Baocheng Ji,Wenhao Zhao,Xu Xu,Yu Han,Mingsha Jie,Gaigai Xu,Yanhong Bai
The purpose of this study was to develop a modified QuEChERS method based on melamine sponge for rapid determination of multi-class veterinary drugs in milks by UPLC-MS/MS. Through simple infiltration and extrusion, fast and convenient matrix purification could be achieved within several seconds, and there was no need of extra phase separation operations. Good linearity with correlation coefficient (R 2 ) ≥0.999 was obtained for all drugs in the range of 2~500 µg·kg −1 . The obtained matrix effects were within ±20% for all monitored drugs. The recoveries of all monitored drugs ranged from 60.7% to 116.0% at three spiked levels (50, 100, and 200 µg·kg −1 ), with relative standard deviations less than 7.4%. Comparatively low LODs and LOQs were obtained in the ranges of 0.1~3.8 µg·kg −1 and 0.2~6.3 µg·kg −1 , respectively. Compared with conventional purification adsorbents, melamine sponge yielded an equal or higher purification performance with matrix removal rate as high as 52.5% and acceptable recoveries in range of 60%-120% for all monitored drugs. The satisfactory results have demonstrated the good potential of melamine sponge in matrix purification for rapid determination of multiclass residues in food safety.
The complicated food matrix seriously limits the one-time test for the potential food hazards in non-targeted analysis. Accordingly, developing advanced sample pretreatment strategy to reduce matrix effects is of great significance. Herein, newly-integrated hollow-structured covalent organic frameworks (HCOFs) with large internal adsorption capacity and target-matched pore size were synthesized via etching the core-shell structured COFs. The as-prepared HCOFs could be directly applied for matrix clean-up of vegetable samples, while further modification of polydopamine (PDA) network facilitated application for animal samples. Both HCOFs and HCOFs@PDA with the comparable sizes to the matrix interference gave excellent adsorption performance to targets, achieving satisfied recoveries (70%–120%) toward 90 pesticides and 44 veterinary drugs in one-test, respectively. This work showed the great potential of the facile-integrated HCOFs with high stability and customized size to remove interference matrix and offered a universal strategy to achieve simultaneous screening of hazards with considerable quantity in high-throughput non-targeted analysis.
Hongkai Zhang,Jing Wang,Xianfeng Huang,Rongfei Peng,Juan Du,Han Xu,Chaoyang Long,Jialiang Pan
The analysis of lipophilic shellfish toxins (LSTs) in foods is severely hampered by matrix interference and laborious sample preparation. To address these issues, we developed a split-flow in-situ matrix cleanup electroextraction (SF/ISMC-EE) method coupled with LC-MS/MS. This approach tackles two major limitations in electric field-assisted sample preparation (EFASP): bubble formation and difficulty of direct extraction from complex solid matrices. SF/ISMC-EE uses a multi-channel split-flow design to suppress bubbles, enabling high-voltage rapid enrichment (300 s). Chitosan-mediated in-situ cleanup releases analytes and blocks impurity co-extraction, eliminating need for matrix-matched calibration. The “electric field + cleanup materials” strategy allows direct electroextraction from solid/semi-solid foods, integrating extraction, cleanup, and enrichment. As the first EFASP method applied to LST analysis, it was validated with certified reference materials and real samples, demonstrating high accuracy, precision, and low detection limits meeting EU regulations. This work provides a robust and efficient tool for food safety monitoring.
危险品化学品经营许可证（带存储）