Abstract: BACKGROUND
Some trace amounts of urea herbicide residues can be transferred to humans via the food chain, being potentially harmful to human health. The development of robust analytical methodology for effective sample preparation and simultaneous determination of the herbicide residues in vegetable samples is required for achieving food safety.
RESULTS
The diuron-molecularly imprinted powers (MIPs) synthesized have excellent affinity and high selectivity to phenylureas (monolinuron, isoproturon, diuron, and linuron) and tebuthiuron. A novel automated procedure with better selectivity for vegetable sample treatment was developed by integrated matrix solid phase dispersion-accelerated solvent extraction-clean up in situ. Five herbicides can be baseline separated with runtime down to 5 min by ultra-performance liquid chromatography, and good linearity was obtained with correlation coefficient (r) of 0.9999. The method limit of quantification was in a range of 0.8-2.3 μg kg-1. Diuron residue in cherry tomato sample was found to be 40 μg kg-1.
CONCLUSION
The developed method has satisfactory selectivity, good linearity, high sensitivity and accuracy as well as speediness, and can ensure rapid selective extraction and sensitive multi-residue analysis at low μg kg-1 level of the herbicides in vegetable food.
Author keywords: phenylureas, tebuthiuron herbicides, vegetables, ultra-performance liquid chromatography, selective accelerated solvent extraction, clean up in situ