“…A literature survey revealed that among the reported ISEs base on PVC membrane very little was published on trivalent ions, e.g., Au(III) [2,3], Bi(III) [4], Al (III) [5 ± 8] and Cr(III) [9 ± 16]. The reported chromium selective electrodes are based on Aliquate 336 S À Cr(SCN) 4 À ion pair [9], 8-quinoline-dithiocarboxilate [10], chromium dithizonate [11], (2,4,9,11-tetraphenyl-1,5,8,12-tetraazacyclotetradeca-1,4,8,11-tetraene dihydrogen perchlorate) [12], macrocyclic compound [13], 4-methylaminazobenzene [14], glyoxal bis (2-hydroxyanil) [15] and 2,3,8,9-tetraphenyl-1,4,7,10-tetraazacyclododeca-1,3,7aene [16].…”