Magnetic nanoparticles coated with a molecularly imprinted polymer doped with manganese-doped ZnS quantum dots for the determination of 2,4,6-trichlorophenol

The authors describe a multifunctional magnetic molecularly imprinted phosphorescent nanoparticle probe for the selective determination of 2,4,6-trichlorophenol (2,4,6-TCP). The probe consists of a magnetite (Fe 3 O 4 ) core that is coated with a molecularly imprinted polymer doped with Mn-doped ZnS quantum dots (QDs). The MIP was obtained by copolymerization of acrylamide, ethylene glycol dimethacrylate, and 2,4,6-TCP. The resulting nanoprobe shows strong phosphorescence (with excitation/emission peaks at 320/594 nm) due to the presence of the QDs, good magnetism, and high selectivity for 2,4,6-TCP. Under optimal detection condition, response is linear in the 0.1–30 μmol L −1 2,4,6-TCP concentration range. The imprinting factor is 8.84, and the detection limit is 35 nmol L −1 . The method was successfully applied to the determination of 2,4,6-TCP in spiked river water and waste water. Schematic of a multifunctional phosphorescent probe for 2,4,6-trichlorophenol. It consists of a magnetic core coated with a molecularly imprinted polymer shell containing Mn(II) doped ZnS quantum dots whose room-temperature phosphorescence is quenched by 2,4,6-trichlorophenol.