Recently, covalent organic frameworks (COFs) as an important class of porous frameworks have been employed in analytical applications owing to their significant inherent properties such as a high specific surface area with modifiable pore size and a robust nature that leads to great stabilities. Also, COFs are flexible in design to deliberate changes in their physical or chemical properties by generating functionalized COFs or COF-based composites. Here, we summarize some important categories of COFs from the point of view of design and synthetic strategies. Subsequently, the synergistic combination aspects of COFs with other materials such as different types of magnetic, metal/metal oxide nanoparticles, silica, carbon nanomaterials, polymers, polyoxometalates (POM), MOF, and other COFs are investigated. Finally, the recent application of COFs as efficient sorbent in analytical sample preparation methods are surveyed including solid-phase extraction (SPE), dispersive solid-phase extraction (dSPE), magnetic solid-phase extraction (MSPE), and solid-phase microextraction (SPME) with emphasis on important factors that lead to increase extraction efficiency. In addition, challenges and obstacles in these approaches are discussed with perspective highlights.

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