Study on fabrication ion-selective membrane electrodes to improve electrochemical characteristics of electrodes for applied in water analysis

In this paper, we report the photolithography manufacturing of solid- ion selective membrane electrodes ammonium and nitrate in a cleanroom, using ammonium ionophore I (nonactin) and nitrate ionophore VI as starting materials. The developed probes are utilized with multipurpose electrochemical devices to potentiometrically monitor the concentration of ammonium and nitrate ions.       The research results showed that, S-ISM ammonium and nitrate can be used to measure ammonium and nitrate ions with high selectivity; it is also stable under research circumstances, with hardly any change in the OCP signals over time and a low limit of detection (LOD) of 2.0 ppm for NH4+ and 2.5 ppm for NO3-.