Synthesis of molecular-imprinting polymer coated magnetic nanocomposites for selective capture and fast removal of environmental tricyclic analogs

Abstract

The organic residues of tricyclic analogs (TAA) in the environment such as cyproheptadine (CYP), amitriptyline (AMI), desloratadine (DES), 8-chloroazatadine (8-CHL), ketotifen fumarate (KF), and so on, brought many negative effects on human health. Hence, a novel magnetic molecularly imprinted polymers (MMIPs) combining magnetic Fe3O4 as the core with molecularly imprinted polymer using CYP as the template molecule, was successfully synthesized for highly selective capture and removal of TAA in water rapidly. CYP was selected as a template molecule, which was attributed to its representative structure among the five tricyclic analogues, and relatively inexpensive cost. The key preparation conditions were systematically optimized. The structure, morphology and adsorption behavior of MMIPs were studied in detail. The experimental results indicate that the prepared MMIPs possess high adsorption capacity, good selectivity, and fast reaction kinetics for tricyclic analogs. The maximum adsorption capacity of MMIPs for CYP, AMI, DES, 8-CHL, and KF is 48.89, 47.14, 47.33, 46.89, and 42.14 mg/g, respectively, which is significantly higher than that of magnetic non-molecular imprinting polymerizations because of the imprinting effect, with an imprinted layer thickness of approximately 10 nm. The imprinting factors of the synthesized materials are 4.74, 5.63, 5.69, 6.91, and 5.68, respectively. Meanwhile, the recovery rate of standard addition in environmental water samples is greater than 94.77%. Therefore, the synthesized MMIPs can be used as a promising material to capture and remove TAA in water selectively and quickly.