Research advances of porous organic framework materials on enrichment and detection of mycotoxins

Mycotoxins are a class of toxic secondary metabolites produced by fungi. These substances are carcinogenic, teratogenic, and mutagenic, and cause serious harm to the human body; thus, they have attracted wide attention worldwide. Establishing accurate, rapid, and sensitive methods for the detection of mycotoxins is of great significance. Chromatography is a commonly used technology for mycotoxin detection. However, it is challenging to use in the direct analysis of these metabolites because of the wide variety and distribution of mycotoxins, their complex sample matrix, and their very low content in actual samples. Therefore, the development of suitable sample pretreatment methods for the efficient separation and enrichment of mycotoxins is necessary. In recent years, porous organic framework materials, which are represented by metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs), have been widely applied in the sample pretreatment of mycotoxins owing to their many advantages, which include a large specific surface area, high porosity, adjustable pore size, diverse frame structures, uniform active site distribution, and modifiable structures. In addition, MOF/COF materials feature excellent fluorescence and electrochemical properties, rendering them highly suitable for mycotoxin analysis and sensing. In this article, the recent applications of MOF/COF materials in conventional sample pretreatment methods (e. g., solid-phase extraction, dispersive solid-phase extraction, magnetic solid-phase extraction, and immunomagnetic bead separation) for mycotoxin separation and enrichment are reviewed. Research on the use of MOF/COF materials for the fluorescence and electrochemical sensing of mycotoxins is also summarized. Finally, the existing challenges and future development trends of these materials are discussed and prospected to provide a reference for future research on the applications of MOF/COF materials in mycotoxin detection and analysis.