کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5134988 | 1493414 | 2017 | 8 صفحه PDF | دانلود رایگان |
- Evaporation-assisted dispersive liquid-liquid microextraction procedure (EVA-DLLME).
- EVA-DLLME coupled with high performance liquid chromatography tandem-mass spectrometry (HPLC-MC/MC).
- Simultaneous pretreatment of a large number of samples.
- HPLC-MC/MC determination of insecticides in wine using new EVA-DLLME.
A sample pre-treatment technique based on evaporation-assisted dispersive liquid-liquid microextraction (EVA-DLLME), followed by HPLC-MS/MS has been developed for the determination of organophosphate insecticides (malathion, diazinon, phosalone) in wine samples. The procedure includes the addition of mixture of organic solvents (with density higher than water), consisting of the extraction (low density) and volatile (high density) solvents, to aqueous sample followed by heating of the mixture obtained, what promotes the volatile solvent evaporation and moving extraction solvent droplets from down to top of the aqueous sample and, as a consequence, microextraction of target analytes. To initiate the evaporation process an initiator is required. It was established that hexanol (extraction solvent) and dichloromethane (volatile solvent) mixture (1:1, v/v) provides effective microextraction of the insecticides from wine samples with recovery from 92 to 103%. The conditions of insecticides' microextraction such as selection of extraction solvent, ratio of hexanol/dichloromethane and hexanol/sample, type and concentration of initiator, and effect of ethanol as one of the main components of wine have been studied. Under optimal experimental conditions the linear detection ranges were found to be 10â7-10â3 g Lâ1 for malathion, 10â9-10â4 g Lâ1 for diazinon, and 10â6-10â2 g Lâ1 for phosalone. The LODs, calculated from a blank test, based on 3Ï, found to be 3 Ã 10â8 g Lâ1 for malathion, 3 Ã 10â10 g Lâ1 for diazinon and 3 Ã 10â7 g Lâ1 for phosalone. The advantages of EVA-DLLME are the rapidity, simplicity, high sample throughput and low cost. As an outcome, the analytical results agreed fairly well with the results obtained by a reference GC-MS method.
Journal: Journal of Chromatography A - Volume 1512, 25 August 2017, Pages 107-114