Rubidium ion-selective electrodes based on indanopyrazolo[1,5-a]pyrimidines

Abstract

Rubidium ion-selective PVC membrane electrodes based on indanopyrazolo[1,5-a]pyrimidines as a novel class of neutral carriers were prepared. The electrode based on indano-3-amino-4-p-chlorophenylazopyrazolo[1,5-a]pyrimidine containing potassium tetrakis(4-chlorophenyl)borate as lipophilic salt and 2-nitrophenyl octyl ether as plasticizer gave the best performance. The electrode function was linear within the activity range 10^–1–10^–4 mol l^–1 and the Nernstian slope was 59 mV decade^–1. The selectivity and response time of the electrode were investigated and it was found that the electrode exhibits good selectivity towards rubidium with respect to alkali, alkaline earth and some other metal ions. The electrode response and selectivity remained almost unchanged for at least 1 month. The effects of the internal solution concentration and pH on the potential response of the electrode were also studied.