Application of solid‐phase extraction: High‐resolution mass spectrometry analysis strategy in the characterization and quantification of amide herbicides in aquatic products

Carbon Nanotube-Supported Dummy Template Molecularly Imprinted Polymers for Selective Adsorption of Amide Herbicides in Aquatic Products

In this study, a carbon nanotube (CNTs)-supported dummy template molecularly imprinted polymer (DMIPs) material was synthesized and utilized for the detection of amide herbicides in aquatic products via matrix solid-phase dispersion technology (MSPD). The DMIPs material was characterized, and its adsorption kinetics and isotherm were determined, the adsorption model was established, and the selective adsorption coefficient was calculated. The extract parameters of the method were optimized and successfully employed for the separation, analysis and detection of real samples, with satisfactory detection limits and linear ranges obtained. By comparing with other methods, the CNTs@DMIPs combined with MSPD technology established in our study can effectively solve false negative problems caused by insufficient destructive force, using dummy template molecules can also address the issue of false positives caused by template molecule leakage in molecular imprinting. Overall, the method is appropriate for the separation and detection of endogenous substances from highly viscous and poorly dispersed samples and is used as a routine detection tool in the aquaculture industry.

Development of a MOF-based SPE method combined with GC-MS for simultaneous determination of alachlor, acetochlor and pretilachlor in field soil

In this work, a rapid, highly selective, reusable and effective method was developed for simultaneous determination of alachlor, acetochlor and pretilachlor in field soil by GC-MS coupled with MIL-101 based SPE. Main factors affecting the SPE by using MIL-101 were optimized. Moreover, by comparing with the other commercial materials such as C₁₈, PSA and Florisil, the MIL-101(Cr) exhibited excellent adsorption performance, which aimed at amide herbicides. On the other hand, method validation displayed excellent method performance, achieving good linearities with r² ≥ 0.9921, limits of detection between 0.25-0.45 μg kg^-1, enrichment factors ≥ 89, matrix effect in the range of ± 20%, recoveries between 86.3% and 102.4%, and RSD lower than 4.38%. The developed method was successfully applied to the determination of amide herbicides in soil taken from the wheat, corn and soybean field at different depths, where the concentration of alachlor, acetochlor and pretilachlor were in the range of 0.62-8.04 μg kg^-1. It was demonstrated that the more depth of soil, the lower of three amide herbicides. This finding could be proposed a novel method to detect the amide herbicides in the agriculture and food industry.

Cellular toxicity and pharmacokinetic study of butachlor by ultra-performance liquid chromatography-tandem mass spectrometry based on tandem mass spectrometry cubed technique

Butachlor is an aromatic amide compound that plays a role as a herbicide, a xenobiotic, and an environmental contaminant. The aim of this work was to develop a highly selective and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method based on the tandem mass spectrometry cubed technique to determine butachlor in a biological matrix. Butachlor and internal standard acetochlor were separated on a Waters Acquity ultra-performance liquid chromatography BEH C₁₈ column (2.1 × 50 mm, 1.7 μm) with gradient elution using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as mobile phases. The transitions selected for tandem mass spectrometry cubed quantitative analysis in positive ion mode were: for butachlor, mass-to-charge ratio 312.2→238.1→162.1; for acetochlor, mass-to-charge ratio 270.1→224.0→148.1. The total running time for each sample was 5.5 min. The ultra-performance liquid chromatography-tandem mass spectrometry cubed method showed a linear relationship (R² ≥ 0.995) in the concentration range of 0.5-100 ng/ml. The intra and interday accuracies are within the range of -10.6%-4.3% and precisions are between 4.48% and 13.14%. The novelty of the method is the use of tandem mass spectrometry cubed scanning mode, which improves selectivity and sensitivity. The results indicated that butachlor was cellular toxic. The safety of butachlor should be considered when it is used as a herbicide.