Conductometric Determination of Some Important Carboxylic Acid Derivatives and Hydrochlorides in Pharmaceutical Formulations

A simple and sensitive electroanalytical method for determination of four compounds of pharmaceutical interest: flunarizine hydrochloride (F.HCl). ramipril (RAM). terbinafine hydrochloride (T.HCl). and tranexamic acid (TRA) has been developed. The method was based on the titration of these compounds either with sodium hydroxide or tetrabutylammonium hydroxide (TBA). Alternatively. silver nitrate was used for titration of flunarizine and terbinafine hydrochlorides. End point was detected conductometrically. The method allowed for determination of the studied drugs in the range 0.5-30 mg. Mean percentage recoveries ranged from (98.96 +/- 1.034) to ( 100.83 +/- 0.528). The proposed method was successfully applied to the determination of the studied compounds in dosage forms. The results were in good agreement with those obtained applying official or reference methods. The proposed method could be also applied to the simultaneous analysis of a mixture of ramipril and hydrochlorothiazide (HCT) in tablet dosage forms.