Ion-selective optode membranes using 9-(4-diethylamino-2-octadecanoatestyryl)-acridine acidochromic dye Original Research Article

Ion-selective optode membranes incorporating calix[4]arene derivatives for cation recognition, and a lipophilic acidochromic dye for transduction have been prepared. The response of the resulting optode membranes has been measured over the range 400–800 nm. Comparisons are made between the analytical performance of a commercially available pH indicator (ETH 5294) and an alternative dye 9-(4-diethylamino-2-octadecanoatestyryl)-acridine with respect to dynamic range, selectivity and stability/lifetime. Kexch values and other membrane parameters have been estimated by means of fitting experimental data to theoretically derived equations.