title: Preparation and characterization of superparamagnetic molecularly imprinted polymers for selective adsorption and separation of vanillin in food samples.
abstract: Novel water-compatible superparamagnetic molecularly imprinted polymers (M-MIPs) were prepared by coating superparamagnetic Fe3O4 nanoparticles with MIPs in a methanol-water reaction system. The M-MIPs were used for the selective adsorption and separation of vanillin from aqueous solution. The M-MIPs were characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and scanning electron microscopy (SEM). Results indicated that a core-shell structure of M-MIPs was obtained by coating a layer of silica and MIPs on the surface of the Fe3O4 nanoparticles. The obtained M-MIPs possess a loose and porous structure and can be rapidly separated from the solution using a magnet. The adsorption experiments showed that the binding capacity of the M-MIPs was significantly higher than that of the superparamagnetic non-molecularly imprinted polymers (M-NIPs). Meanwhile, the adsorption of M-MIPs reached equilibrium within 100 min, and the apparent maximum adsorption quantity (Qmax) and dissociation constant (Kd) were 64.12 μmol g(-1) and 58.82 μmol L(-1), respectively. The Scatchard analysis showed that homogeneous binding sites were formed on the M-MIP surface. The recoveries of 83.39-95.58% were achieved when M-MIPs were used for the pre-concentration and selective separation of vanillin in spiked food samples. These results provided the possibility for the separation and enrichment of vanillin from complicated food matrices by M-MIPs.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University , Nanchang, Jiangxi 330047, People's Republic of China.
authors.forename: Fangjian
authors.initials: F
authors.lastname: Ning
authors.forename: Hailong
authors.initials: H
authors.lastname: Peng
authors.forename: Liling
authors.initials: L
authors.lastname: Dong
authors.forename: Zhong
authors.initials: Z
authors.lastname: Zhang
authors.forename: Jinhua
authors.initials: J
authors.lastname: Li
authors.forename: Lingxin
authors.initials: L
authors.lastname: Chen
authors.forename: Hua
authors.initials: H
authors.lastname: Xiong
mesh_terms: D000327:Adsorption; D000818:Animals; D001547:Benzaldehydes / Q000737:chemistry / Q000302:isolation & purification*; D002099:Cacao / Q000737:chemistry*; D002417:Cattle; D005503:Food Additives / Q000737:chemistry / Q000302:isolation & purification*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008892:Milk / Q000737:chemistry*; D054802:Molecular Imprinting; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D016062:Porosity; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D001547:Benzaldehydes; D005503:Food Additives; D058185:Magnetite Nanoparticles; D011108:Polymers; C100058:vanillin
keywords: magnetic molecularly imprinted polymers; selective adsorption; superparamagnetism; vanillin; water-compatible