Document Type : Original Article
Department of Chemistry, Mulawarman University, Samarinda-Indonesia, Jl. Barong Tongkok No.4 Kampus Gn. Kelua Samarinda 75123, Indonesia
The research on the preparation and characterization of Pb2+ Ion Selective Electrode (ISE) using dithizone (DTZ) as ion carrier has been done. Membrane of ISE was made with the optimum composition with ratio of DTZ : PVC : DOP was 6 : 3 : 1. The membrane was doped using 1M Pb2+ solution within 7 days, and characterized using FT-IR to determine the shift of wave number from the spectrum of the group from membrane before and after doped. The results of characterization of FT-IR spectra of membrane after doped, shows that there is a shift of wave number from absorption spectra of secondary amine (N-H) group and absorption spectra of thiol (S-H) group didn’t appear. The result of characterization of Pb2+ ISE shows that ISE worked well with range concentration of 1×10-4 - 1×10-1 M, with Nernst slope was 29.5 mV/decade and the limit of detection was 1.5×10-4 M. The electrode worked optimally at pH 5, the response time was 9-48 seconds and can be used within 6 weeks. The presence of interfere ions, such as Ag+, Zn2+, Cu2+, Cd2+, Cl- and SO42- didn’t affect to the determination of Pb2+ ions in the samples.