Physical characterizations of a screen-printed electrode for use in an amperometric biosensor system

Screen-printed electrodes are widely used in modern biosensor applications. The conditions under which screen-printing takes place contribute to the electrical properties of the electrodes produced. This article describes a disposable carbon paste electrode that is used as the basis of an amperometric immunosensor incorporating the electroactive polymer polyaniline. The electrodes are manufactured using a semiautomated screen-printing system. The conditions used for the screen-printing of the carbon ink were investigated using physical methods such as scanning electron microscopy and cyclic voltammetry to establish how differences in the carbon surface translated into changes in the performance characteristics of the electrode. A process of electrochemical surface pretreatment was studied with a view to maximizing amperometric responses for subsequent enzyme and antibody-based biosensor applications. Comparisons between the screen-printed electrodes and glassy carbon electrodes are also made.