Preparation of liquid electrode based on Amiloride drug complex in PVC matrix membrane

Amiloride hydrochloride ion-selective electrodes were constructed in polymeric membrane by using PVC and based on the use of active ion-pair (Amiloride - phosphotungstate) and the other ion pair (Amiloride-tetraphenylborate) with the following plasticizers: Di-butyl phthalate (DBPH), Di-octylphthalate (DOP) and Tri-butyl phosphate (TBP). The properties of these electrodes were studied, including: slope, correlation coefficient, concentration range, detection limit and life time. These electrodes (A, B and C) based on the ion pair (Amiloride phosphotungstate)and (D, E and F) based on the ion pair (Amiloride-tetraphenylborate)and the plasticizers used DBPH, DOP and TBP respectively they gave approximately the same linear concentration range from (1x10-5to 1x10-2M. The slopes are (54.198, 52.759, 50.91, 49.007,48.508 and 48.501) mV/decade, and the limit of detection (6×10,7×10-6, 1.75×10-5, 7×10-6 and  1.5×10-5)M,  with the response time (10, 30,10, 12, 10 and 35) Sec. and the lifetime were about (45, 35, 30, 21, 15 and 10) days respectively. The working pH range found to be (1.9 –7.8) for the -7, 1.5×10-6 concentration of Amiloride solution 1 ×10-3 M by using electrode A AmiloPT+DBPH).Also the interferences were studied via selectivity against monovalent,divalent, trivalent ions and interference of the other type of diuretic drugs Hydrochlorothiazide.The separated solution method and fixed interfering mixed method were used to determine the selectivity coefficient K pot A,B .Electrode A (Amilo-PT+DBPH) was used to determ ine Amiloride in the pharmaceutical samples of Amiloride Maduratic tablets and Saluretic tablets. The analytical methods results showed to be simple, rapid and with a good accuracy by comparing it with UV-spectrophotometric method using F-test.