title: Novel molecular imprinted polymers over magnetic mesoporous silica microspheres for selective and efficient determination of protocatechuic acid in Syzygium aromaticum.
abstract: Improving sites accessibility can increase the binding efficiency of molecular imprinted polymers (MIPs). In this work, we firstly synthesized MIPs over magnetic mesoporous silica microspheres (Fe3O4@mSiO2@MIPs) for the selective recognition of protocatechuic acid (PCA). The resulting Fe3O4@mSiO2@MIPs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectrometer (FT-IR), thermo-gravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), and vibration sample magnetometer (VSM), and evaluated by adsorption isotherms/kinetics and competitive adsorption. The maximum adsorption capacity of PCA on Fe3O4@mSiO2@MIPs was 17.2mg/g (2.3 times that on Fe3O4@SiO2@MIPs). In addition, Fe3O4@mSiO2@MIPs showed a short equilibrium time (140min), rapid magnetic separation (5s) and high stability (retained 94.4% after six cycles). Subsequently, Fe3O4@mSiO2@MIPs were successfully applied for the selective and efficient determination of PCA (29.3μg/g) from Syzygium aromaticum. Conclusively, we combined three advantages into Fe3O4@mSiO2@MIPs, namely, Fe3O4 core for quick separation, mSiO2 layer for enough accessible sites, and surface imprinting MIPs for fast binding and excellent selectivity, to extract PCA from complex systems.
authors.affiliation: College of Sciences, Central South University of Forestry and Technology, Changsha 410004, China; College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China. Electronic address: xiecsu@126.com.
authors.forename: Lianwu
authors.initials: L
authors.lastname: Xie
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Junfang
authors.initials: J
authors.lastname: Guo
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Sciences, Central South University of Forestry and Technology, Changsha 410004, China.
authors.forename: Yunchu
authors.initials: Y
authors.lastname: Hu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Qingping
authors.initials: Q
authors.lastname: You
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China. Electronic address: shuyshi@gmail.com.
authors.forename: Shuyun
authors.initials: S
authors.lastname: Shi
mesh_terms: D062385:Hydroxybenzoates / Q000737:chemistry*; D060328:Magnetic Phenomena; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D008863:Microspheres; D054802:Molecular Imprinting / Q000379:methods*; D010936:Plant Extracts / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D017365:Spices
chemical_list: D062385:Hydroxybenzoates; D010936:Plant Extracts; D011108:Polymers; C009091:protocatechuic acid; D012822:Silicon Dioxide
keywords: Magnetic microsphere; Mesoporous silica; Molecularly imprinted polymers; Protocatechuic acid; Syzygium aromaticum