A Novel Al3+-Selective Potentiometric Sensor Based on 3,4,13,14- Tetraphenyl-2,5,12,15-Tetraazatricyclo[11,0,0^611]cosa;1(16),2,4,7,9, 6(11),12,14,17,19-Decaene in a PVC Matrix and its Application in Analyzing Biological Fluids

A novel PVC membrane electrode for Al3+ ion based on 3,4,13,14-tetraphenyl-2,5,12,15- tetraazatricyclo[11,0,0^611]cosa;1(16),2,4,7,9,6(11),12,14,17,19-decaene as a suitable ionophore was prepared. The electrode exhibits a Nernstian response for Al3+ ion over a wide concentration range (4.0 x 10^–8 to 1.0 x 10^–1 M) with a slope of 19.58 ± 0.3 mV/decade. The limit of detection is 2.0 x 10^–8 M. The electrode has a response time of 10 s and a useful working pH range of 3-11. The proposed membrane sensor shows good discriminating abilities towards Al3+ ion with regard to several alkali, alkaline earth transition and heavy metal ions. It was successfully used in the determination of aluminum ion in biological fluids and as an indicator electrode in the potentiometric titration of Al3+ ion with EDTA.