranged from 92 to 105% on two concentration levels. In human urine, the total concentrations of three selected EDCs varied from 1.28 to 7.14ng/mL. 4-NPs were detected within all collected samples. The developed method allows accurate analysis of trace-level of EDCs in urine, and these target EDCs could act as useful biomarkers to assess exposure in biomonitoring studies and programs.


Assuntos
Disruptores Endócrinos/urina , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Adulto , Compostos Benzidrílicos/toxicidade , Compostos Benzidrílicos/urina , Biomarcadores/urina , Calibragem , Monitoramento Ambiental/instrumentação , Feminino , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Voluntários Saudáveis , Humanos , Isótopos/química , Fenóis/toxicidade , Fenóis/urina , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos , Tiocarbamatos/química , Adulto Jovem
20.
J Pharm Biomed Anal ; 150: 469-473, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29291588

RESUMO

An analytical method that utilizes isotope-dilution ultrahigh-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS or called UHPLC-HRMS) was developed, and validated to be highly precise and accurate for the detection of nine parabens (methyl-, ethyl-, propyl-, isopropyl-, butyl-, isobutyl-, pentyl-, hexyl-, and benzyl-parabens) in human urine samples. After sample preparation by ultrasound-assisted emulsification microextraction (USAEME), the extract was directly injected into UHPLC-HRMS. By using negative electrospray ionization in the multiple reaction monitoring (MRM) mode and measuring the peak area ratios of both the natural and the labeled-analogues in the samples and calibration standards, the target analytes could be accurately identified and quantified. Another use for the labeled-analogues was to correct for systematic errors associated with the analysis, such as the matrix effect and other variations. The limits of quantitation (LOQs) were ranging from 0.3 to 0.6 ng/mL. High precisions for both repeatability and reproducibility were obtained ranging from 1 to 8%. High trueness (mean extraction recovery, or called accuracy) ranged from 93 to 107% on two concentration levels. According to preliminary results, the total concentrations of four most detected parabens (methyl-, ethyl-, propyl- and butyl-) ranged from 0.5 to 79.1 ng/mL in male urine samples, and from 17 to 237 ng/mL in female urine samples. Interestingly, two infrequently detected pentyl- and hexyl-parabens were found in one of the male samples in this study.


Assuntos
Cromatografia Líquida/métodos , Parabenos/análise , Técnica de Diluição de Radioisótopos , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Adulto , Calibragem , Cromatografia Líquida/normas , Feminino , Humanos , Limite de Detecção , Masculino , Estrutura Molecular , Técnica de Diluição de Radioisótopos/normas , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/normas , Espectrometria de Massas em Tandem/normas , Urinálise , Urina/química , Fluxo de Trabalho , Adulto Jovem
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