Development of one electrode type pH sensor measuring in microscopic region

pH sensors are used to measure pH of solvents changed by a chemical reaction in a beaker. Those pH sensors are created by the glass electrode approach, which has a glass thin film of approximately 0.05 [mm] at the bottom, and source electrode, which has a liquid interchange at the bottom; in addition, a silver chloride electrode was included in each electrode. Because of the complex construction, the size increases, hence it is important to downsize the pH sensor in ex-change to monitor pH in microscopic measurement, for instance cells. Nonetheless, it is complicated to create a smaller sized in the glass electrode method; KCl solution is used as an internal liquid of the glass electrode and the source electrode. Hence, in this paper, the solid type of one electrode approach without an internal liquid as a new pH measuring method is proposed. An antimony electrode (as a working electrode) creates the one electrode approach and an Ag/AgIO 3 electrode (as a source electrode) deposited on the surface with Sb/Sb 2 O 3 and SiO 2 thin film (as an insulator) of the functioning electrode. Thus, the proposed sensor is a reliable sensor; therefore, the coefficient of determination between them shows more than 0.98.