A method for the design and study of enzyme microstructures formed by means of a flow-through microdispenser
Author
Summary, in English
Micrometer-sized enzyme grids were fabricated on gold surfaces using a novel method based on a flow-through microdispenser. The method involves dispensing very small droplets of enzyme solution (similar to 100 pL) during the concomitant relative movement of a gold substrate with respect to the nozzle of a microdispenser, resulting in enzyme patterns with a line width of similar to 100 mum. Different immobilization methods have been evaluated, yielding either enzyme monolayers using functionalized self-assembled thiol monolayers for covalent binding of the enzyme or enzyme multilayers by cross-linking or entrapping the enzymes in a polymer film. The latter immobilization techniques allow the formation of coupled multienzyme structures. On the basis of this feature, coupled bienzyme (glucose oxidase and catalase) or three-enzyme (alpha -glucosidase, mutarotase, and glucose oxidase) microstructures consisting of line patterns of one enzyme intersecting with the patterned lines of the other enzyme(s) were fabricated. By means of scanning electrochemical microscopy (SECM) operated in the generator-collector mode, the enzyme microstructures and their integrity were visualized using the localized detection of enzymatically produced/consumed H2O2. A calibration curve for glucose could be obtained by subsequent SECM line scans over a glucose oxidase microstructure for increasing glucose concentrations, demonstrating the possibility of obtaining localized quantitative data from the prepared microstructures. Possible applications of these enzyme microstructures for multianalyte detection and interference elimination and for screening of different biosensor configurations are highlighted.
Publishing year
2001
Language
English
Pages
4254-4261
Publication/Series
Analytical Chemistry
Volume
73
Issue
17
Document type
Journal article
Publisher
The American Chemical Society (ACS)
Topic
- Analytical Chemistry
Keywords
- SCANNING ELECTROCHEMICAL MICROSCOPY
- DIP-PEN NANOLITHOGRAPHY
- NANOSTRUCTURES
- CHROMATOGRAPHY
- FABRICATION
- GENERATION
- ELECTRODE
- DISPENSER
- SURFACES
Status
Published
ISBN/ISSN/Other
- ISSN: 1520-6882