In this project new architectures for sensors and/or biosensors will be developed. For this purpose, glassy carbon electrodes will be modified with carbon black within chitosan film. The electrochemical characteristics of the sensors will be evaluated by electrochemical techniques, namely: cyclic voltammetry, amperometry and electrochemical impedance spectroscopy. Such modifications are intended to significantly improve the properties of electrochemical sensors, improving the electrochemical response in terms of reduction of overpotential, potential interference from electroactive species, thereby increasing its selectivity. Furthermore, an increase of current intensity (increasing of analytical signal) and/or increase of sensitivity (increase of slope of the calibration curve) could be obtained. Potassium hexacyanoferrate (III) will be used as an electrochemical probe to evaluate the electrochemical properties of the modified carbon electrodes, being determined and compared the electroactive area, the coverage area and the heterogeneous electron transfer constants. The sensor which present a better performance will be applied in the determinations of analyses of interest such as pharmaceutical products and biological fluids. Moreover, the performance of these electrodes in terms of linear response range (analytical curve), limits of detection and quantitation, sensitivity, potential interferences and lifetime will be evaluated.
News published in Agência FAPESP Newsletter about the scholarship: