Characterization of glucose oxidase immobilization onto mica carrier by atomic force microscopy and kinetic studies.
Glucose oxidase (E.C 1.1.3.4) immobilized onto activated surface of mica was analyzed by enzymatic kinetics and visualization with atomic force microscopy (AFM). The activity of the immobilized enzyme decreased with the decrease of concentration of gamma-aminopropyltrimethoxysilane used for the first step of activation of mica, while AFM analysis showed similar homogeneous filling of the surface with the enzyme. The comparison of enzyme activity with its surface filling revealed that there has to be additional vertical structures, which cannot be visualized by the methods of AFM. The simultaneous decrease of the silanizing agent and the concentration of the enzyme led to molecular resolution for the enzyme on the surface of mica. This allows to propose the described method also for analyzing other surfaces of solid materials with coupled biomolecules.
Institute of Organic and Bioorganic Chemistry, University of Tartu, Jakobi Str. 2, 51014 Tartu, Estonia.
Kristjan
K
Saal
Väino
V
Sammelselg
Ants
A
Lõhmus
Edith
E
Kuusk
Gerda
G
Raidaru
Toonika
T
Rinken
Ago
A
Rinken
D000538:Aluminum Silicates; D004789:Enzyme Activation; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000648:ultrastructure*; D005949:Glucose Oxidase / Q000737:chemistry* / Q000648:ultrastructure*; D018625:Microscopy, Atomic Force / Q000379:methods*; D011437:Propylamines; D012821:Silanes / Q000737:chemistry
D000538:Aluminum Silicates; D004800:Enzymes, Immobilized; D011437:Propylamines; D012821:Silanes; D005949:Glucose Oxidase; C477625:amino-propyl-triethoxysilane; C011934:mica