ISSN:
1040-0397
Keywords:
Xanthine oxidase
;
Hypoxanthine
;
Tetrathiafiulvalene
;
Tetracyanoquinodimethane
;
Rotating disk electrode
;
Biosessor
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Membrane-free amperometric biosensors have been prepared from xanthine oxidase powder (XOD) (E.C.1.2.3.2) the organic conducting salt TF-TCNQ, and silicone oil The sensor response to hypoxanthine can be described by the ezyme-kinetic Michaelis-Menten formalism with good correlation over a wide range of potential (-100 tc +300 mV vs Ag/AgCl) and pH (6.10 to 8.80)values. Measurements with rotating disk rotating disk electrodes reveal that XOD is oxidized by at least two transfer to the mediators so that the sensor can be operated in air-saturated solution. Since open circuit conditions alter the kinetic parameters of the sensor, operation in flow analysis systems is recommended. Analytical features including response time (t95 ≈ 10 seconds), detection limit (ca. 10 nM hypoxanthine), selective over interferents (e.g., ascirbate), and simplicity of preparation as well as operation and storage stability compare very favorably with other OXD biosensors.
Additional Material:
13 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/elan.1140060407
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