Abstract
Highly sensitive methods for trace-level aflatoxin determination are indispensable for cereal food safety and public health protection. This study developed a ZrO(2)-assisted QuEChERS-UHPLC-MS/MS method for the simultaneous determination of AFB(1), AFB(2), AFG(1), and AFG(2) in maize, wheat, rice, and soybean. Systematic optimization identified acetonitrile as the optimal extraction solvent and 10 mg ZrO(2) in combination with PSA, C(18), and GCB as the optimal cleanup formulation, providing recoveries of 107.33-111.60%. Chromatographic baseline separation was achieved within 8.0 min using a moderate gradient program. The method exhibited excellent linearity (R(2) > 0.999) with LODs of 0.15-0.25 µg/kg and LOQs of 0.50-0.75 µg/kg. Negligible matrix effects (0.85-1.02) validated the efficacy of ZrO(2)-assisted cleanup in eliminating co-extractive interferences in maize. Satisfactory accuracy (recoveries of 86.66-111.04%) and precision (RSDs < 14%) were obtained across all matrices. The method demonstrated consistent performance across diverse cereal and soybean matrices, fulfilling international regulatory requirements for routine aflatoxin monitoring in agricultural commodities.