Determination of piperidinium ionic liquid cations in environmental water samples by solid phase extraction and hydrophilic interaction liquid chromatography

High-sensitivity liquid chromatography-tandem mass spectrometry quantitative for alkyl imidazolium ionic liquids in human serum: Advancing biomonitoring of human exposure concerns

Alkyl imidazolium ionic liquids (Cn[MIM]), initially heralded as eco-friendly green solvents for diverse industrial applications, have increasingly been recognized fortheir biodegradability challenges and multiple biotoxicity. Despite potential health risks, research into the effects of Cn[MIM] on human health remains scarce, particularly regarding their detection in biological serum samples. This study validated a matrix-matched calibration quantitative method that utilizes solid-phase extraction (SPE) coupled with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The method was used to analyze the presence of 10 ionic liquids (ILs) with varying alkyl carbon chain lengths (C2-C12) across 300 human serum samples. Efficient separation was achieved using optimized SPE conditions and a BEH C18 column with an appropriate mobile phase. Results demonstrated a strong linear relationship (0.05-100 ng/mL; R2 = 0.995-0.999), with detection and quantification limits with detection and quantification limits ranging from 0.001 to 0.107 ng/mL and 0.003-0.355 ng/mL, respectively. Intraday and inter-day precisions were 0.85-6.99 % and 1.50-7.46 %, with recoveries between 82 and 113 %. The validated method detected C6MIM in 19 % of samples and C8MIM in 8.3 % of samples, with concentrations ranging from 0.02 to 111.70 μg/L and 0.09-16.99 μg/L, respectively, suggesting a potential risk of human exposure. This underscores the importance of robust detection methods in monitoring environmental and human health impacts of alkyl imidazolium compounds.

Ionic liquids as potentially hazardous pollutants: Evidences of their presence in the environment and recent analytical developments

Ionic liquids (ILs) are considered to be very promising group of chemicals and the number of their potential applications is growing rapidly. However, while these compounds were originally proposed as a green alternative to classical solvents, there are certain doubts as to whether this classification is correct. Although in recent years there have been first reports published proving the presence of some ILs in the environment and even in human blood, at this point the scale of this possible problem is not yet fully understood. However, there is no doubt that as the number of ILs applications increases, analytical capabilities for rapid detection of possible environmental contamination should be also considered. Therefore, in this review paper, recent evidences for the ILs environmental contamination as well as analytical achievements related to the extraction of ILs from various environmental matrices have been summarized and important gaps and future perspectives have been pointed out. Based on the presented data it might be concluded that there is the urgent need for further development towards risk assessment of these potential environmental contaminants.

Magnetic microsphere sorbent on CaCO3 templates: Simple synthesis and efficient extraction of trace carbamate pesticides in fresh produce

Polypyrrole magnetic microspheres were synthesized and used to extract carbaryl, carbofuran, and methomyl before analysis by a high-performance liquid chromatography with diode array detection. Under optimal conditions, four times the preconcentration was achieved with the use of only 1.2 mL of sample. Good linearity with ranges of 3.0-7.5 × 10³, 6.0-4.5 × 10³, and 15-3.0 × 10³ ng kg^-1 and limits of detection of 1.37 ± 0.10, 4.7 ± 1.2, and 10.1 ± 5.7 ng kg^-1 were obtained, respectively. Good reproducibility (RSDs < 5%) was achieved over 24 cycles of extraction and regeneration. Good accuracy (recoveries 81.6 ± 1.5%-108.3 ± 2.2%) and good precision (RSDs 0.11%-4.5%) were obtained. Carbaryl was detected in apple (2.75 ± 0.23 ng kg^-1), carbofuran in tomato (11.34 ± 0.61 ng kg^-1), and methomyl in watermelon (34.7 ± 1.7 ng kg^-1). The relative expanded uncertainty of the measurement method was less than 14% for all three pesticides.

Separation and indirect ultraviolet detection of ferrous and trivalent iron ions by using ionic liquids in ion chromatography

A method of simultaneous separation and indirect ultraviolet detection of different valence iron ions Fe²⁺ and Fe³⁺ by using ionic liquids as mobile phase additives and ultraviolet absorption reagents on a cation exchange column functionalized with carboxylic acid group was developed. The effects of ionic liquids, organic acids, detection wavelength, etc. on separation and detection of Fe²⁺ and Fe³⁺ were investigated and the mechanism was discussed. The pyridinium and imidazolium ionic liquids were not only ultraviolet absorption reagents of indirect ultraviolet detection but also effective components for separating Fe²⁺ and Fe³⁺ . The separation and detection of Fe²⁺ and Fe³⁺ can be achieved using 0.5 mmol/L pyridinium ionic liquid-1.2 mmol/L methanesulfonic acid as the mobile phase. The determination of Fe²⁺ and Fe³⁺ had a good linear relationship in the concentration range of 1-100 mg/L. The limits of detection of Fe²⁺ and Fe³⁺ were 0.12 and 0.09 mg/L, respectively. This method was applied to the actual sample detection in the field of medical analysis. The spiked recoveries were between 97.3 and 99.5%, and the relative standard deviations were less than 0.6%. The method is simple, accurate, and reliable, and is an analytical method with universal and practical value.

Isolation of Aflatoxin B1 from Moldy Foods by Solid-Phase Extraction Combined with Bifunctional Ionic Liquid-Based Silicas

A solid-phase extraction method was developed by using new bifunctional ionic liquid-based silicas as sorbents to isolate aflatoxin B1 from moldy corn and peanut. Firstly, according to the adsorption efficiency, two sorbents imidazolium chloride-butylimidazolium chloride-based silica (Sil@BIm-Im) and imidazolium chloride-hexylimidazolium chloride-based silica (Sil@HIm-Im) were selected. The RSM was introduced to optimize adsorption conditions such as methanol/water ratio, time, and pH. Sil@HIm-Im, which had the highest adsorption efficiency, was used in SPE as a sorbent. After 2.0 mL of loading samples, washing solvents were optimized as 6.0 mL and 4.0 mL of water for corn and peanut, 2.0 mL of acetonitrile, and 3.0 mL of methanol. 3.0 mL of methanol/acetic acid (2.0% vol.) was investigated as an elution solvent. Finally, 0.009 μg/g and 0.023 μg/g of aflatoxin B1 were obtained in corn and peanut extract with recoveries of 80.0%-103.3% and RSDs of 2.37%-6.58%.