title: Amino-functionalized mesostructured cellular foams as carriers of glucose oxidase.
abstract: The mesostructured cellular foams (MCFs) were synthesized in aqueous hydrochloric acid by using dilute Pluronic P123 solutions in the presence of 1,3,5-trimethylbenzene (TMB) as organic cosolvent. And the amino-functionalized MCFs (NH₂-MCFs) were prepared from primary MCFs by post-synthesis method using 3-aminopropyl-trimethoxysilane (APTMS) as the chemical modifier. The SEM and TEM observations showed the similar morphologies and pore structures of both MCFs and NH₂-MCFs, indicating that the surface modification had little effect on the morphologies and pore structures. Glucose oxidase (GOD) was physically adsorbed on MCFs and NH₂-MCFs at different pH. The maximum immobilized amount of GOD on NH₂-MCFs (487 mg g⁻¹) was much higher than that of MCFs (216 mg g⁻¹) at pH 5.0. The larger loading capacity of NH₂-MCFs suggested that the electrostatic interaction was the dominant force for GOD adsorption. Furthermore, the immobilized GOD exhibited improved thermal and storable stabilities. The GOD immobilized on NH₂-MCFs (NH₂-MCFs-GOD) still maintained 80% of initial activity after incubation at 60°C for 1 h, whereas the free GOD and the GOD immobilized on MCFs (MCFs-GOD) remained only 40% and 60%, respectively. Moreover, after stored at 4°C for 30 days, the free GOD, the MCFs-GOD and the NH₂-MCFs-GOD retained 37%, 52% and 73% of initial activities, respectively. Based on these results, possible mechanisms were also discussed.
authors.affiliation: College of Materials Science and Engineering, Sichuan University, Chengdu 610064, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Guangfu
authors.initials: G
authors.lastname: Yin
authors.forename: Yi
authors.initials: Y
authors.lastname: Ding
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liao
authors.forename: Xianchun
authors.initials: X
authors.lastname: Chen
authors.forename: Zhongbing
authors.initials: Z
authors.lastname: Huang
authors.forename: Yadong
authors.initials: Y
authors.lastname: Yao
authors.forename: Ximing
authors.initials: X
authors.lastname: Pu
mesh_terms: D000327:Adsorption; D001234:Aspergillus niger / Q000201:enzymology; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D005949:Glucose Oxidase / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D016062:Porosity; D011437:Propylamines / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D055682:Viscoelastic Substances / Q000737:chemistry
chemical_list: D004800:Enzymes, Immobilized; D011437:Propylamines; D012821:Silanes; D055682:Viscoelastic Substances; C088294:3-aminopropyltrimethoxysilane; D005949:Glucose Oxidase
keywords: Amino-functionalization; Enzyme immobilization; Enzyme stability; Glucose oxidase; Mesostructured cellular foams