Ultrapreconcentration and determination of organophosphorus pesticides in water by solid‐phase extraction combined with dispersive liquid–liquid microextraction and high‐performance liquid chromatography

Solid‐phase extraction coupled with dispersive liquid–liquid microextraction was developed as an ultra‐preconcentration method for the determination of four organophosphorus pesticides (isocarbophos, parathion‐methyl, triazophos and fenitrothion) in water samples. The analytes considered in this study were rapidly extracted and concentrated from large volumes of aqueous solutions (100 mL) by solid‐phase extraction coupled with dispersive liquid–liquid microextraction and then analyzed using high performance liquid chromatography. Experimental variables including type and volume of elution solvent, volume and flow rate of sample solution, salt concentration, type and volume of extraction solvent and sample solution pH were investigated for the solid‐phase extraction coupled with dispersive liquid–liquid microextraction with these analytes, and the best results were obtained using methanol as eluent and ethylene chloride as extraction solvent. Under the optimal conditions, an exhaustive extraction for four analytes (recoveries >86.9%) and high enrichment factors were attained. The limits of detection were between 0.021 and 0.15 μg/L. The relative standard deviations for 0.5 μg/L of the pesticides in water were in the range of 1.9–6.8% (n = 5). The proposed strategy offered the advantages of simple operation, high enrichment factor and sensitivity and was successfully applied to the determination of four organophosphorus pesticides in water samples.     

Sodium dodecyl sulfate sensitized switchable solvent liquid‐phase microextraction for the preconcentration of protoberberine alkaloids in Rhizoma coptidis

A sodium dodecyl sulfate sensitized switchable solvent liquid‐phase microextraction method was developed and applied to the preconcentration of active alkaloids in Rhizoma coptidis followed by high performance liquid chromatography determination. Before extraction, nonionic triethylamine was converted to its cationic form in the presence of carbon dioxide. Then, the ionic solvent carrying target analytes was once more reverted to its nonionic form by adding sodium hydroxide, as well as phase separation and analytes enrichment were realized simultaneously. Several parameters affecting the approach, such as concentration of sodium dodecyl sulfate, extraction solvent volume, sodium hydroxide concentration, sample phase pH, injection solvent type, and extraction time, were investigated and optimized. The possible microextraction mechanism of double micelle supramolecular inclusion was explored. Under the optimum conditions, the enrichment factors of four protoberberine alkaloids were from 101.8 to 152.0. The linear ranges (with r² ≥ 0.990) were 0.032–4.23, 0.031–4.33, 0.0026–10.04, and 0.0013–4.13 μg/mL for epiberberine, coptisine, palmatine, and berberine, respectively. The detection limits were in the range of 0.16–0.32 ng/mL. Satisfactory accuracies (recoveries 98.8–104.6%) and precisions (RSDs 1.9–10.9%) were also obtained. The results showed that the approach is rapid, effective, eco‐friendly, and easy‐to‐handle for the enrichment and detection of active alkaloids in Rhizoma coptidis.     

Air‐assisted liquid–liquid extraction coupled with dispersive liquid–liquid microextraction and a drying step for extraction and preconcentration of some phthalate esters from edible oils prior to their determination by GC

In this work, a new, cheap, simple, fast, and low organic solvent consuming procedure is proposed for isolation, enrichment, and gas chromatographic determination of some phthalate esters in edible oils. The method is based on a combination of air‐assisted liquid–liquid extraction and dispersive liquid–liquid microextraction followed by a drying step under N₂ gas. Several experimental parameters affecting both extraction and preconcentration steps were investigated and optimized. Under the optimum conditions for the proposed method, wide linear ranges (0.05–800 μg/L) and low detection limits (0.007–0.023 μg/L) were observed. The ranges of enrichment factors and extraction recoveries were 68–340 and 14–68%, respectively. Eventually, the target analytes were successfully determined in different edible oils using the proposed method.     

Ballpoint connector‐protected salt‐oil‐salt liquid phase microextraction for concentration and enrichment of trace anthraquinone compounds in rhubarb

This study proposed a new ballpoint connector‐protected salt‐oil‐salt liquid phase microextraction for extraction and enrichment of trace rhein and chrysophanol in rhubarb prior to determination of the analytes by high performance liquid chromatography. In this study, a handy ballpoint connector (between ballpoint tip and ink chamber) was used as extraction device, in which its cavity was filled with n‐octanol, and the bare n‐octanol in its two opening ends was covered with a thin layer of sodium chloride film. The design subtly assembled salt film onto ballpoint connector for extraction and enrichment, which greatly improved the enrichment factors of the target analytes. Moreover, the novel procedure and its extraction mechanism were described and analyzed, and several crucial parameters reflecting the extraction effect were investigated and optimized. Under optimum conditions, high enrichment factors (247 and 127), good linearities with r ≥ 0.9998, limits of detection (0.6–1.1 ng/mL), relative standard deviations of intra‐ and interday (2.2–8.8% and 4.3–8.9%), and average recoveries (97.6–98.1%), were obtained, respectively. The proposed method can not only eliminate the negative effects from viscosity and ion strength at high salt concentration of sample phase, but also make salting‐out effect be focused on small area so as to maximize the extraction effect.     

Trace determination of five triazole fungicide residues in traditional Chinese medicine samples by dispersive solid‐phase extraction combined with ultrasound‐assisted dispersive liquid–liquid microextraction and UHPLC–MS/MS

A novel and reliable method for determination of five triazole fungicide residues (triadimenol, tebuconazole, diniconazole, flutriafol, and hexaconazol) in traditional Chinese medicine samples was developed using dispersive solid‐phase extraction combined with ultrasound‐assisted dispersive liquid–liquid microextraction before ultra‐high performance liquid chromatography with tandem mass spectrometry. The clean up of the extract was conducted using dispersive solid‐phase extraction by directly adding sorbents into the extraction solution, followed by shaking and centrifugation. After that, a mixture of 400 μL trichloromethane (extraction solvent) and 0.5 mL of the above supernatant was injected rapidly into water for the dispersive liquid–liquid microextraction procedure. The factors affecting the extraction efficiency were optimized. Under the optimum conditions, the calibration curves showed good linearity in the range of 2.0–400 (tebuconazole, diniconazole, and hexaconazole) and 4.0–800 ng/g (triadimenol and flutriafol) with the regression coefficients higher than 0.9958. The limit of detection and limit of quantification for the present method were 0.5–1.1 and 1.8–4.0 ng/g, respectively. The recoveries of the target analytes ranged from 80.2 to 103.2%. The proposed method has been successfully applied to the analysis of five triazole fungicides in traditional Chinese medicine samples, and satisfactory results were obtained.     

Development of a simple and valid method for the trace determination of phthalate esters in human plasma using dispersive liquid–liquid microextraction coupled with gas chromatography–mass spectrometry

A new method was developed for the trace determination of phthalic acid esters in plasma using dispersive liquid–liquid microextraction and gas chromatography with mass spectrometry analysis. Plasma proteins were efficiently precipitated by trichloroacetic acid and then a mixture of chlorobenzene (as extraction solvent) and acetonitrile (as dispersive solvent) rapidly injected to clear supernatant using a syringe. After centrifuging, chlorobenzene sedimented at the bottom of the test tube. 1 μL of this sedimented phase was injected into the gas chromatograph for phthalic acid esters analysis. Different factors affecting the extraction performance, such as the type of extraction and dispersive solvent, their volume, extraction time, and the effects of salt addition were investigated and optimized. Under the optimum conditions, the enrichment factors and extraction recoveries were satisfactory and ranged between 820–1020 and 91–97%, respectively. The linear range was wide (50–1000 ng/mL) and limit of detection was very low (1.5–2.5 ng/mL for all analytes). The relative standard deviations for analysis of 1 μg/mL of the analytes were between 3.2–6.1%. Salt addition showed no significant effect on extraction recovery. Finally, the proposed method was successfully utilized for the extraction and determination of the phthalic acid esters in human plasma samples and satisfactory results were obtained.     

New oil‐in‐salt liquid‐phase microextraction on permutite for the extraction and concentration of alkaloids in Coptis chinensis

A novel oil‐in‐salt liquid‐phase microextraction was developed and introduced for the extraction and concentration of the trace levels of active alkaloids in Coptis chinensis prior to being analyzed by high‐performance liquid chromatography with ultraviolet detection. Also, the oil‐in‐salt extraction mechanism was analyzed, the enrichment factor and extraction recovery were redefined, and the proposed method was compared with other methods. In the approach, the mixed solvent of pentanol/octanol (6:4, v/v) and NaCl (20% w/v) are immobilized on the permutite surface in turn to form oil‐in‐salt double membranes, through which the target analytes can be molecularized though salting‐out effect and be extracted by organic solvent. The main parameters affecting the approach were investigated and optimized. Under the optimized conditions, the enrichment factors of the analytes were 30–117, the linear ranges were 0.002–2 μg/mL for jatrorrhizine, coptisine, and palmatine, and 0.001–3 μg/mL for berberine (r ² ≥ 0.9923). The limits of detection were less than 1 ng/mL. Satisfactory recoveries (84.3%–120.3%) and precision (0.9%–7.5%) were also obtained. These results confirm that the approach is a simple and reliable sample pretreatment procedure and allows for the quantification of active alkaloids in C. chinensis at actual concentration levels.     

Vortex‐assisted surfactant‐enhanced‐emulsification liquid–liquid microextraction of biogenic amines in fermented foods before their simultaneous analysis by high‐performance liquid chromatography

A simple, rapid, sensitive, and environmentally friendly method, based on modified dispersive liquid–liquid microextraction coupled with high‐performance liquid chromatography was developed for the simultaneous determination of five biogenic amines in fermented food samples. Biogenic amines were derivatized with 9‐fluorenylmethyl chloroformate, extracted by vortex‐assisted surfactant‐enhanced emulsification liquid–liquid microextraction, and then analyzed by high‐performance liquid chromatography. Five biogenic amine compounds were separated within 30 min using a C₁₈ column and gradient elution with acetonitrile and 1% acetic acid. Factors influencing the derivatization and extraction efficiency such as type and volume of extraction solvent, type, and concentration of surfactant, pH, salt addition, and vortex time were optimized. Under the optimum conditions, the method provided the enrichment factors in the range of 161–553. Good linearity was obtained from 0.002–0.5 mg/L for cadaverine and tyramine, 0.003–1 mg/L for tryptamine and histamine, and 0.005–1 mg/L for spermidine with coefficient of determination (R²) > 0.992. The limits of detection ranged from 0.0010 to 0.0026 mg/L. The proposed method was successfully applied to analysis of biogenic amines in fermented foods such as fermented fish (plaa‐som), wine and beer where good recoveries were obtained in the range of 83.2–112.5%     

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

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.     

Comparison of three different dispersive liquid–liquid microextraction modes performed on their most usual configurations for the extraction of phenolic,neutral aromatic,and amino compounds from waters

In this work we seek clues to select the appropriate dispersive liquid–liquid microextraction mode for extracting three categories of compounds. For this purpose, three common dispersive liquid–liquid microextraction modes were compared under optimized conditions. Traditional dispersive liquid–liquid microextraction, in situ ionic liquid dispersive liquid–liquid microextraction, and conventional ionic liquid dispersive liquid–liquid microextraction using chloroform, 1‐butyl‐3‐methylimidazolium tetrafluoroborate, and 1‐hexyl‐3‐methylimidazolium hexafluorophosphate as the extraction solvent, respectively, were considered in this work. Phenolic, neutral aromatic, and amino compounds (each category included six members) were studied as analytes. The analytes in the extracts were determined by high‐performance liquid chromatography with UV detection. For the analytes with polar functionalities, the in situ ionic liquid dispersive liquid–liquid microextraction mode mostly led to better results. In contrast, for neutral hydrocarbons without polar functionalities, traditional dispersive liquid–liquid microextraction using chloroform produced better results. In this case, where dispersion forces were the dominant interactions in the extraction, the refractive index of solvent and analyte predicted the extraction performance better than the octanol/water partition coefficient. It was also revealed that none of the methods were successful in extracting hydrophilic analytes (compounds with the log octanol/water partition coefficient <2). The results of this study could be helpful in selecting a dispersive liquid–liquid microextraction mode for the extraction of various groups of compounds.     

Dispersive liquid–liquid microextraction as an effective preanalytical step for the determination of estradiol in human urine

In this work, a fast and effective dispersive liquid–liquid microextraction was developed for the isolation and preconcentration of free 17 β‐estradiol, the main human estrogen, from real human urine samples. To optimize the extraction technique, few important parameters such as type and volume of extraction and dispersive solvents, centrifugation conditions, effect of salt addition, and extraction time were studied. Optimal conditions were obtained when injecting 600 μL mixture of tetrachloromethane as extraction solvent and ethanol as dispersive solvent (1:5, v/v) into 2 mL of urine containing 8% NaCl and following centrifugation at 10 000 rpm, thus reaching enrichment factor 28 and extraction recovery 98% for estradiol. Procedure was evaluated by means of high‐performance liquid chromatography with UV detection (λ = 280 nm) using a C‐18 column and methanol/water (60:40, v/v) as the mobile phase. The method was linear within the concentration range 1.0–250.0 mg/L (r  = 0.9997) and provided a limit of detection of 0.25 mg/L. The proposed method was applied to the determination of free estradiol in real human pregnancy urine.     

Simultaneous derivatization and air‐assisted liquid–liquid microextraction of some parabens in personal care products and their determination by GC with flame ionization detection

A simultaneous derivatization/air‐assisted liquid–liquid microextraction technique has been developed for the sample pretreatment of some parabens in aqueous samples. The analytes were derivatized and extracted simultaneously by a fast reaction/extraction with butylchloroformate (derivatization agent/extraction solvent) from the aqueous samples and then analyzed by GC with flame ionization detection. The effect of catalyst type and volume, derivatization agent/extraction solvent volume, ionic strength of aqueous solution, pH, numbers of extraction, aqueous sample volume, etc. on the method efficiency was investigated. Calibration graphs were linear in the range of 2–5000 μg/L with squared correlation coefficients >0.990. Enhancement factors and enrichment factors ranged from 1535 to 1941 and 268 to 343, respectively. Detection limits were obtained in the range of 0.41–0.62 μg/L. The RSDs for the extraction and determination of 250 μg/L of each paraben were <4.9% (n = 6). In this method, the derivatization agent and extraction solvent were the same and there is no need for a dispersive solvent, which is common in a traditional dispersive liquid–liquid microextraction technique. Furthermore, the sample preparation time is very short.     

Determination of four sulfonylurea herbicides in tea by matrix solid‐phase dispersion cleanup followed by dispersive liquid–liquid microextraction

Matrix solid‐phase dispersion combined with dispersive liquid–liquid microextraction has been developed as a new sample pretreatment method for the determination of four sulfonylurea herbicides (chlorsulfuron, bensulfuron‐methyl, chlorimuron‐ethyl, and pyrazosulfuron) in tea by high‐performance liquid chromatography with diode array detection. The extraction and cleanup by matrix solid‐phase dispersion was carried out by using CN‐silica as dispersant and carbon nanotubes as cleanup sorbent eluted with acidified dichloromethane. The eluent of matrix solid‐phase dispersion was evaporated and redissolved in 0.5 mL methanol, and used as the dispersive solvent of the following dispersive liquid–liquid microextraction procedure for further purification and enrichment of the target analytes before high‐performance liquid chromatography analysis. Under the optimum conditions, the method yielded a linear calibration curve in the concentration range from 5.0 to 10 000 ng/g for target analytes with a correlation coefficients (r²) ranging from 0.9959 to 0.9998. The limits of detection for the analytes were in the range of 1.31–2.81 ng/g. Recoveries of the four sulfonylurea herbicides at two fortification levels were between 72.8 and 110.6% with relative standard deviations lower than 6.95%. The method was successfully applied to the analysis of four sulfonylurea herbicides in several tea samples.     

Sensitive determination of three aconitum alkaloids and their metabolites in human plasma by matrix solid‐phase dispersion with vortex‐assisted dispersive liquid–liquid microextraction and HPLC with diode array detection

A simple and sensitive method for determination of three aconitum alkaloids and their metabolites in human plasma was developed using matrix solid‐phase dispersion combined with vortex‐assisted dispersive liquid–liquid microextraction and high‐performance liquid chromatography with diode array detection. The plasma sample was directly purified by matrix solid‐phase dispersion and the eluate obtained was concentrated and further clarified by vortex‐assisted dispersive liquid–liquid microextraction. Some important parameters affecting the extraction efficiency, such as type and amount of dispersing sorbent, type and volume of elution solvent, type and volume of extraction solvent, salt concentration as well as sample solution pH, were investigated in detail. Under optimal conditions, the proposed method has good repeatability and reproducibility with intraday and interday relative standard deviations lower than 5.44 and 5.75%, respectively. The recoveries of the aconitum alkaloids ranged from 73.81 to 101.82%, and the detection limits were achieved within the range of 1.6–2.1 ng/mL. The proposed method offered the advantages of good applicability, sensitivity, simplicity, and feasibility, which makes it suitable for the determination of trace amounts of aconitum alkaloids in human plasma samples.     

Developing an alcoholic‐assisted dispersive liquid–liquid microextraction for extraction of pentachlorophenol in water

Optimization of alcoholic‐assisted dispersive liquid–liquid microextraction of pentachlorophenol (PCP) and determination of it with high‐performance liquid chromatography (UV‐Vis detection) was investigated. A Plackett‐Burman design and a central composite design were applied to evaluate the alcoholic‐assisted dispersive liquid–liquid microextraction procedure. The effect of seven parameters on extraction efficiency was investigated. The factor studied were type and volume of extraction and dispersive solvents, amount of salt, and agitation time. According to Plackett‐Burman design results, the effective parameters were type and volume of extraction solvent and agitation time. Next, a central composite design was applied to obtain optimal condition. The optimized conditions were obtained at 170‐μL 1‐octanol and 5‐min agitation time. The enrichment factor of PCP was 242 with limits of detection of 0.04 μg L^?1. The linearity was 0.1–100 μg L^?1 and the extraction recovery was 92.7%. RSD for intra and inter day of extraction of PCP were 4.2% and 7.8%, respectively for five measurements. The developed method was successfully applied for the determination of PCP in environmental water samples.     

Determination of organochlorine pesticides in snow water samples by low density solvent based dispersive liquid–liquid microextraction

A simple, rapid, efficient, and environmentally friendly pretreatment based on a low‐density solvent based dispersive liquid–liquid microextraction was developed for determining trace levels of 17 organochlorine pesticides in snow. The parameters affecting the extraction efficiency, such as the type and volume of the extraction and dispersive solvents, extraction time, and salt content, were optimized. The optimized conditions yielded a good performance, with enrichment factors ranging from 271 to 474 and recoveries ranging from 71.4 to 114.5% and relative standard deviations between 1.6 and 14.8%. The detection limits, calculated as three times the signal‐to‐noise ratio, ranged from 0.02 to 0.11 μg/L. The validated method was used to successfully analyze 17 analytes in snow water samples, overcoming the drawbacks of some existing low‐density solvent liquid microextraction methods, which require special devices, large volumes of organic solvents, or complicated operation procedures.     

Determination of chlorophenols in water using dispersive liquid–liquid microextraction coupled with water‐in‐oil microemulsion electrokinetic chromatography in normal stacking mode

The current routes to couple dispersive liquid–liquid microextraction with capillary electrophoresis are the evaporation of water immiscible extractants and the back‐extraction of analytes. In this study, a new methodology for this combination using water‐in‐oil microemulsion electrokinetic chromatography coupled with normal stacking mode on‐line sample concentration was developed to analyze chlorophenols in water samples. The analytes were extracted with tributyl phosphate and the extractant dilution (3×) was directly injected into an electrophoresis buffer (7.7 cm) containing 5% sodium dodecyl sulfate, 78% 1‐butanol, 2% 1‐heptane, and 15% sodium acetate solution (pH 8.0). This proposed method is very simple and convenient compared to the conventional procedures. The key parameters affecting separation and concentration were systematically optimized. Under the optimized conditions, dispersive liquid–liquid microextraction contributed an enrichment factor of 45–50, and the overall sensitivity improvement was 312–418‐fold. Limits of detection between 1.4 and 3.0 ng/mL and limits of quantification between 4.5 and 10.2 ng/mL were achieved. Acceptable repeatability lower than 3.0% for migration time and 9.0% for peak areas were obtained. The developed method was successfully applied for analysis of the chlorophenols in real water samples.     

Surfactant‐assisted dispersive liquid–liquid microextraction combined with field‐amplified sample stacking in capillary electrophoresis for the determination of mexiletine and lidocaine

A sensitive method for the determination of mexiletine and lidocaine using surfactant‐assisted dispersive liquid–liquid microextraction coupled with capillary electrophoresis was developed. Triton X‐100 and dichloromethane were used as the dispersive agent and extraction solvent, respectively. After the extraction, mexiletine and lidocaine were analyzed using capillary electrophoresis with ultraviolet detection. The detection sensitivity was further enhanced through the use of field‐amplified sample stacking. Under optimal extraction and stacking conditions, the calibration curves were linear over a concentration range of 0.05–1.00 μM for mexiletine and 0.03–1.00 μM for lidocaine. The limits of detection (signal‐to‐noise ratio of 3) were 0.01 and 0.01 μM for mexiletine and lidocaine, respectively. An approximately 1141‐ to 1250‐fold improvement in sensitivity was observed for the two analytes compared with the injection of a standard solution without the surfactant‐assisted dispersive liquid–liquid microextraction and field‐amplified sample stacking procedures. This developed method was successfully applied to the determination of mexiletine and lidocaine in human urine and serum samples. Both precision and accuracy for urine and serum samples were less than 8.7 and 6.7%, respectively. The recoveries of the two analytes from urine and serum samples were 54.7–64.9% and 16.1–56.5%, respectively.     

Dispersive liquid–liquid microextraction combined with acetonitrile stacking through capillary electrophoresis for the determination of three selective serotonin reuptake inhibitor drugs in body fluids

Dispersive liquid–liquid microextraction was combined with acetonitrile stacking in capillary electrophoresis for the identification of three selective serotonin reuptake inhibitors (citalopram, fluoxetine, and fluvoxamine) in human fluids such as urine and plasma. Parameters that affect the extraction and stacking efficiency, such as the type and volume of the extraction and disperser solvent, extraction time, salt addition for dispersive liquid–liquid microextraction, and sample matrices, pH, and concentration of the separation buffer for stacking, were investigated and optimized. Under optimum conditions, the enrichment factors were in the range of 1195–1441. Limits of detection ranged from 1.4 to 1.7 nM for the target analytes. Calibration graphs displayed satisfied linearity with R² greater than or equal to 0.9978, and relative standard deviations of the peak area analysis were in the range of 2.9–5.0% (n = 3). The recoveries of all tricyclic antidepressant drugs from urine and plasma were in the range of 77–117 and 79–106%, respectively. The findings of this study show that dispersive liquid–liquid microextraction acetonitrile‐stacking capillary electrophoresis is a rapid and convenient method for identifying tricyclic antidepressant drugs in urine and plasma.     

Comparison of two ultrasound‐enhanced microextractions combined with HPLC for determining acaricides in water

An ultrasound‐enhanced in situ solvent formation microextraction has been developed first time and compared with ultrasound‐enhanced ionic‐liquid‐assisted dispersive liquid–liquid microextraction for the HPLC analysis of acaricides in environmental water samples. A ionic liquid ([C₈MIM][PF₆]) was used as the green extraction solvent through two pathways. The experimental parameters, such as the type and volume of both of the extraction solvent disperser solvent, ultrasonication time, and salt addition, were investigated and optimized. The analytical performance using the optimized conditions proved the feasibility of the developed methods for the quantitation of trace levels of acaricides by obtaining limits of detection that range from 0.54 to 3.68 μg/L. The in situ solvent formation microextraction method possesses more positive characteristics than the ionic‐liquid‐assisted dispersive liquid–liquid microextraction method (except for spirodiclofen determination) when comparing the validation parameters. Both methods were successfully applied to determining acaricides in real water samples.