Comparison of Glucose Enzyme Electrodes Based on Dispersed Rhodium Particles and Cupric Hexacyanoferrate Within Carbon Paste Transducers

Abstract

The performance of ‘first-generation’ amperometric glucose biosensors based on the dispersion of rhodium particles and metal hexacyanoferrate within carbon paste transducers is critically compared. Both bioelectrodes allow the detection of the glucose substrate at very low potentials where potential interferences are minimized. Performance characteristics of the two biosensors are compared under identical conditions. The rhodinized-carbon biosensor offers higher selectivity, greater linearity, lower sensitivity, and similar response time or short-term stability compared to the cupric-hexacyanoferrate enzyme electrode. Each of these catalytic transducers thus offer certain advantages, and accordingly may be more suitable for a particular biosensing application. Such assessment of the relative merits of electrocatalytic transducers should serve as a guide for designing ‘first-generation’ oxidase-based biosensors for specific applications.