Anal. Bioanal. Electrochem., Vol. 3, No. 6, 2011, 565 - 586 Full Paper Perchlorate Selective Membrane Electrode Based on Surfactant-Modified Zeolite Y Nanocluster Alireza Nezamzadeh-Ejhieh * and Atefeh Badri Department of Chemistry, Islamic Azad University, Shahreza Branch, P.O. Box 311-86145, Shahreza, Isfahan, Iran *Corresponding Author, Tel.: +98 321-3292515; Fax: +98 321-3291018 E-Mail: arnezamzadeh@iaush.ac.ir Received: 13 October 2011 / Accepted: 14 December 2011 / Published online: 30 December 2011 Abstract- Surfactant modified zeolite Y nano cluster was used to characterize its ability as an anion carrier in a PVC membrane electrode. The electrode showed excellent response characteristics to perchlorate anion. The electrode exhibited Nernstian response to ClO 4 − anion over a wide concentration range covering the range 1.2×10 -6 to 1.5×10 -1 M with low detection limit 5.7×10 −7 M and a slope of 59.6±0.8 mV per decade of perchlorate concentration. The electrode possess fast response time, reasonable reproducibility, appropriate lifetime and, most importantly, good selectivity toward ClO 4 − relative to a variety of other common anions. The electrode response to perchlorate remained constant in the temperature range of 20-45 o C and in the presence of 1.0×10 -4 –3.2×10 -3 M NaNO 3 . The potentiometric response of the electrodes is independent of the pH of test solution in the pH range of 2.1–10.8. The proposed sensors were used in potentiometric determination of perchlorate ions in river and tap waters . Key words- Perchlorate, Surfactant Modified Zeolite Y (SMZ), Nanocluster, Potentiometry, Ion Selective Membrane Electrode, Poly Vinyl Chloride (PVC) 1. INTRODUCTION Perchlorate anions may be found at high concentration (more than 1000 ppm) in surface and ground waters [1] due to disposal of perchlorate salts that are used in solid propellants, Analytical & Bioanalytical Electrochemistry © 2011 by CEE www.abechem.com