Dispersive liquid‐liquid microextraction coupled with pressure‐assisted electrokinetic injection for simultaneous enrichment of seven phenolic compounds in water samples followed by determination using capillary electrophoresis

Abstract

Offline dispersive liquid-liquid microextraction combined with online pressureassisted electrokinetic injection was developed to simultaneously enrich seven phenolic compounds in water samples, followed by determination using capillary electrophoresis, namely phenol, 4-chlorophenol, pentachlorophenol, 2,4,6trichlorophenol, 2,4-dichlorophenol, 2-chlorophenol, and 2,6-dichlorophenol. Several parameters affecting separation performance of capillary electrophoresis and the enrichment efficiency of pressure-assisted electrokinetic injection and dispersive liquid-liquid microextraction were systematically investigated. Under the optimal conditions, seven phenolic compounds were completely separated within 14 min and good enrichment factors were obtained of 61, 236, 3705, 3288, 920, 86, and 1807 for phenol, 4-chlorophenol, pentachlorophenol, 2,4,6-trichlorophenol, 2,4-dichlorophenol, 2-chlorophenol, and 2,6-dichlorophenol, respectively. Good linearity was attained in the range of 0.1-200 μg/L for 2,4-dichlorophenol, 0.5-200 μg/L for 4-chlorophenol, pentachlorophenol, 2,4,6-trichlorophenol, 2-chlorophenol, and 2,6-dichlorophenol, as well as 1-200 μg/L for phenol, with correlation coefficients (r) over 0.9905. The limits of detection and quantification ranging from 0.03-0.28 and 0.07-0.94 μg/L were attained. This two step enrichment method was potentially applicable for the rapid and simultaneous determination of phenolic compounds in water samples. K E Y W O R D Scapillary electrophoresis, dispersive liquid-liquid microextraction, phenolic compounds, pressure-assisted electrokinetic injection, water samples

Determination of phenols in natural and waste waters by capillary electrophoresis after preconcentration on magnetic nanoparticles coated with aminated hypercrosslinked polystyrene

“…The sorption time upon application of the sorbent studied in the present work is shorter compared to Pt fiber coated with single-walled carbon nanotubes (60 min) [11], poly(vinylpyridineethylene dimethacrylate) monolithic material (120 min) [12], polyacrylate fiber (40 min) [13], MIP (120 min [24], 180 min [58]), magnetic nanoparticles (10 min [31], 20 min [32]), as well as than that using pretreatment method (Supporting information Table S13). Upon application of DLLME-PAEKI-CE, characteristics comparable with the present work were achieved (LOD = 0.03-0.28 μg/L, extraction time = 14 min) [21]; however, MSPE-CE allows one to perform detection in a wider range (0.2-950 μg/L).…”

“…DLLME combined with pressure-assisted electrokinetic injection (PAEKI) was developed by Suya Ma et al for simultaneous determination of PL, 4-CP, 2-CP, 2,4,6-trichlorophenol (TCP), and 2,4-DCP. The EF reached values of 61-3288 [21].…”

“…Trace amounts of PLs in aqueous media are usually determined by HPLC [10][11][12], GC [13,14], LC [15][16][17], microemulsion electrokinetic chromatography [18], CE [19][20][21], and spectrophotometry (SP) [22]. Typically, the direct determination of an analyte is preceded by sample preparation, which is often performed using LLE [15], LPME [23], SBSE [12], dispersive liquid-liquid microextraction (DLLME) [15,18,20,22], SPE [10,14,19,24], and SPME [11,13].…”

A simple and efficient sequential electrokinetic and hydrodynamic injections in micellar electrokinetic chromatography method for quantification of anticancer drug 5‐fluorouracil and its metabolite in human plasma

“…However, when the voltage was too high, the peak shape began to deteriorate, and peak area and peak height began to decrease. This was probably due to the excessive electropercolation pushing the analytes out of the capillary orifice, making the accumulation effect worse (Ma et al, 2019). In addition, it was also observed that, when the voltage was high (>−7 kV), the separation was prone to flow instability and poor repeatability of the targeted analytes.…”

Novel hydrophobic deep eutectic solvent for vortex-assisted liquid phase microextraction of common acaricides in fruit juice followed by HPLC-UV determination

“…Different organic, ionic, and deep eutectic solvents (DESs) have been used in liquid phase extraction and microextraction procedures as the extractive media. [12][13][14][15][16][17][18][19][20][21] In the recent years DESs have attracted many attentions due to their expensiveness, easy preparation, high extraction capability, and less toxicity. DES is a homogeneous and clear solution formed by combining hydrogen bond donor (HBD) with hydrogen bond acceptor (HBA) in a certain ratio at the suitable temperature.…”