Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Anal Bioanal Chem ; 375(3): 389-99, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12589504

RESUMO

Pressurised hot water extraction (PHWE) was coupled on-line with microporous membrane liquid-liquid extraction (MMLLE) and gas chromatography (GC) in the analysis of polycyclic aromatic hydrocarbon (PAH) compounds in soil. The MMLLE serves as a trapping device after the PHWE. Water from PHWE is directed to the donor side of the membrane unit and the analytes are extracted to the acceptor solution on the other side of the membrane. The role of MMLLE is to clean and concentrate the extract, which is then transferred on-line to the GC via a sample loop and an on-column interface using partially concurrent solvent evaporation. Separate optimisation of MMLLE and simulations of the PHWE-MMLLE connection were carried out before the actual on-line coupling. After optimisation of the whole on-line system, the efficiencies of the PHWE-MMLLE-GC and PHWE-solid-phase trap extractions were compared. The PHWE-MMLLE-GC method allowed on-line analysis of soil samples. The method was linear, with limits of detection in the range 0.05-0.13 ng and limits of quantification 0.65-1.66 microg g(-1). Comparison of the results with those obtained by other techniques confirmed the good performance.


Assuntos
Fracionamento Químico/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Fracionamento Químico/instrumentação , Cromatografia Gasosa , Desenho de Equipamento , Sistemas On-Line , Sensibilidade e Especificidade , Solo/normas
2.
Anal Bioanal Chem ; 372(5-6): 732-6, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11941446

RESUMO

A sample pretreatment method based on microporous membrane liquid-liquid extraction (MMLLE) was developed for the subsequent gas chromatographic determination of pesticides in wine. MMLLE provided efficient and selective extraction with enrichment factors in the range 3-13. The gas chromatographic separation was carried out using on-column injection and flame ionization detection. The method was linear, repeatable and sensitive. The limits of quantification were better than 0.006 mg/L for all the analytes except for iprodione (0.37 mg/L). The method was applied to the determination of pesticides in several red wines of different origin.


Assuntos
Cromatografia Gasosa/métodos , Membranas Artificiais , Resíduos de Praguicidas/análise , Vinho/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA