Well-Defined Nanostructured Surface-Imprinted Polymers for Highly Selective Magnetic Separation of Fluoroquinolones in Human Urine

Abstract

The construction of molecularly imprinted polymers on magnetic nanoparticles gives access to smart materials with dual functions of target recognition and magnetic separation. In this study, the superparamagnetic surface-molecularly imprinted nanoparticles were prepared via surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization using ofloxacin (OFX) as template for the separation of fluoroquinolones (FQs). Benefiting from the living/controlled nature of RAFT reaction, distinct core-shell structure was successfully constructed. The highly uniform nanoscale MIP layer was homogeneously grafted on the surface of RAFT agent TTCA modified Fe3O4@SiO2 nanoparticles, which favors the fast mass transfer and rapid binding kinetics. The target binding assays demonstrate the desirable adsorption capacity and imprinting efficiency of Fe3O4@MIP. High selectivity of Fe3O4@MIP toward FQs (ofloxacin, pefloxacin, enrofloxacin, norfloxacin, and gatifloxacin) was exhibited by competitive binding assay. The Fe3O4@MIP nanoparticles were successfully applied for the direct enrichment of five FQs from human urine. The spiked human urine samples were determined and the recoveries ranging from 83.1 to 103.1% were obtained with RSD of 0.8-8.2% (n = 3). This work provides a versatile approach for the fabrication of well-defined MIP on nanomaterials for the analysis of complicated biosystems.

Molecularly imprinted polymers with multi-functionality

“…[25]). In particular, the grafting-from synthesis of the MIP layer can be achieved using different living and/or controlled radical polymerization techniques (atom-transfer radical polymerization (ATRP) and RAFT polymerization), which enable more precise control of the MIP layer on the supporting nanoparticles [26,27].…”

Synthesis of magnetic molecularly imprinted polymers by reversible addition fragmentation chain transfer strategy and its application in the Sudan dyes residue analysis

“…With the RAFT agent modified on the surface of Fe 3 O 4 @SiO 2 , the MIP layer could be grafted from the inorganic Fe 3 O 4 @SiO 2 surface. According to the literature [12], a two-step-temperature RAFT polymerization was used. At the initial reaction temperature of 50 • C, the oligomer layer was formed on the surface of the RAFT agent-modified SiO 2 shell.…”

“…This methodology allows the synthetic tailoring of macromolecules with complex architectures with predetermined molecular weight, terminal functionality, and narrow molecular weight distribution [12]. Benefiting from its controlled/living property, the well-defined MIPs layer can be easily introduced on the surface of supporting substrate, and thus significantly facilitates their applications in complicated matrixes [13].…”

“…Thus, a sensitive and faster method for the identification and quantification of such Sudan dyes in foods is required urgently. Although MMIPs developed by RAFT methodology [12,[28][29][30][31] and the separation of Sudan dyes from chilli powder by MIPs [32][33][34] are reported, the MMIP made by RAFT technology for the extraction and separation of Sudan dyes have never been reported so far.…”

Preparation of photonic-magnetic responsive molecularly imprinted microspheres and their application to fast and selective extraction of 17β-estradiol

“…That is, the resultant stimuli-responsive MIPs (SR-MIPs) act like a switch with the ability of reversible uptake and release of template/target molecules upon alternate external stimuli [23]. Till now, various SR-MIPs have been prepared, such as pH [24], temperature [25,26], photonic [27,28], and magnetic [29,30] ones. Among these external stimuli factors, photoirradiation is one of the most frequently used external stimuli for SR-MIPs due to its convenience to apply, easiness to control, and superior cleaning [31,32].…”