A sensitive and efficient method for the determination of 8 chlorophenoxy acid herbicides in crops by dispersive liquid–liquid microextraction and HPLC with fluorescence detection and identification by MS

Abstract

A simple sample pretreatment method of dispersive liquid–liquid microextraction (DLLME) was developed for fast and efficient extraction of 8 chlorophenoxy acid herbicides.

Hollow-Fiber Liquid-Phase Microextraction (HF-LPME) Coupled On-Line to Liquid Chromatography for the Determination of the Herbicides 2,4-Dichlorophenoxyacetic Acid and 2-Methyl-4-chlorophenoxyacetic Acid and Their Main Metabolites in Soil Samples

“…Microextraction techniques use very small volumes of solvents, as the volume of the extracting phase is small with respect to the volume of the sample, they yield large enrichment factors, and they can be adapted to a wide variety of samples and analytes [15]. Different microextraction techniques have been applied in the determination of acidic compounds from different complex matrices, such as single-drop liquid-phase microextraction (SDLPME) [7,16], dispersive liquid-liquid microextraction (DLLME) [7,17,18], hollow-fiber liquid-phase microextraction (HF-LPME) [7,[19][20][21][22][23], microporous membrane liquid-liquid extraction (MMLLE) [24], and supramolecular solvents (i.e., nanostructured liquids generated from amphiphilic molecules by self-assembly processes) [25]. A combination of membrane-based microextraction with other pretreatment techniques (electromembrane extraction, EME, combined with DLLME [26]) has also been evaluated for the extraction and clean-up of chlorophenols in environmental water samples.…”

In situ voltammetric analysis of 2,4-dichlorophenoxyacetic acid in environmental water using a boron doped diamond electrode and an adapted unmanned air vehicle sampling platform

“…According to the literature the main methods of analysis of 2,4-D are gas chromatography (GC) with mass spectrometry (GC-MS) or flame ionization detector 1,6,7 , high performance liquid chromatography with mass spectrometry (HPLC-MS) or fluorescence detection. 1,8,9 Some electroanalytical determinations of 2,4-D have been reported, almost all, however, has presented a limit of quantification higher than the maxima concentration of 2,4-D allowed by the WHO and USEPA (320 nmol L −1 ) or the CONAMA (140 nmol L −1 ) for drinking water. 1,3,5,10–14 Moreover, some methods employ electrodes based on mercury, which is toxic in itself.…”

A stable mesoporous metal‐organic framework as highly efficient sorbent of dispersive micro solid‐phase extraction for the determination of polycyclic aromatic hydrocarbons by HPLC

“…To resolve these difficulties, the development of reliable sample pretreatment methods for extraction of PAHs with high efficiency is of particular significance. Till now, many sample pretreatment methods have been developed and employed to purify and enrich targets before instrumental analyses, such as LLE , SPE , SPME , and so on. Among various pretreatment methods, dispersive microSPE was demonstrated to be a simple, environment‐friendly, and wide suitable method .…”