Solid-state potentiometric ion sensor base on crown-ether compounds

SUMMARY Solid-State Potentiometric Ion Sensor Base On Crown-Ether Compounds In this work,a novel absolutely solid-state contact PVC-membrane ion-selective electrodes were produced. For this by using crown-ether compounds (neutral ionophore) such as Ionophore 1; 4,4'-Bis[4"-phenoxy(15-crown-5)methyl]benzyl and Ionophore 2; 2,3-(4'-Aminobenzo)-8,9: 14, 1 5-dibenzo-7, 1 6-dithia- 1,4-dioxa- 1 0, 1 3-diazacyclooctadecane the electrodes were prepared. The potantiometric performance characteristics of the electrodes were investigated in a computerised measurement system.lt was concluded that the electrode prepared with ionophore 1 was especially selective towards K+ ion; the electrode prepared with ionophore 2 was selective towards H* ion; meaning it is a pH sensor; and selective towards Fe3+. While the electode prepared with ionophore 1 showes Nernst behaviour towards K+ solution (>55(±15) mV/per 10 times change), the response times are short (<10 s) and the life times are long (at least 1-2 months). All electrodes show linear behaviour towards main ion solution in the concentration interval 1.10"2-1.10"5 moLL"1. On the electrode prepared with ionophore 2 the potantial differences, which occurs for each Fe3+ solution containing a concentration differce of 10 units are around (58±30) mV.The response times are short (<15 s) and the life times are long (at least 1-2 months).The prepared electrodes show linear behaviour towards main ion solution in the concentration interval LlO^-l.lO"5 moLL"1. While the PVC-membrane ff^ selective electrode which was developed with ionophore 2 showes linear behaviour between pH 2-1 1,the potential diffence occurring for each ph difference is around (69±20) v.The response times are short (<10 s) and the life times are long (at least 1-2 months). The electrodes' selectivity coefficients relating to the ions which do interference besides the main ion were calculated with "separate solution method". Key words: Ion selective electrode, solid-state electrode, crown-ether, PVC-membrane electrode vn