title: USPIO assisting degradation of MXC by host/guest-type immobilized laccase in AOT reverse micelle system.
abstract: The laccase and ultrasmall superparamagnetic iron oxide nanoparticles (USPIO) have been assembled inside the tubular mesoporous silica via co-adsorption technology to prepare host/guest-type immobilized laccase, which is applied to degrade methoxychlor (MXC) in aqueous and reverse micelle environments. The effects of various parameters on degradation of MXC were studied. Under the optimum conditions, the degradation rate could reach maximum value of 45.6 % and remain at 20.8 % after seven cycles. Moreover, the addition of small molecular compound 2, 2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) to the system could greatly improve the degradation efficiency. The MXC degradation process is a first-order reaction, and the activation energy of MXC degradation catalyzed by immobilized laccase (41.46 kJ mol(-1)) is relatively lower than that catalyzed by free laccase (44.91 kJ mol(-1)). Based on the degradation products measured by gas chromatograph-mass spectrometer (GC-MS) and nuclear magnetic resonance (NMR), the degradation mechanism of MXC has also been proposed.
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China. yxyang@ecust.edu.cn.
authors.forename: Yu-Xiang
authors.initials: YX
authors.lastname: Yang
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Na
authors.initials: N
authors.lastname: Pi
authors.affiliation: Department of Environmental Sciences, Peking University, Beijing, 100871, China.
authors.forename: Jian-Bo
authors.initials: JB
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China. huangyan@ecust.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Ping-Ping
authors.initials: PP
authors.lastname: Yao
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Yan-Jie
authors.initials: YJ
authors.lastname: Xi
authors.affiliation: State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012, China.
authors.forename: Hong-Ming
authors.initials: HM
authors.lastname: Yuan
mesh_terms: D000327:Adsorption; D052160:Benzothiazoles / Q000737:chemistry; D002384:Catalysis; D003911:Dextrans / Q000737:chemistry*; D004800:Enzymes, Immobilized / Q000737:chemistry*; D007306:Insecticides / Q000737:chemistry*; D042845:Laccase / Q000737:chemistry*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008731:Methoxychlor / Q000737:chemistry*; D008823:Micelles; D012822:Silicon Dioxide / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry
chemical_list: D052160:Benzothiazoles; D003911:Dextrans; D004800:Enzymes, Immobilized; D007306:Insecticides; D058185:Magnetite Nanoparticles; D008823:Micelles; D013451:Sulfonic Acids; C097921:ferumoxtran-10; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D012822:Silicon Dioxide; D042845:Laccase; D008731:Methoxychlor
keywords: Degradation; Host/guest-type immobilized laccase; Methoxychlor; Tubular mesoporous silica; Ultrasmall superparamagnetic iron oxide nanoparticles