Liquid-phase microextraction as a sample preparation technique prior to capillary gas chromatographic-determination of benzodiazepines in biological matrices

Ugland, Hege Grefslie; Krogh, Mette; Rasmussen, Knut

doi:10.1016/s0378-4347(00)00382-0

Cited by 128 publications

(69 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This alcohol has the ability to disrupt hydrophobic and polar interactions between the analyte and the proteins. 12,30,31 However, the addition of methanol interfered with the accuracy of the method, reducing the repeatability of the extraction.…”

Section: Application Of the Methodsmentioning

confidence: 99%

Liquid-phase microextraction for simultaneous chromatographic analysis of three antidepressant drugs in plasma

Eduardo¹,

Maia²,

Freitas³

et al. 2012

Quím. Nova

View full text Add to dashboard Cite

Recebido em 26/1/11; aceito em 20/5/11; publicado na web em 22/7/11 A method using Liquid Phase Microextraction for simultaneous detection of citalopram (CIT), paroxetine (PAR) and fluoxetine (FLU), using venlafaxine as internal standard, in plasma by high performance liquid chromatography with fluorescence detection was developed. The linearity was evaluated between 5.0 and 500 ng mL -1 (r > 0.99) and the limit of quantification was 2.0, 3.0 and 5.0 ng mL -1 for CIT, PAR and FLU, respectively. Therefore, it can be applied to therapeutic drug monitoring, pharmacokinetics or bioavailability studies and its advantages are that it necessary relatively inexpensive equipment and sample preparation techniques.

show abstract

Section: Application Of the Methodsmentioning

confidence: 99%

Liquid-phase microextraction for simultaneous chromatographic analysis of three antidepressant drugs in plasma

Eduardo¹,

Maia²,

Freitas³

et al. 2012

Quím. Nova

View full text Add to dashboard Cite

show abstract

“…20 Os autores obtiveram um fator de enriquecimento de 75 com limite de quantificação de 20 ng mL -1 usando um sistema de três fases (noctanol:ácido clorídrico) e análise por CE-UV. Mais tarde, Ugland et al 50 demonstraram o emprego da técnica para determinação de diazepam e seu principal metabólito (n-desmetildiazepam) em plasma. Neste sistema de duas fases tendo éter diexílico:n-octanol (1:3) como fase orgânica, 1 μL do extrato era diretamente injetado no GC-NPD ("gas chromatography nitrogen phosphorus detection"), dispensando a necessidade de evaporação e reconstituição das amostras antes da injeção.…”

Section: Plasmaunclassified

Microextração em fase líquida (LPME): fundamentos da técnica e aplicações na análise de fármacos em fluidos biológicos

Oliveira¹,

Magalhães²,

Santana³

et al. 2008

Quím. Nova

View full text Add to dashboard Cite

Ribeirão Preto -SP, BrasilRecebido em 1/12/06; aceito em 30/8/07; publicado na web em 26/2/08 LIQUID-PHASE MICROEXTRACTION (LPME): FUNDAMENTALS AND APPLICATIONS TO THE ANALYSIS OF DRUGS IN BIOLOGICAL SAMPLES. The analysis of drugs and metabolites in biological fluids usually requires extraction procedures to achieve sample clean-up and analyte preconcentration. Commonly, extraction procedures are performed using liquid-liquid extraction or solidphase extraction. Nevertheless, these extraction techniques are considered to be time-consuming and require a large amount of organic solvents. On this basis, microextraction techniques have been developed. Among them, liquid-phase microextraction has been standing out. This review describes the liquid-phase microextraction technique based on hollow fibers as a novel and promising alternative in sample preparation prior to chromatographic or electrophoretic analysis. The basic concepts related to this technique and its applicability in extraction of drugs are discussed.Keywords: liquid-phase microextraction; drug analysis; biological samples. INTRODUÇÃOAs técnicas de separação, tais como a cromatografia líquida de alta eficiência (HPLC), a cromatografia gasosa (GC) e a eletroforese capilar (CE), são perfeitamente adequadas para a análise de amostras contendo inúmeros componentes. No entanto, a determinação de analitos presentes em matrizes complexas, tais como plasma, soro, sangue total, homogenatos de tecidos, saliva ou urina, geralmente requer processos prévios de preparação das amostras bem elaborados. 1 Vários motivos justificam estes procedimentos, destacando-se a necessidade de eliminação prévia de parte dos componentes devido à complexidade das matrizes biológicas, a existência de proteínas que podem adsorver nas colunas cromatográficas ou nos capilares, além da necessidade de uma etapa de concentração das substâncias a serem analisadas, geralmente presentes em nível de traços. 1,2 As técnicas mais comumente utilizadas para extração e/ou pré-concentração de compostos presentes em fluidos biológicos são a extração líquido-líquido (LLE) e a extração em fase sólida (SPE). 3 Contudo, as tendências atuais apontam no sentido da utilização de menores quantidades de amostras, até mesmo para análises de traços; obtenção de maior seletividade e especificidade na extração; aumento no potencial para automação ou utilização de métodos "online", reduzindo assim a operação manual; desenvolvimento de métodos menos agressivos ao meio ambiente, com menor desperdí-cio e, o uso de quantidade mínima ou nenhuma de solventes orgâ-nicos. 4,5 Dentro deste contexto, técnicas de microextração que utilizam quantidades mínimas de solventes orgânicos e menos etapas na preparação das amostras vêm sendo desenvolvidas. Entre as principais técnicas de microextração existentes destacam-se a microextração em fase sólida (SPME), a microextração em gota suspensa (SDME) e a extração em membranas ["supported liquid membrane" (SLM), "microporous membrane liquid-liquid extraction" (MMLLE), "liquid-phase mi...

show abstract

“…Following this procedure the acceptor solution could be analyzed by HPLC or capillary electrophoresis (CE), without further treatment. It has been proven that HF-LPME is very useful for extraction of drugs and metabolites from biological matrices and pollutants from environmental samples with simultaneous clean-up of the matrices [25][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

Trace Determination of Tamoxifen in Biological Fluids Using Hollow Fiber Liquid-Phase Microextraction Followed by High-Performance Liquid Chromatography-Ultraviolet Detection

Kashtiaray¹,

Farahani²,

Farhadi³

et al. 2011

AJAC

View full text Add to dashboard Cite

The applicability of hollow fiber liquid-phase microextraction (HF-LPME) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was evaluated for the extraction and determination of tamoxifen (TAM) in biological fluids including human urine and plasma. The drug was extracted from a 15 mL aqueous sample (source phase; SP) into an organic phase impregnated in the pores of the hollow fiber (membrane phase; MP) followed by the back-extraction into a second aqueous solution (receiving phase; RP) located in the lumen of the hollow fiber. The effects of several factors such as the nature of organic solvent, compositions of SP and RP solutions, extraction time, ionic strength and stirring rate on the extraction efficiency were examined and optimized. An enrichment factor of 360 along with substantial sample clean up was obtained under the optimized conditions. The calibration curve showed linearity in the range of 1 -500 ng·mL -1 and the limit of detection was found to be 0.5 ng·mL -1 in aqueous medium. A reasonable relative recovery (≥89%) and satisfactory intra-assay (3.7% -4.2%, n = 3) and inter-assay (7.5% -7.8%, n = 3) precision illustrated good performance of the analytical procedure in spiked human urine and plasma samples.

show abstract

Liquid-phase microextraction as a sample preparation technique prior to capillary gas chromatographic-determination of benzodiazepines in biological matrices

Cited by 128 publications

References 35 publications

Liquid-phase microextraction for simultaneous chromatographic analysis of three antidepressant drugs in plasma

Liquid-phase microextraction for simultaneous chromatographic analysis of three antidepressant drugs in plasma

Microextração em fase líquida (LPME): fundamentos da técnica e aplicações na análise de fármacos em fluidos biológicos

Trace Determination of Tamoxifen in Biological Fluids Using Hollow Fiber Liquid-Phase Microextraction Followed by High-Performance Liquid Chromatography-Ultraviolet Detection

Contact Info

Product

Resources

About