TITLE:
A New Biosensor for Glucose Based on Screen Printed Carbon Electrodes Modified with Tin (IV)-Oxide
AUTHORS:
Liridon Berisha, Kurt Kalcher, Ahmet Hajrizi, Tahir Arbneshi
KEYWORDS:
Biosensor; Glucose; Hydrogen Peroxide; Tin (IV)-Oxide; Blood Serum
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.4 No.6A,
June
21,
2013
ABSTRACT: Tin (IV) oxide was used as a bulk mediator in carbon
paste and carbon ink screen-printed electrodes to improve the better
performance of the carbon electrodes for the detection of hydrogen peroxide in
comparison with unmodified electrodes. A new glucose biosensor developed from
modified carbon paste electrode and coated with glucose oxidase entrapped in
Nafion was investigated with a flow injection system. The biosensor could be
operated under physiological conditions (pH 7.5, 0.1 M phosphate buffer), with
an operating potential of ?200 mV (vs. Ag/AgCl), a flow rate of the carrier of 0.2
mL/min. and an injection volume of 100 μL. The amperometric response of the
biosensor showed good linearity up to 200 mg/L with a detection limit (3σ) of 6.8 mg/L. The relative standard
deviation for the repeatability of measurements for 100 mg/L glucose was 2.9%
(n = 10 measurements) and the corresponding reproducibility was 12% (n = 5
sensors). The effect of all investigated interferences (uric acid, paracetamol,
xanthine, hypoxanthine and ascorbic acid) was not fatal and could be eliminated
by the use of the standard addition method. The new biosensor was successfully
applied to the determination of glucose in human blood plasma.