Temperature‐controlled ionic liquid‐dispersive liquid‐phase microextraction for preconcentration of chlorotoluron, diethofencarb and chlorbenzuron in water samples
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This article describes a new, rapid and sensitive method for the determination of chlorotoluron, diethofencarb and chlorbenzuron from water samples with temperature‐controlled ionic liquid‐dispersive liquid‐phase microextraction. In the preconcentration procedure, ionic liquid 1‐hexyl‐3‐methylimidazolium hexafluorophosphate [C 6 MIM] [PF 6] was employed as the extraction solvent. The parameters, such as volume of [C 6 MIM] [PF 6], sample pH, extraction time, centrifuging time, temperature and salting‐out effect, were investigated in detail. Under the optimal extraction conditions, it has been found that three analytes had excellent LODs (S/N=3) in the range of 0.04–0.43 μg/L. The RSDs (n=6) were in the range of 1.3–4.7%. The proposed method was evaluated with lake water, tap water and melted snow water samples. The experimental results indicated that the proposed method had excellent prospect and would be widely used in the future.
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In four IL-DLLME pesticide works, no disperser solvent was used (only the IL [HMIm][PF6]), because dispersion is temperature-assisted.
“We should mention that, in four of these works [13-16], no disperser solvent was used (only the IL [HMIm][PF6]), since the dispersion is temperature-assisted.”
From Dispersive liquid-liquid microextraction for determination of organic analytes (2010) · cites this paper as [15]
For IL-DLLME of pesticides, a relatively small number of works has been published, especially in recent years.
“Regarding IL-DLLME of pesticides, a relatively small number of works has come out, especially in recent years [13-16,32,38,47,50].”
From Dispersive liquid-liquid microextraction for determination of organic analytes (2010) · cites this paper as [15]
The temperature-controlled LPME variation has been applied using only ionic liquids as extractants.
“This variation of the technique has been applied using only ionic liquids (ILs) as extractants [13-16]”
From Dispersive liquid-liquid microextraction for determination of organic analytes (2010) · cites this paper as [15]
In most IL-DLLME pesticide works, water samples were analyzed using HPLC as the separation technique.
“In most cases, water samples have also been analyzed using HPLC as the separation technique [13-16,32,47].”
From Dispersive liquid-liquid microextraction for determination of organic analytes (2010) · cites this paper as [15]
IL-DLLME has a drawback of a wide peak at the beginning of the chromatogram corresponding to the IL.
“As can be seen, at the beginning of the chromatogram, there appeared a wide peak, corresponding to the IL - one of the main drawbacks of using IL-DLLME, as already reported [14-19,32,38,47,50,65-67] -although, in this case, it did not interfere at all in the separation.”
From Dispersive liquid-liquid microextraction for determination of organic analytes (2010) · cites this paper as [15]
The Introduction discusses drawbacks of ionic liquids, but names cost and difficulty of synthesis, not a chromatographic peak. The Instrument section describes the HPLC setup without reporting a wide peak at the start of a chromatogram. Searches for an IL peak, chromatograms, and interference found no passage addressing the claimed drawback. (LLM, conf=0.73)
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- Authors
- Zhou, Q., Zhang, X., Xie, G., & Xiao, J.
- Affiliations
- Henan Normal University (CN)
- Henan Institute of Science and Technology (CN)
- University of Science and Technology Beijing (CN)
- Corresponding author
- Zhou, Qingxiang
- Venue
- Journal of Separation Science
- Publisher
- Wiley
- Published
- 2009-11
- Volume
- 32
- Issue
- 22
- Pages
- 3945-3950
- ISSN
- 1615-9306 (ISSN-L)
- 1615-9314
- OpenAlex
- W1977410162
- Cited by
- 33
- References
- 34
- Citations by year
- 2023: 1 · 2022: 1 · 2020: 2 · 2019: 2 · 2018: 1 · 2017: 1 · 2016: 1 · 2015: 3 · 2014: 3 · 2013: 2 · 2012: 7
- FWCI
- 5.12
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Journal of Separation Science (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Natural Science Foundation of China (020877022)
- High-Tech Research & Development Planning (2006AA06Z424)
- Personal Innovation Foundation of Universities in Henan Province
- Natural Science Foundation of Henan Province (092300410126)
- Fund of Henan Normal University (2006PL06)
- Henan Key Laboratory for environmental pollution control
- Topics
- Physical Sciences › Chemistry › Analytical Chemistry › Analytical chemistry methods development
- Life Sciences › Agricultural and Biological Sciences › Food Science › Pesticide Residue Analysis and Safety
- Physical Sciences › Chemical Engineering › Catalysis › Ionic liquids properties and applications
- Keywords
- ionic liquids, chlortoluron, diethofencarb, water samples, 1-hexyl-3-methylimidazolium hexafluorophosphate, salting-out, lake water, tap water, snowmelt water
- MeSH terms
- Chlorobenzenes, Hydrogen-Ion Concentration, Imides, Ions, Phenylurea Compounds, Temperature, Water Pollutants, Chemical, Phenylcarbamates, Limit of Detection
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