Popping candy-assisted dispersive liquid-liquid microextraction for enantioselective determination of prothioconazole and its chiral metabolite in water, beer, Baijiu, and vinegar samples by HPLC

Determination of chiral prothioconazole and its chiral metabolite in water, juice, tea, and vinegar using emulsive liquid-liquid microextraction combined with ultra-high performance liquid chromatography

Emulsive liquid-liquid microextraction (ELLME), a simple, rapid, and environmentally friendly technique, was established to identify chiral prothioconazole and its chiral metabolite in water, juice, tea, and vinegar using ultra-high-performance liquid chromatography (UPLC). Environmentally friendly extractant was mixed with pure water to prepare a high-concentration emulsion, which was added to samples to complete the emulsification and extraction in 1 s. Afterward, an electrolyte solution was added to complete the demulsification without centrifugation. ELLME did not use dispersants compared to the familiar dispersive liquid-liquid microextraction (DLLME), thus reducing the use of toxic solvents and avoiding the effect of dispersants on the partition coefficient. The linear range was from 0.01 to 1 mg/L. The limit of detection was 0.003 mg/L. The extraction recoveries ranged from 82.4 % to 101.6 %, with relative standard deviations of 0.7-5.2 %. The ELLME method developed has the potential to serve as an alternative to DLLME.

Stereoselective analysis of chiral pesticides: a review

Chiral organic pollutants, including pesticides, herbicides, medicines, flame retardants, and polycyclic musk, represent a significant threat to both the environment and human health. The presence of asymmetric centers in the structure of chiral pesticides introduces stereoisomers with distinct distributions, fates, biomagnification capacities, and cytotoxicities. In aquatic environments, pesticides, as persistent/pseudo-persistent compounds, have been detected in substantial quantities, posing severe risks to non-target species and, ultimately, public health through water supply and food exposures. In response to this environmental challenge, stereoselective analytical methods have gained prominence for the identification of pesticide/drug enantiomers in recent years. This review examines the environmental impact of chiral pesticides, emphasizing the distinct biological activities and distribution patterns of their stereoisomers. By highlighting the advancements in liquid chromatography for enantiomeric analysis, the review aims to underscore the urgent need for a comprehensive understanding of these pollutants to facilitate informed remediation strategies and ensure the safer dispersal of chiral organic pollutants in the environment, thereby addressing the potential risks they pose to ecosystems and human health. Future research should focus on developing sustainable and efficient methodologies for the precise analysis of stereoisomers in complex matrices, particularly in sewage water, emphasizing the importance of sewage processing plants in ensuring water quality.

Efficient analyses of triazole fungicides in water, honey and soy milk samples by popping candy-generated CO2 and sugaring-out-assisted supramolecular solvent-based microextraction prior to HPLC determinations

An enrichment method, namely popping candy-generated CO₂ and sugaring-out-assisted supramolecular solvent-based microextraction (PGS-SUPRA), was investigated for the determination of triazole fungicide residues in water, honey and soy milk samples. The extraction process was carried out by adding popping candies into a centrifuge tube. Consequently, rapid dispersion and mass transfer of extractants can be achieved without using dispersants and auxiliary devices, and therefore, the extraction efficiency increased. The extraction parameters affecting the efficiency of the developed method were investigated. The presented method was then analysed by high-performance liquid chromatography. Under the selected condition, the wide linearity of triazole fungicides after preconcentration by the proposed microextraction method ranged from 30 to 1000 μg L^-1 for triadimefon and from 90 to 1000 μg L^-1 for myclobutanil, tebuconazole and hexaconazole, with a coefficient for determination (R ²) greater than 0.992. The limits of detection (LODs) and limits of quantitation (LOQs) were in the range of 10-30 μg L^-1 and 30-90 μg L^-1, respectively. The precisions were assessed from the relative standard deviations (RSDs) of the retention time and peak area obtained from intra- (n = 3) and inter-day (n = 3 × 5) experiments, and were greater than 1.66% and 13.52%, respectively. Moreover, the proposed method provided high enhancement factors (EnFs) ranging from 14 to 51 folds. This technique has been prosperously applied for the extraction of fungicide residues in water, honey and soy milk samples with a recovery within the range of 60-114%. Overall, the developed method was found to be advantageous as compared with other sample preparation methods.

Hydrophobic microporous extraction on polyurethane sponges for convenient and sensitive analysis of organic molecules in water

RATIONALE

Various solvent supports have been developed to overcome solvent instability during liquid-phase microextraction. The hydrophobic polyurethane sponge (PS) possesses numerous cross-linked internal microchannels and terminal micropores that can facilitate steady solvent storage capacity, high extraction efficiency, extractant loading, and recycling convenience.

METHODS

In this study, an easy, convenient, and efficient PS-supported liquid-phase microextraction (PS-LPME) coupled with gas chromatography-mass spectrometry (GC-MS) method was developed for the trace analysis of different organic compounds in aqueous solutions. Different extraction solvents, PS dosages, stirring speeds, and extraction times were first investigated by extracting eight polycyclic aromatic hydrocarbons (PAHs: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene), and then applied for the analysis of triazines, amides, chloroacetamides, and organophosphorus compounds.

RESULTS

High enrichment factors (approximately 208-439) were observed for the monitored PAHs. Good linearities, with determination coefficients (r² ) greater than 0.9992, were achieved in the concentration range of 0.01-50 μg L^-1 . Low limits of detection and quantification were found in the ranges of 0.3-3 ng L^-1 and 1-10 ng L^-1 , respectively. At three spiked concentrations (0.1, 1, and 10 μg L^-1 ), good recoveries were obtained in the range of 91.6-118.5% with intra- and inter-day relative standard deviations of less than 6.4% and 11.7%, respectively.

CONCLUSIONS

The developed PS-LPME method coupled with GC-MS was successfully applied in the analysis of different organic compounds in aqueous solutions and has shown great convenience and satisfactory enrichment performance in microextraction analysis.

Research method of rapid determination of chiral pesticide fenpropathrin enantiomers in fruit and vegetable puree by supercritical fluid chromatography

A method is firstly established for the separation and determination of fenpropathrin enantiomer residues in apple puree, strawberry puree, and tomato puree considered as a supplementary food for infants by supercritical fluid chromatography. After the sample was extracted with acetonitrile and cleaned up by a solid phase extraction column, then it's separated by a CHIRALPAK AD-3 chiral column with a gradient elution at a flow rate of 1.0 mL/min using methanol and supercritical carbon dioxide as the mobile phase, detected by ultraviolet detector at 230 nm wavelength and quantified with the external standard method. The limits of quantification of the two fenpropathrin enantiomers were both 0.2 mg/kg, the linear ranges were 1.0-20.0 mg/L with linear correlation coefficients greater than 0.9992, the recoveries in the spiked samples at 0.2, 0.4 and 2.0 mg/kg were from 80.6% to 105%, and the relative standard deviation reached 2.6%-7.7%. This method has the advantages of convenient operation, good resolution and environmental protection, which can satisfy the requirement of determination for fenpropathrin enantiomer residues in fruit and vegetable puree as a supplementary food for infants. This article is protected by copyright. All rights reserved.

Liquid-Phase Microextraction Approaches for Preconcentration and Analysis of Chiral Compounds: A Review on Current Advances

Chirality is a critical issue in pharmaceutics, forensic chemistry, therapeutic drug monitoring, doping control, toxicology, or environmental investigations as enantiomers of a chiral compound can exhibit different activities, i.e., one enantiomer can have the desired effect while the other one can be inactive or even toxic. To monitor enantioselective metabolism or toxicokinetic/toxicodynamic mechanisms in extremely low content in biological or environmental matrices, sample preparation is vital. The present review describes current status of development of liquid-phase microextraction approaches such as hollow fiber liquid-phase microextraction (HF-LPME), electromembrane extraction (EME), dispersive liquid-liquid microextraction (DLLME), and supramolecular solvent-based microextraction (SSME), used for sample preparation of enantiomers/chiral compounds. The advantages and limitations of the above techniques are discussed. Attention is also focused on chiral separation approaches commonly applied to study the stereo-selective metabolism or toxicokinetic/toxicodynamic mechanisms of enantiomers in the biological and environmental samples.

Prothioconazole and prothioconazole-desthio induced different hepatotoxicities via interfering with glycolipid metabolism in mice

Prothioconazole (PTA), a new triazole fungicide, has been widely used worldwide. A recent study has confirmed that PTA and its main metabolite prothioconazole-desthio (dPTA) interfere with the liver metabolism in reptiles. However, little is known about liver toxicity of these two pollutants in mammals. Here, female mice were orally exposed to PTA (1.5 mg/kg body weight/day) and dPTA (1.5 mg/kg body weight/day) for 30 days. Additionally, growth phenotype and indexes related to serum and liver function were examined. Using metabolomics and gene expression analysis, PTA- and dPTA-induced hepatotoxicity was studied to clarify its potential underlying mechanism of action. Together, the results indicated that PTA and dPTA exposure caused changes in growth phenotypes, including elevated blood glucose levels, triglyceride accumulation, and damage of liver function. Additionally, exposure to PTA and dPTA caused changes in genes and metabolites related to glycolipid metabolism in female mice, thereby interfering with the pyruvate metabolism and glycolysis/gluconeogenesis pathways, ultimately leading to hepatic metabolism disorders. In particular, the effect of dPTA on hepatotoxicity has been proven to be more significant than that of PTA. Thus, these findings help us understand the underlying mechanism of action of PTA and dPTA exposure-induced hepatotoxicity in mammals and possibly humans.

Enantiomeric separation of prothioconazole and prothioconazole-desthio by Capillary Electrophoresis. Degradation studies in environmental samples

In this work, two analytical methodologies by Capillary Electrophoresis were developed. The first one enabled the rapid and cost-effective enantioseparation of prothioconazole and was applied to the analysis of prothioconazole-based commercial agrochemical formulations. The second methodology enabled the simultaneous enantioseparation of prothioconazole and its metabolite prothioconazole-desthio and was applied to degradation studies of both compounds in soil and sand samples. The influence of several experimental variables was investigated to develop both methodologies. The separation of prothioconazole enantiomers was achieved in 4.5 min with a resolution of 2.8 employing a neutral cyclodextrin (heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin). Given the nature of prothioconazole-desthio, a neutral cyclodextrin cannot be used for its chiral separation. For this reason, the simultaneous enantioseparation of prothioconazole and prothioconazole-desthio was achieved in 5.5 min with resolution values of 1.9 and 8.2, respectively, using a negatively charged cyclodextrin (sulfated-γ-cyclodextrin). The analytical characteristics of the developed methodologies were evaluated and both methods showed good performance to be applied to the quantitation of the enantiomers of prothioconazole in commercial agrochemical formulations (LOD 0.7 mg L^-1) and to carry out degradation studies for both compounds in environmental matrices (LODs lower than 0.9 and 1.3 mg L^-1 for prothioconazole and prothioconazole-desthio enantiomers, respectively). The recovery values obtained were in the range between 94-104 % for the agrochemical formulations, between 96-99 % for the sand samples and between 97-100 % for the soil samples.

Simultaneous detection and identification of thiometon, phosalone, and prothioconazole pesticides using a nanoplasmonic sensor array

In this work, a colorimetric sensor array has been designed for the identification and discrimination of thiometon (TM) and phosalone (PS) as organophosphate pesticides and prothioconazole (PC) as a triazole pesticide. For this purpose, two different plasmonic nanoparticles including unmodified gold nanoparticles (AuNPs) and unmodified silver nanoparticles (AgNPs) were used as sensing elements. The principle of the proposed strategy relied on the aggregation AuNPs and AgNPs through the cross-reactive interaction between the target pesticides and plasmonic nanoparticles. Therefore, these aggregation-induced UV-Vis spectra changes were utilized to discriminate the target pesticides with the help of linear discriminant analysis (LDA). Besides, we have employed the bar plots and the heat maps as visual non-statistical methods to differentiate the pesticides in a wide range of concentrations (i.e., 20-5000 ng mL^-1). Multivariate calibration plots from partial least squares (PLS)- regression indicated that the responses linearly depend on the pesticide concentrations in the range of 100-1000 ng mL^-1 with the limit of detections (LOD) of 66.8, 68.3, and 41.4 ng mL^-1, for TM, PS, and PC, respectively. Finally, the potential applicability of the proposed sensor array has been evaluated for the detection and identification of the pesticides in the mixtures, water samples, and cucumber fruit.