High-throughput quantification of butachlor by DART-MS/MS coupled with micro-solid-phase extraction and dual fragmentation to enhance selectivity and sensitivity.

A novel and rapid analytical assay based on direct analysis in real-time tandem mass spectrometry (DART-MS/MS) technology was established for quantification of butachlor in this study. The assay incorporated micro-solid-phase extraction (μ-SPE) for sample pretreatment, with acetochlor as an internal standard. Quantification was achieved via transitions from [M + H] precursor ions to primary and secondary fragment ions at m/z 312.1 → 238.0 → 162.1 (butachlor) and 270.1 → 224.1 → 148.0 (acetochlor). This chromatography-free approach eliminated reliance on mobile phases and chromatographic instrumentation, significantly improving analytical throughput (0.4 min/sample) while reducing environmental impact. Method validation demonstrated linearity over 0.5-100 ng/mL (R > 0.995), with intra-/inter-day precision < 13.1% and accuracy ranging from -6.00% to 11.0%. The assay was used to evaluate the cellular uptake kinetics of butachlor in MCF-7 cells. These findings underscore the utility of DART-MS/MS assay for rapid environmental and toxicological assessments while highlighting potential safety concerns associated with butachlor exposure. The integration of DART-MS/MS with μ-SPE offers a sustainable alternative to conventional bioanalytical workflows, combining speed, sensitivity, and reduced chemical consumption for ecotoxicological studies.