Voltammetric Study of the Complexation of Propafenone Hydrochloride (Rythmol Sr) With Co2+, Ni2+, Zn2+, and Mn2+ Ions

Abstract

Square-wave (SW) voltammetric investigation of the binding processes of propafenone hydrochlo-ride (PFOH) with Co2+, Ni2+, Zn2+, and Mn2+ ions was carried out at pH of 7.4. For the formed complexes, both average stoichiometries and stability constants were found by means of modified De Ford-Humemethod. According to SW voltammetric data, the metal : ligand ratio of 1 : 2 for Mn2+ was obtained. More-over, PFOH formed complexes in average metal : ligand ratio of 1 : 2 for Ni2+ and Zn2+; however, this averageratio was 1 : 6 for the Co2+ complex in the solution phase. The order of their stability constants was observed to obey Co(PFOH)(6) >> Ni(PFOH)(2) > Zn(PFOH)(2) > Mn(PFOH)(2). Also, the ligand numbers and formation constants of the successively formed Co(PFOH)(j), Ni(PFOH)(j), and Zn(PFOH)(j) complexes in solution phase were calculated.