Abstract
5,7,12,14-tetramethyldibenzo[b,i]-1,4,8,11-tetraazacyclotetradecane, Me(4)Bzo(2)[14]aneN(4). (I) was synthesized and used as an electroactive material for the fabrication of membrane electrode in PVC matrix for the determination of Cu2+. The best performance was given by the membranes of macrocycle (I) with composition 5:3:100:150 (I:NaTPB:DBBP:PVC). The sensor worked well over a concentration range 2.5 x 10(-5)-1.0 x 10(-1) M of Cu2+ with a slope of 30.2 +/- 0.3 mV (decade)(-1) of Cu2+ activity, a fast response time of 13 +/- 2 s and a lifetime of five months. The working pH range of this sensor is 2.6-5.5 and it shows excellent selectivity for Cu2+ over other mono-, di- and trivalent cations. Its performance in partially nonaqueous medium was found to be satisfactory. The sensor can also be used as an indicator electrode in the potentiometric titration of Cu2+ against EDTA and its determination in real samples.