Innovative magnetic effervescence‑assisted microextraction for ensuring food safety: rapid monitoring of pyrethroid residues in Chrysanthemum morifolium Ramat

Ensuring the safety of widely consumed floral tea requires robust methods for monitoring pesticide residues. Herein, an innovative magnetic effervescence-assisted liquid-liquid extraction (MEALLE) method was developed for the rapid detection of pyrethroids in Chrysanthemum morifolium Ramat ( C. morifolium ). Effervescent tablets containing CO 2 /H + donors, Fe 3 O 4 , and carboxylated multi-walled carbon nanotubes were prepared via one-pot grinding-and-pressing preparation. During extraction, the tablet was introduced into C. morifolium powder pre-moistened with acidified acetonitrile as the extracting solvent. By integrating effervescence, salting-out, and magnetic aggregation, this method simplified the sample preparation procedure, eliminated the need for vortexing and centrifugation, and reduced the total time to approximately 3 min. Coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS), the method exhibited excellent linearity ( R 2  > 0.998), sensitivity (limits of quantification: 1.6–4.1 μg kg −1 ), accuracy (recovery: 73.9–108.7%), and precision (relative standard deviations < 5.7%). Application of the MEALLE method to commercial C. morifolium samples further validated its robustness and versatility. Overall, this approach provide a time-effective, equipment-independent solution for pesticide residue analysis that is independent of auxiliary equipment during the sample pretreatment, thereby serving as a valuable tool for ensuring the safety of processed floral products.