M. S. Galhiane

Off-line SFE-CZE analysis of carbamates residues in tobacco samples

SummaryDetermination of carbamate residues in tobacco samples was carried out by solid-liquid extraction (SLE) and supercritical-fluid extraction (SFE) methods, both developed for this purpose. The clean-up step was carried out on SPE-Florisil cartridges and the extracts analysed by capillary zone electrophoresis (CZE) with UV detection.The results were compared and SFE using CO2-acetone showed the best results in terms of recovery and generally higher extraction power. SFE in conjunction with CZE proved suitable for carbamate residue analysis in real tobacco samples.

Supercritical fluid extraction of oxadixyl from food crops

SummaryThis work describes the study of a degradation curve of Oxadixyl in field-treated potato and tomato samples. The residues were extracted using classical and supercritical fluid (SFE) extraction methods and analyzed by HRGC/ECD. The extraction techniques were compared and the results indicate the advantages of using SFE as an alternative method for pesticide analyses in these samples.

Extraction of norflurazon residues in cotton seeds with supercritical CO2

SummaryA new method for the extraction of Norflurazon residues in cotton seeds using supercritical CO2 as the extracting fluid is described. The supercritical fluid extraction results were compared with those of the classical procedure using liquid extraction. All SFE experiments were performed using a home-made system. The method presented, besides being faster and more economical than existing methods, showed better recovery, with higher selectivity for Norflurazon extraction.

Supercritical fluid extraction of chlorothalonil residues from apples

SummaryA new method for the extraction of Chlorothalonil residues from apples using supercritical CO2 as the extracting fluid is described. The supercritical fluid extraction results were compared with those obtained by solid-liquid extraction. The results showed that SFE is faster and more selective with better recovery and higher selectivity.

Simultaneous extraction of norflurazon and oxadixyl residues from food crops with supercritical carbon dioxide

SummaryNorflurazon and Oxadixyl residues have been analysed by HRGC-ECD after extraction from field-treated sugar cane and grapes using classical solid-liquid extraction or supercritical fluid extraction. The extraction techniques were compared; the results indicate the advantages of SFE as an alternative method for analysis of pesticides in these samples.

Extraction of Atabron residues from cabbage with supercritical carbon dioxide

SummaryIn this work we present a new procedure for extraction of Atabron residues from cabbage samples using supercritical carbon dioxide. The results obtained with this procedure were compared with those obtained using traditional extraction methods for Atabron residues. The extraction yields found by both procedures are similar but SFE has several advantages, especially higher speed, greater economy, better selectivity and greater reproducibility.

Supercritical fluid extraction of flumetralin in tobacco

SummaryThis work evaluates the level of Flumetralin residues in real tobacco samples. Conventional extraction methods were compared with SFE methods in both static and dynamic modes using CO2 and CO2 with modifier. Additionally, in the dynamic SFE mode, different collection approaches, such as collection at room temperature without solvent, collection at room temperature in the presence of solvent (hexane) and collection in an ice bath, without solvent, were studied. SFE showed itself to be a promising extraction technique for pesticide residues in tobacco samples.

NOVAS APLICAÇÕES DE SISTEMAS DE PARA EXTRAÇÃO COM FLUIDO SUPERCRÍTICO (SFE)" HOME-MADE".: VI. CONTROLE DE AGROTÓXICOS EM PRODUTOS ALIMENTÍCIOS

In the present work, we describe a SFE home-made system used for pesticide residue extraction in food products. The pesticides were extracted using CO2 in the supercritical state as extracting fluid with and without modifiers. The results obtained by SFE have been better than those obtained by conventional extraction method.

GC-ECD evaluation of dicofol toxicity to tropicalAstyanax bimaculatus schubarti

SummaryEvaluation of the toxicity of Dicofol was carried out onAstyanax bimaculatus schubarti, a characteristic fish species living in tropical rivers and lakes. Experiments were under laboratory controlled conditions with atmospheric air flow and dilution water at 25°C in the static mode. Fish samples were collected and submitted to appropriate analytical procedure: Soxhlet extraction, clean-up by Florisil adsorbent and finally quantification by GC-ECD. The results showed good recoveries (> 89%) for the developed method both in water and fish samples. The lethal concentration, LC50, and the bioconcentration factor, BCF, were 18.13 mg L−1 and 241.70, respectively forAstyanax bimaculatus schubarti demonstrating the lipophilic nature of the studied compound.