Screen-Printed Disposable Reference Electrodes

Abstract

In recent years there has been a pronounced interest in miniaturized, disposable electrochemical systems dedicated for electrochemical analysis. One of the most attractive approaches to yield such sensors (judging on the number of papers published) is screen printing of single electrodes or electrodes sets in various arrangements (i.e., combining all three electrodes required for classical electrochemical cell). Screen printing apart from miniaturization allows efficient large-scale production of sensors of relatively low cost and high reproducibility, which are of special interest for simple, fast electrochemical (both potentiometric and amperometric) determination of a range of analytes. Moreover, screen-printed electrodes can be obtained on a variety of substrates, although in practice the preference is given to synthetic polymeric materials (plastic foil). One of the big advantages of application of screen-printing technology is the possibility of developing own designs of electrodes and electrodes setups—even commercial, specialized suppliers of screen-printed electrodes usually allow custom designs. Moreover, the sequential printing of different layers, using different formulation of pastes, is especially suited for making miniaturized setups containing electrodes of different functions to be printed on one piece of support, e.g., reference, working (optionally modified with sensing layer), and counter electrodes. Screen-printing pastes in current use most often are designed to be cured at relatively low temperatures (compared to those used initially).