Using the voltammetric senor which is constracted inrnour laboratory and the membrane stabilized interface betweenrntwo immiscible electrolyte solution in a flow injectionrnsystem the transfer of anions (CIO ,NO & 01 land catiol'srn4 '3rn+ +rn(i( Na lfrom the aqueous to the organic phase have beenrninvestiJ'(ated.ln order to determine the Horking potentialrnregion of the system the behaviour of the potential-currentrndependence of the support inA electrolytes Here studied. TherniR drop resulting fron the dilution effect of tl,e distilledrnIvate'!, at the interface has been investigated and it Hasrncompensated by increasing 1;he concentration of thernsupporting electrolyte in t,he aqueous phase . Dependence ofrnthe peak current on the appliedrnconcentration of various ions (ClO ,rn4rnbeen investigat,ed. The det,erminationrnpotentialsrn_. + +rnNO , K & Narn3rnof K+ and Na+rnin the presence of dibenzo-18-croHn-6 in thernand onrnhavernHas madernorganicrn+rnphase. The method "as applyed to t),e determination of Na andrn+ K in blood serum samples Hnd the values obtained Vere inrngood agreement Iii th the values obtained by flame photometricrnmethod. The selectivity of the method Has also studied andrnlias found to be potential dependent and governed bv thernpartial sensitivity of the individual ion. A method has alsornbeen proposed for the deternd ngtion of a particu} ar ion inrnthe presence of another ion. The detection limit of therndetector has heen determined to be about 0.25 ÂµM forrnperchlorate ion. Thus the method is rapid, precise,rnsensitive for the determination of some anions and cations.