Simple synthesis of magnetic porous organic cages for adsorption of triphenylmethane dyes in aquatic products

Magnetic porous organic cages with nanometer size, large specific surface area, thermal stability, and super magnetism were successfully synthesized, suitable for the rapid detection of five triphenylmethane dyes in aquatic products. Using a rapid and simple method, porous organic cages (POCs) were formed on the functionalized magnetic nanoparticles in three hours. The composite materials showed excellent adsorption capacities (42.8–500 mg/g) for dyes, together with fast adsorption kinetics, thermodynamic spontaneity, and reusability. This work established a new method of analyzing five triphenylmethane dyes by HPLC. Good linearity was observed in the range of 0.01–9 μg/mL, the limits of detection and quantitation were in the range of 0.67–8 μg/kg and 3–30 μg/kg, respectively. The recoveries for the real samples were 84.1–117.2%. This research provided a new strategy for rapid and simple synthesis of magnetic porous organic cages and extends the application of POCs as an attractive sample-enrichment adsorbent for triphenylmethane dyes analysis.