Solid-based disperser liquid-liquid microextraction for the preconcentration of phthalate esters and di-(2-ethylhexyl) adipate followed by gas chromatography with flame ionization detection or mass spectrometry

Abstract

A new approach for the development of a dispersive liquid-liquid microextraction followed by GC with flame ionization detection was proposed for the determination of phthalate esters and di-(2-ethylhexyl) adipate in aqueous samples. In the proposed method, solid and liquid phases were used as the disperser and extractant, respectively, providing a simple and fast mode for the extraction of the analytes into a small volume of an organic solvent. In this method, microliter levels of an extraction solvent was added onto a sugar cube and it was transferred into the aqueous phase containing the analytes. By manual shaking, the sugar was dissolved and the extractant was released into the aqueous phase as very tiny droplets to provide a cloudy solution. Under optimized conditions, the proposed method showed good precision (RSD less than 5.2%), high enrichment factors (266-556), and low LODs (0.09-0.25 μg/L). The method was successfully applied for the determination of the target analytes in different samples, and good recoveries (71-103%) were achieved for the spiked samples. No need for a disperser solvent and higher enrichment factors compared with conventional dispersive liquid-liquid microextraction and low cost and short sample preparation time are other advantages of the method.

Cyclodextrin‐assisted dispersive liquid–liquid microextraction for the preconcentration of carbamazepine and clobazam with subsequent sweeping micellar electrokinetic chromatography

“…The effect of the NaCl concentration of 0–10% was investigated. The results show that the peak areas of the two analytes decreased when the NaCl concentration increased from 0 to 10% w/w, which can be attributed to the increase in solution viscosity and restraint of the mass transfer of analytes into the organic solvent . Therefore, salt was not used in the following experiments.…”

“…USAEME has been used to extract carbamazepine for the GC analysis. In the solid‐based DLLME (SB‐DLLME), the dispersive solvent is replaced by a sugar cube as a solid disperser . An extraction solvent is added onto a sugar cube and transferred into the analyte solution.…”

Deep eutectic solvent based gas-assisted dispersive liquid-phase microextraction combined with gas chromatography and flame ionization detection for the determination of some pesticide residues in fruit and vegetable samples

“…Therefore, application of microextraction methods such as SPME , single‐drop microextraction , hollow‐fiber LPME , and dispersive liquid–liquid microextraction (DLLME) in determination of pesticides is more common. However, these methods have some disadvantages such as (a) the use of relatively expensive and fragile fibers, and also occurrence of sample carryover in SPME; (b) organic drop instability and possibility of air bubble formation in single‐drop microextraction; (c) requirement of long extraction time in hollow‐fiber LPME; and (d) the use of relatively high volume of a disperser solvent in conventional DLLME methods, which leads to reduced extraction efficiency, and the use of hazardous solvents such as halogenated hydrocarbons in the vast majority of them . Compared to the other microextraction methods mentioned above, DLLME results in significantly reduced extraction times is simpler and in most cases offers higher extraction efficiencies .…”

Preparation and application of a coated-fiber needle extraction device

“…In recent years, many different techniques have been developed and successfully used to extract and detect VOCs, such as SPME techniques [4][5][6][7], sorbent traps [8][9][10], needletrap extraction (NTE) technology [11][12][13][14][15], and so on. In this field, NTE technology, which is a simple and cost-effective extraction process using solvent-free extraction and thermal desorption for the determination of VOCs, was recently developed [16].…”