Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Ecotoxicol Environ Saf ; 242: 113845, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35809397

RESUMEN

Pharmaceutical drugs in the aquatic medium may pose significant risk to non-target organisms. In this study, the potential toxicity of a mixture of three compounds commonly detected in marine waters (ibuprofen, ciprofloxacin and flumequine) was assessed, by studying bioaccumulation, oxidative stress and neurotoxicity parameters (catalase CAT, superoxide dismutase SOD, glutathione reductase GR, glutathione S-transferase GST, lipid peroxidation LPO, glutathione peroxidase GPX, metallothionein MT and acetylcholinesterase AChE) in the clam Scrobicularia plana. Temporal evolution of selected endpoints was evaluated throughout an exposure period (1, 7 and 21 days) followed by a depuration phase. The accumulation of all drugs was fast, however clams showed the ability to control the internal content of drugs, keeping their concentration constant throughout the exposure and reducing their content after 7 days of depuration. The induction of biochemical alterations (SOD, CAT, LPO, MT, AChE) was observed in gills and digestive gland probably related to an imbalance in the redox state of clams as a consequence of the exposure to the drug mixture. These alterations were also maintained at the end of the depuration week when the high levels of SOD, CAT, GST and LPO indicated the persistence of oxidative stress and damage to lipids despite the fact that clams were no longer exposed to the mixture.


Asunto(s)
Bivalvos , Contaminantes Químicos del Agua , Acetilcolinesterasa/metabolismo , Animales , Bioacumulación , Biomarcadores/metabolismo , Bivalvos/metabolismo , Catalasa/metabolismo , Glutatión Reductasa/metabolismo , Glutatión Transferasa/metabolismo , Peroxidación de Lípido , Estrés Oxidativo , Preparaciones Farmacéuticas , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/toxicidad
2.
J Environ Manage ; 297: 113314, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34298344

RESUMEN

In this work the presence of different pharmaceuticals at Doñana National Park (Spain) and their main entry sources (input source or entry points) have been stated over the 2011-2016 years period. Twenty-three selected pharmaceuticals (corresponding to eight therapeutic families) were evaluated in crayfish and water samples from Doñana National Park (Spain) (six sampling points selected in order to cover different possible pollution sources into and surrounding the Park). The multiresidue determination was carried out using enzymatic-microwave assisted extraction prior to high performance liquid chromatography mass spectrometry detection. Sulphonamides (sulfadiazine, sulfamerazine, sulfamethazine, and sulfamethoxazole); trimethoprim, an antibiotic that is frequently co-administered with sulfamethoxazole; amphenicols (chloramphenicol, florfenicol and thiamphenicol); fluoroquinolones (ciprofloxacin, enrofloxacin, flumequine, danofloxacin, gatifloxacin, norfloxacin, marbofloxacin and grepafloxacin); penicillins (amoxicillin); tetracyclines (chlortetracycline and oxytetracycline); non-steroidal anti-inflammatory drugs (salicylic acid and ibuprofen); beta-blocker drugs (atenolol); and antiepileptics (carbamazepine) were analysed. Ciprofloxacin, ibuprofen, salicylic acid, flumequine, and carbamazepine were detected and/or quantified at some of the selected sampling points. A clear ecotoxicological risk to the ecosystem was demonstrated from the occurrence of ciprofloxacin in samples obtained after the punctual and massive presence of people inside the Park. Furthermore, flumequine and carbamazepine have been detected in Procambarus clarkii specimens in concentrations around 30 ng g-1 and 14 ng g-1, respectively, and their occurrence in the specimens could indicate the persistence of the discharge sources. The main source of pharmaceuticals into the Park might be the livestock farming activities, and the influence of urban wastewaters from surrounding villages does not seem to be very important.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Animales , Astacoidea , Biota , Ecosistema , Monitoreo del Ambiente , Humanos , Parques Recreativos , España , Contaminantes Químicos del Agua/análisis
3.
Anal Bioanal Chem ; 412(25): 6811-6822, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32696068

RESUMEN

A comparative study on the extraction efficiency of five non-steroidal anti-inflammatories was carried out using three different electromembrane extraction (EME) devices with different geometries. The employed setups were (a) a hollow fiber configuration (HF-EME), (b) a microfluidic device that allows working in semi-dynamic mode (µF-EME), and (c) a static miniaturized flat membrane device (FM-EME). Each system was applied to the extraction of salicylic acid (SAC), ketoprofen (KTP), naproxen (NAX), diclofenac (DIC), and ibuprofen (IBU) and subsequent determination by high-performance liquid chromatography with UV and fluorescence detection (HPLC/UV-DAD-FLD). Voltage, pH composition, and extraction time were optimized for all devices. Additionally, volume ratio was investigated for HF-EME and FM-EME and flow rate for the microfluidic device. HF-EME provides the best result in terms of sensitivity with a limit of detection (LOD) between 0.1 and 1.5 ng mL-1 for SAC and KTP, respectively, while LODs for µF-EME were between 100 ng mL-1 and 400 ng mL-1 for SAC and DIC, respectively; however, a lower amount of sample was required. Finally, the obtained results, in terms of enrichment factors and extraction recoveries, were discussed to establish the advantages and disadvantages of each device. The proposed EME methods were successfully applied to the determination of the target analytes in fortified human urine samples. Graphical abstract.


Asunto(s)
Antiinflamatorios no Esteroideos/orina , Membranas Artificiales , Cromatografía Líquida de Alta Presión/métodos , Humanos , Concentración de Iones de Hidrógeno , Límite de Detección , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta/métodos
4.
Anal Bioanal Chem ; 408(6): 1615-21, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26753971

RESUMEN

To our knowledge, for the first time an electromembrane extraction combined with a high-performance liquid chromatography procedure using diode-array detection has been developed for the determination of five of the most widely used parabens: ethyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, butyl 4-hydroxybenzoate, isobutyl 4-hydroxybenzoate, and benzyl 4-hydroxybenzoate. Parabens were extracted from pH 4 aqueous sample solutions with use of an Accurel® S6/2 polypropylene hollow fiber that supports a liquid membrane of 1-octanol to a pH 12 aqueous acceptor solution placed inside the lumen of the hollow fiber. An electric current of 30 V was applied over the supported liquid membrane by means of platinum wires placed in the donor and acceptor phases. Parabens were extracted in 40 min with enrichment factors in the 30-49 range. The procedure has detection limits between 0.98 and 1.43 µg L(-1). The method was applied to the determination of parabens in surface environmental waters with excellent results.

5.
Anal Chim Acta ; 1316: 342868, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-38969413

RESUMEN

BACKGROUND: In recent decades, green chemistry has been focusing on the adaptation of different chemical methods towards environmental friendliness. Sample preparation procedures, which constitute a fundamental step in analytical methodology, have also been modified and implemented in this direction. In particular, electromembrane extraction (EME) procedures, which have traditionally used plastic supports, have been optimized towards greener approaches through the emergence of alternative materials. In this regard, biopolymer-based membranes (such as agarose or chitosan) have become versatile and very promising substitutes to perform these processes. RESULTS: Different green metric tools (Analytical Eco-Scale, ComplexGAPI and AGREEprep have been applied to study the evolution of solid supports used in EME from nanostructured tissues and polymer inclusion membranes to agar films and chitosan flat membranes. The main goal is to evaluate the usage of these new biomaterials in the analytical procedure to quantify their environmental impact in the frame of Green Analytical Chemistry (GAC). In addition, both RGB model and BAGI metrics have been employed to study the sustainability of the whole procedure, including not only greenness, but also analytical performance and feasibility aspects. Results obtained after the performance of the mentioned metrics have demonstrated that the most efficient and environmentally friendly analytical methods are based on the use of chitosan supports. This improvement is mainly due to the chemical nature of this biopolymer as well as to the removal of organic solvents. SIGNIFICANCE: This work highlights the advantages of biodegradable materials employment in EME procedures to achieve green analytical methodologies. These materials also contribute to raise the figure of merits regarding to the quantification parameters in a wide range of applications compared to classical supports employed in EME, thus enhancing sustainability of procedures.

6.
Anal Bioanal Chem ; 405(8): 2575-84, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23307130

RESUMEN

For the first time, an electromembrane extraction combined with a HPLC procedure using diode array and fluorescence detection has been developed for the determination of seven widely used fluoroquinolones (FQs): marbofloxacin, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, gatifloxacin and grepafloxacin. The drugs were extracted from acid aqueous sample solutions (pH 5), through a supported liquid membrane consisting of 1-octanol impregnated in the walls of a S6/2 Accurel® polypropylene hollow fiber, to an acid (pH 2) aqueous acceptor solution inside the lumen of the hollow fiber. The main operational parameters were optimized, and extractions were carried out in 15 min using a potential of 50 V. Enrichment factors of 40-85 have been obtained using only 15 min of extraction time versus 330 min used in a previously proposed hollow-fiber liquid-phase microextraction procedure. The procedure allows low detection and quantitation limits of 0.005-0.07 and 0.007-0.15 µg L(-1), respectively. The proposed method was successfully applied to the FQs analysis in urban wastewaters.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Fluoroquinolonas/análisis , Fluoroquinolonas/aislamiento & purificación , Microextracción en Fase Líquida/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Concentración de Iones de Hidrógeno , Límite de Detección
7.
Membranes (Basel) ; 13(3)2023 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-36984713

RESUMEN

A chitosan biopolymeric membrane was successfully used as a support in a green electromembrane extraction procedure for the simultaneous and selective extraction of seven parabens and three fluoroquinolones in the presence of three non-steroidal anti-inflammatory drugs. The optimal experimental conditions (10 mL donor phase and 50 µL acceptor phase, pH 10 in both phases; 80 V of applied voltage during 15 min of extraction time) were determined, providing high enrichment factors for six of the studied parabens (EF ≥ 90) and the three fluoroquinolones (EF ≥ 50). Wide linear concentration ranges (0.5-500 µg L-1), good linearity (>97%), low limits of detection (0.2-1.1 µg L-1), and good repeatability (relative standard deviation values 4-10%) were achieved. The proposed method was successfully applied for the extraction of the target analytes from different kinds of water samples (river, lake, and swimming pool). The usage of a chitosan membrane in the extraction process presents many advantages, as it is a biodegradable and versatile support, offering a good alternative to commercial plastic materials commonly used in this methodology and these procedures.

8.
Electrophoresis ; 32(16): 2107-13, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23479790

RESUMEN

The presence of pharmaceuticals in the environment due to growing worldwide consumption has become an important problem that requires analytical solutions. This paper describes a CE determination for several nonsteroidal anti-inflammatory drugs (ibuprofen, naproxen, ketoprofen, diclofenac, ketorolac, aceclofenac and salicylic acid) in environmental waters using hollow fiber membrane liquid-phase microextraction. The extraction was carried out using a polypropylene membrane supporting dihexyl ether and the electrophoretic separation was performed in acetate buffer (30 mM, pH 4) using ACN as the organic modifier. Detection limits between 0.25 and 0.86 ng/mL were obtained, respectively. The method could be applied to the direct determination of the seven anti-inflammatories in wastewaters, and five of them have been determined or detected in different urban wastewaters.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Electroforesis Capilar/métodos , Microextracción en Fase Líquida/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Modelos Lineales , Microextracción en Fase Líquida/instrumentación
9.
J Pharm Biomed Anal ; 202: 114163, 2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34052552

RESUMEN

A solvent-modified micellar electrokinetic chromatography method was developed following the Quality by Design approach for the simultaneous determination of sitagliptin (SIT), an oral antihyperglycemic drug, and its main impurities derived from the synthesis process. The separation system was identified in the scouting phase and was made by sodium dodecyl sulphate (SDS) micelles with the addition of n-butanol and methanol. The knowledge space was investigated through an asymmetric screening matrix, taking into consideration eight critical method parameters (CMPs) involving the composition of the background electrolyte in terms of buffer concentration and pH, the concentration of surfactants and organic modifiers, and voltage. The critical method attributes (CMAs) were identified as analysis time and the distance between the tail of the electroosmotic flow system peak and the front edge of impurity I1 (sitagliptin triazole hydrochloride). A Box-Behnken Design was used in response surface methodology for calculating the quadratic models relating the CMPs to the CMAs. From the models it was possible to compute the method operable design region (MODR) through Monte-Carlo simulations. The MODR was identified in the probability maps as the multidimensional zone where the risk of failure to achieve the desired values for the CMAs was lower than 10 %. The experimental conditions corresponding to the working point, with the MODR interval, were the following: background electrolyte, 14 (10-18) mM borate buffer pH 9.20, 100 mM SDS, 13.6 (11.1-16.0) %v/v n-butanol, 6.7 (4.5-8.8) %v/v methanol; voltage and temperature were set to 28 kV and 22 °C, respectively. The developed CE method was validated in accordance with International Council for Harmonisation guidelines and was applied to the analysis of SIT tablets. The routine analysis for the quality control of the pharmaceutical product could be conducted in about 11 min.


Asunto(s)
Cromatografía Capilar Electrocinética Micelar , Micelas , Reproducibilidad de los Resultados , Fosfato de Sitagliptina , Dodecil Sulfato de Sodio , Solventes
10.
Anal Chim Acta ; 1179: 338832, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34535259

RESUMEN

A selective electromembrane extraction procedure for the extraction of Enrofloxacin, Marbofloxacin and Flumequine, usually employed as antibiotic in veterinarian use, is proposed by using a chitosan biofilm, composed by 60% (w/w) chitosan and 40% (w/w) Aliquat®336, as active biopolymeric support. The interaction mechanism occurring between the target drugs and the biopolymer has been deeply studied using the Quantum Theory of Atoms in Molecules. The obtained results show the interaction between the extracted fluoroquinolones and the biomembrane is stabilized by two hydrogen bonds formed between both the carboxyl and keto groups of the drugs with both the amine and hydroxyl groups of glucosamine in the biopolymer. The energetic results agree with the high extraction efficiency obtained for Marbofloxacin, Enrofloxacin and Flumequine in terms of enrichment factors (83, 82 and 58, respectively) in presence of other fluoroquinolones. Under optimum conditions, the proposed electromembrane extraction method exhibits wide linear ranges of 4.2-200 µg L-1, 5.6-200 µg L-1 and 5.1-200 µg L-1, respectively; low limits of detection close to 1.3 µg L-1 and appropriate repeatability (relative standard deviation values 4-7%).


Asunto(s)
Quitosano , Biopelículas , Cromatografía Líquida de Alta Presión , Enrofloxacina , Fluoroquinolonas
11.
Sci Rep ; 10(1): 7615, 2020 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-32376856

RESUMEN

The use of first and second generation antiepileptic drugs during pregnancy doubles the risk of major congenital malformations and other teratogenic defects. Lacosamide (LCM) is a third-generation antiepileptic drug that interacts with collapsing response mediator protein 2, a protein that has been associated with neurodevelopmental diseases like schizophrenia. The aim of this study was to test the potential teratogenic effects of LCM on developing embryos and its effects on behavioural/histological alterations in adult mice. We administered LCM to pregnant mice, assessing its presence, and that of related compounds, in the mothers' serum and in embryonic tissues using liquid chromatography coupled to quadrupole/time of flight mass spectrometry detection. Embryo morphology was evaluated, and immunohistochemistry was performed on adult offspring. Behavioural studies were carried out during the first two postnatal weeks and on adult mice. We found a high incidence of embryonic lethality and malformations in mice exposed to LCM during embryonic development. Neonatal mice born to dams treated with LCM during gestation displayed clear psychomotor delay and behavioural and morphological alterations in the prefrontal cortex, hippocampus and amygdala that were associated with behaviours associated with schizophrenia spectrum disorders in adulthood. We conclude that LCM and its metabolites may have teratogenic effects on the developing embryos, reflected in embryonic lethality and malformations, as well as behavioural and histological alterations in adult mice that resemble those presented by patients with schizophrenia.


Asunto(s)
Feto/anomalías , Feto/efectos de los fármacos , Lacosamida/efectos adversos , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Esquizofrenia/fisiopatología , Afecto/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Femenino , Incidencia , Locomoción/efectos de los fármacos , Memoria/efectos de los fármacos , Ratones , Embarazo
12.
Food Chem ; 287: 115-125, 2019 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-30857680

RESUMEN

A practice in wine vinegar production is the addition of grape-must caramel to correct and unify the final colour of different batches. Although current legislation allows it, the effect in vinegars' quality has not been studied yet and it can become a fraud when it is used to simulate the effect of a longer ageing. Therefore, the aim of this work was to assess multidimensional fluorescence as a cost-effective and fast technique for detecting and quantifying grape-must caramel in vinegars. Different amounts of grape-must caramel and multivariate data analysis, as Parallel Factor Analysis (PARAFAC), N-way partial least squares and partial least squares discrimination and regression (NPLS-DA, PLS-DA and NPLS) were studied. Triangle sensory test was also performed. Results demonstrated the ability of this methodology in the detection and quantification of grape-must caramel (low prediction errors, RMSEP ≈ 0.24) and the effects that grape-must caramel has upon a PDO vinegar's final quality.


Asunto(s)
Ácido Acético/análisis , Extractos Vegetales/química , Espectrometría de Fluorescencia/métodos , Vitis/química , Vino/análisis
13.
J Chromatogr A ; 1568: 205-213, 2018 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-30005942

RESUMEN

A capillary electrophoresis method for the simultaneous determination of the enantiomeric purity and of impurities of the chiral calcimimetic drug cinacalcet hydrochloride has been developed following Quality by Design principles. The scouting phase was aimed to select the separation operative mode and to identify a suitable chiral selector. Among the tested cyclodextrins, (2-carboxyethyl)-ß-cyclodextrin and (2-hydroxypropyl)-γ-cyclodextrin (HPγCyD) showed good chiral resolving capabilities. The selected separation system was solvent-modified capillary zone electrophoresis with the addition of HPγCyD and methanol. Voltage, buffer pH, methanol concentration and HPγCyD concentration were investigated as critical method parameters by a multivariate strategy. Critical method attributes were represented by enantioresolution and analysis time. A Box-Behnken Design allowed the contour plots to be drawn and quadratic and interaction effects to be highlighted. The Method Operable Design Region (MODR) was identified by applying Monte-Carlo simulations and corresponded to the multidimensional zone where both the critical method attributes fulfilled the requirements with a desired probability π≥90%. The working conditions, with the MODR limits, corresponded to the following: capillary length, 48.5cm; temperature, 18°C; voltage, 26kV (26-27kV); background electrolyte, 150mM phosphate buffer pH 2.70 (2.60-2.80), 3.1mM (3.0-3.5mM) HPγCyD; 2.00% (0.00-8.40%) v/v methanol. Robustness testing was carried out by a Plackett-Burman matrix and finally a method control strategy was defined. The complete separation of the analytes was obtained in about 10min. The method was validated following the International Council for Harmonisation guidelines and was applied for the analysis of a real sample of cinacalcet hydrochloride tablets.


Asunto(s)
Cinacalcet/química , Cinacalcet/aislamiento & purificación , Electroforesis Capilar/métodos , Contaminación de Medicamentos , Concentración de Iones de Hidrógeno , Método de Montecarlo , Probabilidad , Medición de Riesgo , Solventes , Estereoisomerismo , beta-Ciclodextrinas/química , gamma-Ciclodextrinas/química
14.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1044-1045: 63-69, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28086202

RESUMEN

An easy and environmental friendly method, based on the use of magnetic molecular imprinted polymers (mag-MIPs) is proposed for the simultaneous extraction of the 16 U.S. EPA polycyclic aromatic hydrocarbons (PAHs) priority pollutants. The mag-MIPs based extraction protocol is simple, more sensitive and low organic solvent consuming compared to official methods and also adequate for those PAHs more retained in the particulate matter. The new proposed extraction method followed by HPLC determination has been validated and applied to different types of water samples: tap water, river water, lake water and mineral water.


Asunto(s)
Tecnología Química Verde/métodos , Imanes/química , Impresión Molecular/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Límite de Detección , Modelos Lineales , Hidrocarburos Policíclicos Aromáticos/química , Reproducibilidad de los Resultados , Contaminantes Químicos del Agua/química , Calidad del Agua
15.
Anal Chim Acta ; 858: 1-15, 2015 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-25597796

RESUMEN

Parabens are a family of synthetic esters of p-hydroxibenzoic acid widely used as preservatives in cosmetics and health-care products, among other daily-use commodities. Recently, their potential endocrine disrupting effects have raised concerns about their safety and their potential effects as emerging pollutants, leading to the regulation of the presence of parabens in commercial products by national and trans-national organizations. Also, this has led to an interest in developing sensible and reliable methods for their determination in environmental samples, cosmetics and health-care products. This paper is a comprehensive up-to-date review of the literature concerning the determination of parabens in environmental samples and cosmetic and health-care products. A brief revision of the literature concerning the traditional determination of parabens (1980-2003) is included, followed by an in-depth revision of the recent developments in both measurement and extraction methods for parabens in the last years (2003-2013). Finally, possible future perspectives in this field are proposed.


Asunto(s)
Técnicas de Química Analítica/métodos , Cosméticos/química , Parabenos/análisis , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Técnicas de Química Analítica/tendencias , Cromatografía Líquida de Alta Presión/métodos , Electroforesis/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Extracción en Fase Sólida/métodos
16.
Talanta ; 122: 214-22, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24720986

RESUMEN

The toxicological effects of diverse pollutants typically found on wastewaters of diverse origin (industrial, urban, etc.) have led to regulation of their emission by national and trans-national organizations, and an increasing interest in the development of fast and reliable methods for their analysis. This paper is an up-to-date comprehensive review on the analytical applications of chemiluminescence technique (characterized by high sensitivity, wide dynamic ranges and simple instrumentation) to the analysis of wastewaters, emphasizing the different kinds of pollutants that have been studied with these methods and discussing the different approaches followed by the authors as CL reactions, devices and coupled methods.


Asunto(s)
Técnicas Electroquímicas/métodos , Mediciones Luminiscentes/métodos , Aguas Residuales/análisis , Aguas Residuales/química
17.
Sci Total Environ ; 443: 1-6, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23178884

RESUMEN

This work proposes for the first time the use of a three phase hollow fiber liquid phase microextraction (HF-LPME) procedure for the extraction, and the later HPLC determination using fluorescence detection, of two much known endocrine disrupting compounds (EDCs): n-octylphenol (OP) and n-nonylphenol (NP). The extraction was carried out through a dihexyl ether liquid membrane supported on an Accurel® Q3/2 polypropylene hollow fiber. Optimum pH for donor and acceptor phases and extraction time were established. Enrichment (preconcentration) factors of 50 were obtained that allows detection limits of 0.54 and 0.52 ng mL(-1) for OP and NP, respectively. The method was successfully applied to the determination of these EDCs in environmental water samples, including urban wastewaters.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Disruptores Endocrinos/análisis , Microextracción en Fase Líquida/métodos , Fenoles/análisis , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Límite de Detección , Reproducibilidad de los Resultados
18.
Talanta ; 99: 55-61, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22967521

RESUMEN

This work proposes for the first time the use of a three phase hollow fiber liquid phase microextraction (HF-LPME) procedure for the simultaneous extraction, and the later HPLC determination, of some phenol substituting compounds (alkyl-, chloro- and nitrophenols) that are considered as highly toxic compounds and/or endocrine disrupting ones. The substances studied include four chlorophenols (CPs): 2,4-dichlorophenol (2,4-DCP), 2,5-dichlorophenol (2,5-DCP), 2,6-dichlorophenol (2,6-DCP) and pentachlorophenol (PCP), three nitrophenols (NPs): 2,4-dinitrophenol (2,4-DNP), 2,5-dinitrophenol (2,5-DNP) and 2,6-dinitriphenol (2,6-DNP) and two alkylphenols (APs): tert butylphenol (TBP) and sec butylphenol (SBP). The extraction was carried out through a dihexyl ether liquid membrane supported on an Accurel(®) Q3/2 polypropylene hollow fiber. Optimum pH for donor and acceptor phases and extraction time were established. The enrichment (preconcentration) factors obtained were between 30 and 700 that allows detection limits between 140 and 290 pg mL(-1). The method was successfully applied to the determination of the compounds in environmental water samples, including urban wastewaters.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Microextracción en Fase Líquida/métodos , Fenol/análisis , Fenol/aislamiento & purificación , Clorofenoles/análisis , Clorofenoles/aislamiento & purificación , Concentración de Iones de Hidrógeno , Modelos Lineales , Membranas Artificiales , Nitrofenoles/análisis , Nitrofenoles/aislamiento & purificación , Fenol/química , Solventes/química , Factores de Tiempo , Aguas Residuales/química , Agua/química
19.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(2): 197-204, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21185241

RESUMEN

In this paper, three phase-hollow fiber-based liquid phase microextraction (HF-LPME) combined with a HPLC procedure using diode array (DAD) and fluorescence detection (FLD) has been developed for the determination of four widely used sulfonamides: sulfadiazine, sulfamerazine, sulfamethazine, sulfamethoxazole and their main metabolites, the corresponding N(4)-acetyl derivatives: N(4)-acetyl-sulfadiazine, N(4)-acetyl-sulfamerazine, N(4)-acetyl-sulfamethazine, N(4)-acetyl-sulfamethoxazole. A Q3/2 Accurel KM polypropylene hollow fiber supporting 1-octanol was used between a 2 M Na(2)SO(4) aqueous solution (pH 4) as a donor phase and aqueous solution (pH 12) as an acceptor phase. The procedure allows very low detection and quantitation limits of 0.3-33 ng L(-1) and 0.9-100 ng L(-1), respectively. The proposed method was applied to the determination of the analytes in environmental water samples (surface, tap and wastewater).


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía Líquida de Alta Presión/métodos , Sulfonamidas/análisis , Contaminantes Químicos del Agua/análisis , Análisis de los Mínimos Cuadrados , Reproducibilidad de los Resultados , Ríos/química , Sulfonamidas/química , Contaminantes Químicos del Agua/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA