Potentiometric properties of polypyrrole films doped with calmagite

Electrochemically deposited polypyrrole films doped with calmagite, a multi valent complexing ligand, has been studied. The films were deposited on a p latinum substrate by using cyclic voltammetry. Calmagite was incorporated i n the polymer matrix during polymerisation. Calmagite belongs to the group of metallochromic indicators and forms complexes with calcium, magnesium an d copper. By using calmagite as doping ion the sensitivity of the film towa rds these specific cations is enhanced. This was checked by measuring the p otentiometric response of the films. As the complexation between calmagite and the metal ions is pH dependent the proper pH range had to be used to ob tain good potentiometric response of the films. EDAX spectroscopy was used to get further information about the complexation.