Preparation and measurement of combinatorial screen printed libraries for the electrochemical analysis of liquids.

A combinatorial approach to the development of new screen printing pastes is introduced. We used a novel technique for printing electrodes out of different binary mixtures of pastes. The pastes applied are based on the transition metals iridium and ruthenium in the form of their (IV) oxides. Using multielectrode arrays,these pastes were printed on the same substrate in one single step. In this work, pH sensors were printed based on a concept using solid state electrodes both with the measurement and the reference electrode.After the sintering process, the pastes were then evaluated using a robotic setup designed to handle the high impedances characteristic for pH sensors as well as to automatically manipulate the fluids in contact with the sensors.