Ultrasonic nebulization extraction coupled with headspace hollow fiber microextraction of pesticides from root of Panax ginseng C.A. Mey

Applications of Hollow-Fiber and Related Microextraction Techniques for the Determination of Pesticides in Environmental and Food Samples—A Mini Review

Pesticides represent one of the most important groups of analytes in environmental analysis. Moreover, their levels are very frequently determined in food and beverages due to the concern over their possible adverse health effects. Their concentration in samples is usually very low; thus, they have to be preconcentrated. Conventional solvent and solid-phase extractions are mainly used for this purpose, but miniaturized approaches are also being applied more and more often. The present review covers solvent microextractions that use a semi-permeable membrane barrier between the sample and the solvent. The main representatives of this approach are hollow-fiber microextraction (HFME), solvent bar microextraction (SBME), electromembrane extraction (EME), and different variations of those, such as combinations with other sorbent or solvent microextractions, electromigration, etc. The relevant research from the last decade, dealing with the application of these microextractions to the isolation of pesticides from various environmental and food samples, is critically discussed with emphasis on their strengths and weak points.

Headspace Microextraction of Sulfonamides from Honey by Hollow Fibers Coupled with Ultrasonic Nebulization

A new method for the rapid simultaneous determination of five sulfonamides in honey was developed using ultrasonic nebulization-assisted extraction coupled with hollow fiber liquid-liquid-liquid microextraction prior to liquid chromatography. In the present method, the sample solution was nebulized by ultrasonication. Sulfonamides in the aerosol particles were extracted by 1-octanol impregnated in the pores of a hollow fiber and further into the acceptor phase (acid solution, pH 2.0) contained in the lumen of the hollow fiber. Several experimental parameters that affect the extraction efficiency were optimized. The present method provides good recoveries (88.9-114.2%) and acceptable precision (<10.7%), indicating the effective extraction. The detection limits were 4.6-6.8 μg/kg, lower than the maximum residue limits of sulfonamides in honeys. Compared to the traditional extraction methods, the present method requires less organic solvent and operation time, demonstrating excellent cleanup ability and good enrichment efficiency.