Comparison of three different dispersive liquid–liquid microextraction modes performed on their most usual configurations for the extraction of phenolic, neutral aromatic, and amino compounds from waters

Abstract

In this work we seek clues to select the appropriate dispersive liquid-liquid microextraction mode for extracting three categories of compounds. For this purpose, three common dispersive liquid-liquid microextraction modes were compared under optimized conditions. Traditional dispersive liquid-liquid microextraction, in situ ionic liquid dispersive liquid-liquid microextraction, and conventional ionic liquid dispersive liquid-liquid microextraction using chloroform, 1-butyl-3-methylimidazolium tetrafluoroborate, and 1-hexyl-3-methylimidazolium hexafluorophosphate as the extraction solvent, respectively, were considered in this work. Phenolic, neutral aromatic, and amino compounds (each category included six members) were studied as analytes. The analytes in the extracts were determined by high-performance liquid chromatography with UV detection. For the analytes with polar functionalities, the in situ ionic liquid dispersive liquid-liquid microextraction mode mostly led to better results. In contrast, for neutral hydrocarbons without polar functionalities, traditional dispersive liquid-liquid microextraction using chloroform produced better results. In this case, where dispersion forces were the dominant interactions in the extraction, the refractive index of solvent and analyte predicted the extraction performance better than the octanol/water partition coefficient. It was also revealed that none of the methods were successful in extracting hydrophilic analytes (compounds with the log octanol/water partition coefficient <2). The results of this study could be helpful in selecting a dispersive liquid-liquid microextraction mode for the extraction of various groups of compounds.

Determination of Selected Pyrrolizidine Alkaloids in Honey by Dispersive Liquid–Liquid Microextraction and Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry

“…Initially, the influence of pH on DLLME efficiency was investigated, because pH might strongly affect the LLE efficiency of ionizable compounds, such as PAs. − ,, Four pH values (2, 7, 9.6, and 11.2) were investigated using 1000 μL of CHCl 3 /MeCN 4/6 v/v as an extractant/disperser mixture. At pH 2, no analyte was recovered by DLLME.…”

A review: Exploratory analysis of recent advancement in green analytical chemistry application

“…Analytes with polar groups give the best results with in-situ ionic liquid dispersiveliquid-liquid micro-extraction, whereas neutral hydrocarbon compounds with polar groups use chloroform solvent called traditional dispersive liquid-liquid microextraction techniques. Hydrophilic analytes were not suitable to be extracted by any of the liquidliquid micro-extraction [77]. Liquid phase microextraction is of three types.…”

Recent advances of green pretreatment techniques for quality control of natural products

“…DLLME is suitable for analysis of analytes with high or medium lipophilic properties, but not for analysis of neutral analytes with strong hydrophilicity. Saraji et al compared three different DLLME modes for extracting several compounds from water, including traditional DLLME, in situ ionic liquid DLLME, and conventional ionic liquid DLLME [67]. As the results showed, the in situ ionic liquid DLLME could obtain better results mostly for polarity analytes.…”