Hernandez, P., Rodriguez, J.A., Salazar, V., Álvarez-Romero, G.A., González-Montiel, S., Castrillejo Y. Determination of glucose by flow injection analysis with amperometric detection at Fe(III)-(tris(3,5-dimethyl-1-pyrazolyl)borate)2 modified electrodes, Journal of the Mexican Chemical Society, 2011, Vol. 55, p. 120-125, ISSN 1870-249X
A modified screen printed electrode with [Fe(tris(3,5-dimethyl-1-pyrazolyl)borate)2] + [FeCl4]-, installed as part of a flow injection system, was used as an amperometric detector to determine hydrogen peroxide and glucose after on-line reaction with glucose oxidase. The influence of experimental variables on sensitivity, such asthe flow rate, injection volume and reaction coil length, was evaluatedusing a two-level factorial experimental design. Under optimal conditions, detection limits of 15 M and 0.5 mM for H2O2 and glucose, respectively, were obtained. A sampling rate of 60 determinations h-1 was achieved; the relative standard deviation of analytical measurements was <5.0%. The method was validated by comparing the obtained results with those provided by the enzymatic spectrophotometric method; no significant differences were observed (p < 0.05). Keywords: Glucose, Hydrogen peroxide, Flow injection system.