HydroFlex® as pH Meter

Since 2010 we develop a pH meter based on HydroFlex® in a collaboration with Kurt-Schwabe Institute for Measuring and Sensor Technology eV Meinsberg. Goal of developing is a single-rod measuring cell which is able to operate under conditions that are not accessible by other pH meters. Such conditions are given in applications of the food industry and the chemical industry.

ZIM-LogoMessaufbau Measurements with asymmetric two-rod measuring cells showed an excellent linearity for a wide range of pH values (see graph below). The presented measuring was done with an Ag/AgCl reference electrode made by Sensortechnik Meinsberg GmbH in different buffer solutions.

For pH values 14 -16 sodium hydroxide solution of adequate concentration was used, for pH 0 hydrochloric acid. One and the same HydroFlex® was used for all measurements and dipped directly into the different solutions.
It should be noted that HydroFlex® did not have to be calibrated.
First measurings with an asymmetric single-rod measuring cell (H2 - Ag/AgCl) also showed very promising results und represent a further milestone for our development of a symmetric H2-H2 single-rod measuring cell.

Diagramm pH-Messung