A hydrophilic solid phase microextraction fiber for in vivo monitoring neonicotinoid insecticides in bean sprouts

Conventional solid-phase microextraction fibers are primarily designed for detecting and analyzing of hydrophobic compounds, with limited applicability for hydrophilic compounds. This limitation restricts the in vivo application of solid-phase microextraction technology for hydrophilic substances. In the present study, a novel in vivo SPME fiber, exhibiting superior affinity for neonicotinoids, was developed. The custom-designed fiber exhibited outstanding sampling performance, robust reproducibility with an inter-fiber relative standard deviation of 6.0–10.3 %, and a low detection limit of 0.05 ng mL −1 . The accuracy of the in-house in vivo solid phase microextraction fiber was found to be comparable to that of traditional liquid-liquid extraction methods, while demonstrating superior extraction efficiency. The developed fiber was successfully employed to monitor the degradation kinetics of four neonicotinoid insecticides (acetamiprid, imidacloprid, thiacloprid, and thiamethoxam) in bean sprouts . Differences in the metabolic rates of these insecticides within the bean sprouts were revealed by the elimination kinetics. Also, their elimination half-lives followed the sequence of acetamiprid (0.42 days) > thiamethoxam (0.85 days) > imidacloprid (0.95 days) > clothianidin (1.13 days). The in vivo solid-phase microextraction fiber developed in this study provided operational simplicity and high extraction efficiency, making it a crucial tool for pesticide toxicology research and safety assessment of agricultural products.