title: Effect of surface modification of low cost mesoporous SiO2 carriers on the properties of immobilized lipase.
abstract: To investigate the surface effects of low cost mesoporous SiO2 on the properties of lipase, a series of modified mesoporous SiO2 was synthesized through various alkoxysilanes reacted with hydroxyl of SiO2 (C1-SiO2, C8-SiO2, C16-SiO2, SH-SiO2, Ph-SiO2, NH2-SiO2). Particularly, ionic liquids as novel alkoxysilane were synthesized and subjected to modify the low cost mesoporous SiO2 (CH3IL-SiO2 and COOHIL-SiO2). The porcine pancreas lipase (PPL) was immobilized on the prepared materials. The activity assay indicated that the activation of enzymatic activity site was benefit from the longer alkyl chain of alkoxysilane because of the growing hydrophobic nature. Nevertheless, the loading of lipase decreased from 69% for PPL-C1-SiO2 to 59% for PPL-C16-SiO2, reflecting the growing hydrophobic property limited the immobilization yield. The characteristic of alkoxysilane group (SH-SiO2, Ph-SiO2, NH2-SiO2) was another important factor to influence immobilization efficiency and enzymatic performance besides the alkyl chain length. The immobilization efficiency of PPL-SH-SiO2, PPL-Ph-SiO2 and PPL-NH2-SiO2 maintained at least 93%. Compared with conventional alkoxysilane, the activity of PPL-CH3IL-SiO2 improved to 2.60 folds of PPL-SiO2. The immobilization efficiency of PPL-COOHIL-SiO2 was up to 97% and the relative activity was above 62% after five recycles.
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China; School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China. Electronic address: huyi@njut.edu.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Hu
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Fengjie
authors.initials: F
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China.
authors.forename: Dinghua
authors.initials: D
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China. Electronic address: biotech@njut.edu.cn.
authors.forename: He
authors.initials: H
authors.lastname: Huang
mesh_terms: D000327:Adsorption; D000818:Animals; D004800:Enzymes, Immobilized / Q000737:chemistry*; D017743:Equipment Reuse; D057927:Hydrophobic and Hydrophilic Interactions; D052578:Ionic Liquids / Q000737:chemistry; D007700:Kinetics; D008049:Lipase / Q000737:chemistry*; D008958:Models, Molecular; D010179:Pancreas / Q000737:chemistry / Q000201:enzymology; D016062:Porosity; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D013552:Swine; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D052578:Ionic Liquids; D012821:Silanes; D012822:Silicon Dioxide; D008049:Lipase
keywords: Immobilization; Ionic liquid; Lipase; Mesopore; Surface