Separation and pre‐concentration of glucocorticoids in water samples by ionic liquid supported vortex‐assisted synergic microextraction and HPLC determination

Abstract

We have developed a synergic microextraction procedure based on ionic liquid for the pre-concentration and determination of glucocorticoids in water samples. Using nonionic surfactant Triton X-100 (TX-100) as synergic reagent, 1-butyl-3-methylimidazolium hexa-fluorophosphate accomplished extraction rapidly without heating in water bath. One key property of ionic liquids that highlights their potential is their wide liquid temperature range. The improved extraction was named as ionic liquid supported vortex-assisted synergic microextraction. Compared with the traditional liquid-liquid extraction and cloud point extraction, ionic liquid supported vortex-assisted synergic microextraction was accomplished in 8 min with considerably high recovery. The proposed method greatly improved the sensitivity of HPLC for the determination of glucocorticoids. The results obtained indicated a good linearity with the correlation coefficient of 0.997 over the range of 0.6-300 ng/mL and high sensitivity with LODs of 4.11, 9.19, and 7.50 ng/mL for hydrocortisone butyrate, beclomethasone dipropionate, and nandrolone phenylpropionate, respectively. The RSD of the method was 1.57-1.81% (n = 6) with enrichment factor of 99.85, and good recovery (≥97.24%). The method was successfully applied to the determination of glucocorticoids in mineral water, water of Dianchi lake, and tap water samples.

Iron species determination by task‐specific ionic liquid‐based in situ solvent formation dispersive liquid–liquid microextraction combined with flame atomic absorption spectrometry

“…Also, micro solid‐phase extraction (μ‐SPE) techniques involving IL‐modified surface materials for retention and pre‐concentration of metals have been reported . Temperature‐controlled microextraction (TCME), ultrasound‐assisted DLLME, microwave‐assisted DLLME and vortex‐assisted DLLME are relatively new extraction techniques that combine heating/cooling, ultrasound, microwave or vortex treatments, respectively, with DLLME to accelerate the extraction process. In the DLLME approach, an additional complexing agent is also needed to extract the metal ions into the IL phase and improve its extraction recovery .…”

Rapid pretreatment and determination of bisphenol A in water samples based on vortex-assisted liquid-liquid microextraction followed by high-performance liquid chromatography with fluorescence detection

“…Similar to the DLLME procedure, a high-density solvent, such as chloroform [20,21] and ionic liquid [22], could be exploited as the extraction solvent for pretreatment of pollutants in water samples. Low-density organic solvents were also employed as extraction solvents according to the requirement [23,24].…”

“…Further, vortex‐assisted liquid–liquid microextraction (VALLME) was proposed to avoid using dispersive solvent and obtain lower LOD. Similar to the DLLME procedure, a high‐density solvent, such as chloroform and ionic liquid , could be exploited as the extraction solvent for pretreatment of pollutants in water samples. Low‐density organic solvents were also employed as extraction solvents according to the requirement .…”

Determination of phthalate esters in liquor samples by vortex‐assisted surfactant‐enhanced‐emulsification liquid–liquid microextraction followed by GC–MS

“…After centrifugation, the extractant solvent restores its initial single microdrop shape and is ready for instrumental analysis. VALLME overcomes the main disadvantage of DLLME, and has been successfully applied for the extraction of different compounds since its introduction .…”