Modified dSPE combined with ultra-high-performance liquid chromatography tandem mass spectrometry to determine bongkrekic acid, iso-bongkrekic acid, and toxoflavin in wet rice noodles

In this study, a modified dSPE-UPLC-MS/MS method was developed for the simultaneous determination of bongkrekic acid (BA), iso-bongkrekic acid (IBA), and toxoflavin (TF) in wet rice noodles, achieving the quantification of all three toxins in a single extraction. When the samples were extracted with 3% acetic acid–acetonitrile, purified by the modified dSPE method, and determined by UPLC-MS/MS, high sensitivity (limit of detection of 0.20 and 0.50 μg/kg and limit of quantification of 0.40 and 1.00 μg/kg for BA/IBA and TF, respectively) and precision(relative standard deviation<5%), and satisfactory recoveries (85.7%∼ 99.8%) were obtained. This method was successfully applied to monitor the changes in the contents of the three toxins in wet rice noodle medium samples inoculated with Burkholderia gladioli pv. Cocovenenan 83756 at different incubation times (0, 4, 8, 12, 16, 20, 24, 36, 48, and 60 h). The production of BA, IBA and TF was detected simultaneously in the samples after 16 h of incubation. • Simultaneous determination of bongkrekic acid, iso- bongkrekic acid, and toxoflavin in a single extraction was achieved. • A modified dSPE purification tube was used. • Simultaneous production of all three toxins was detected in wet rice noodles after 16 h of contamination by Burkholderia gladioli pv. cocovenenans. • The modified dSPE purification tube provides some reference for the development of related kits.