Desenvolvimento de tintas condutivas e sua aplicação em eletrodos impressos

Abstract

The present work aimed the production of printed electrodes with potential applications in biosensors. This production was performed from raw materials required for the printing device. It was used as the electrode printing system screen printing method, which shows one of the best to conduct the process, as well as directed to the production of screen printing inks suitable for the formation of electrodes for electrochemical determination printed species. We identified the need to produce three inks for the preparation of the device: as silver ink conductive substrate, carbon working electrode and counter electrode, and silver-silver chloride electrode as a pseudo-reference. The silver paint was produced from the reduction of silver nitrate with hydrazine and the obtained powder was processed to obtain a flake, as it is the most suitable to produce the ink. The structure of silver is critical to obtaining an ink which has high conductivity. It was produced three types of paints. A carbon ink was prepared by incorporating graphite powder to a solution of resin copolymers of vinyl acetate / vinyl chloride. This formulation was used in the working electrode and counter-electrode. Another formulation was prepared similarly by changing appropriate amounts of silver flakes by silver chloride, forming the pseudo-reference electrode. We analyzed the purity of the precursors of the inks conductivity and electrochemical behavior front of a ferrocyanide redox pair as conventional ferrocyanide (II) / (III), and was observed good nearby systems. The cost of the described material is less than 50% of commercially available material, as well as its advantages. The experiment was prepared in order that, if necessary, to have the possibility of production of material on a pilot scale (pilot plant).