Immobilization of glucose oxidase on Fe3O4/SiO2 magnetic nanoparticles.
Glucose oxidase (GOD) was covalently immobilized onto Fe(3)O(4)/SiO(2) magnetic nanoparticles (FSMNs) using glutaraldehyde (GA). Optimal immobilization was at pH 6 with 3-aminopropyltriethoxysilane at 2% (v/v), GA at 3% (v/v) and 0.143 g GOD per g carrier. The activity of immobilized GOD was 4,570 U/g at pH 7 and 50 degrees C. The immobilized GOD retained 80% of its initial activity after 6 h at 45 degrees C while free enzyme retained only 20% activity. The immobilized GOD maintained 60% of its initial activity after 6 cycles of repeated use and retained 75% of its initial activity after 1 month at 4 degrees C whereas free enzymes retained 62% of its activity.
Key Laboratory of Fiber Optic Sensing Technology and Information Processing of Ministry of Education, Wuhan University of Technology, 430070, Wuhan, China. hjun@whut.edu.cn
Jun
J
Huang
Rong
R
Zhao
Hai
H
Wang
Wenqi
W
Zhao
Liyun
L
Ding
D001709:Biotechnology / Q000379:methods*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D052203:Ferrosoferric Oxide; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D011485:Protein Binding; D012822:Silicon Dioxide; D013696:Temperature
D004800:Enzymes, Immobilized; D012822:Silicon Dioxide; D005949:Glucose Oxidase; D052203:Ferrosoferric Oxide