title: Silica nanotubes for lysozyme immobilization.
abstract: Silica nanotubes were synthesized and used as enzyme immobilization carriers. The immobilization profiles were described by the adsorption of lysozyme molecules from aqueous solution onto the hydrophilic silica surface. The driving force of the adsorption, structure changes in the immobilized lysozyme molecules, and enzymatic activities were investigated. A study of the zeta potentials of silica with and without the immobilized lysozyme showed that there was an increase in the isoelectric point with the increase in the loading amount of lysozyme. FTIR spectra indicated that protein secondary structure was maintained well in the immobilized molecules. It was observed that enzymatic activities first increased and then decreased with increasing surface coverage of silica nanotubes by lysozyme, which suggested that the overlap and aggregation of lysozyme molecules reduced enzymatic activities of the adsorbed lysozyme molecules at high surface coverage.
authors.affiliation: Key Lab for Nanomaterials, Ministry of Educations, Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Ding
authors.forename: Lei
authors.initials: L
authors.lastname: Shao
authors.forename: Run-Jing
authors.initials: RJ
authors.lastname: Liu
authors.forename: Qing-Gui
authors.initials: QG
authors.lastname: Xiao
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D004789:Enzyme Activation; D004800:Enzymes, Immobilized / Q000737:chemistry*; D009113:Muramidase / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D010316:Particle Size; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000138:chemical synthesis / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D004800:Enzymes, Immobilized; D014867:Water; D012822:Silicon Dioxide; D009113:Muramidase