Amineptine plastic membrane electrode based on its ion associate with tetraphenylborate and phosphomolybdic acid

New amineptine hydrochloride (Am-CI) ion-selective electrodes (conventional type) based on amineptinium-tetraphenylborate (I) and amineptinium-phospho molybdate (II) were prepared. The electrodes exhibited mean slopes of calib ration graphs of 57.9 mV and 53.8 mV per decade of (Am-Cl) concentration at 25 degrees C for electrodes (I) and (II), respectively. The electrodes can be used within the concentration range 3.16x10(-5)-10(-2) M (Am-Cl) at a p H range of 2.0-3.9 for both electrodes, The standard electrode potentials w ere determined at different temperatures and used to calculate the isotherm al coefficients of the electrodes, which were 0.00172 V degrees C-1 and 0.0 0091 V degrees C-1 for (I) and (II) electrodes, respectively. The electrode s showed a very good selectivity for (Am-CI) with respect to a number of in organic cations and sugars. The standard addition method is successfully ap plied to determine (Am-Cl) in purl solutions and in amineptine-containing t ablets.