Flow injection potentiometric determination of pipazethate hydrochloride

New plastic membrane electrodes for pipazethate hydrochloride based on pipa zethatium phosphotungstate, pipazethatium phosphomolybdate and a mixture of the two were prepared. The electrodes were fully characterized in terms of composition, life span, pH and temperature and were then applied to the po tentiometric determination of the pipazethate ion in its pure state and pha rmaceutical preparations under batch and flow injection conditions. The sel ectivity of the electrodes towards many inorganic cations, sugars and amino acids was also tested.