title: Fabrication and characterization of core-shell magnetic chitosan nanoparticles as a novel carrier for immobilization of Burkholderia cepacia lipase.
abstract: In this study, the chitosan magnetic core-shell nanoparticles (CMNPs) was synthesized and then used as a support for immobilization of lipase. The characteristics of CMNPs, including morphology, topography and spectra type before and after immobilization were determined. The scanning electron micrographs of the CMNPs showed that they were approximately uniform spheres and the distribution chart indicated that the particles have the mean diameter of 100 nm. Kinetic parameters of Km and Vm were calculated as 1.07 mM and 29.43 U/mg for free B. cepacia lipase and 1.29 mM and 25.82 U/mg for immobilized lipase on CMNPs, respectively. The activity of immobilized lipase was 32 U/mg under optimum temperature and pH. CMNP's were used in trasesterification reaction in order to evaluate the activity of the immobilized enzyme compared to the free enzyme. Immobilization of lipase on CMNPs improved stability and total relative activity of the enzyme. It could be concluded that CMNPs be considered as a suitable carrier for enzyme immobilization.
authors.affiliation: Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB) Tehran,  ( 2) Faculty of Chemical Engineering, Noshirvani University of Technology, Babol, Iran.
authors.forename: Arezoo
authors.initials: A
authors.lastname: Ghadi
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Tabandeh
authors.forename: Soleiman
authors.initials: S
authors.lastname: Mahjoub
authors.forename: Afshin
authors.initials: A
authors.lastname: Mohsenifar
authors.forename: Farid Talebnia
authors.initials: FT
authors.lastname: Roshan
authors.forename: Razieh Shafiee
authors.initials: RS
authors.lastname: Alavije
mesh_terms: D016956:Burkholderia cepacia / Q000201:enzymology*; D048271:Chitosan / Q000138:chemical synthesis* / Q000737:chemistry*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D004951:Esterification; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000737:chemistry; D058185:Magnetite Nanoparticles; D064347:Microscopy, Electrochemical, Scanning; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D058185:Magnetite Nanoparticles; D048271:Chitosan; D008049:Lipase