Determination of ascorbic acid by polypyrrole potentiometric detector in ion chromatography.

A potentiometric detector, based on electrodeposition of polypyrrole onto Pt electrode, was investigated in this study. The chromatographic performance of the PPy detector was investigated in ion chromatography. The resulting PPy detector exhibited good performance for AA determination with a wide linear range (1.0 x 10(-6) to 1.0 x 10(-2)M), a highly reproducible response (R.S.D. of 2.45%), without any interference and long-term stability. The calculated detection limit was 7.0 x 10(-5)mM at 3 sigma. The calibration results showed good Nernstian behavior and also satisfactory low detection limit. In order to verify the reliability of the PPy detector, it was applied to the determination of AA in pharmaceutical samples. The results were satisfactory and agreed closely with the manufacturers' stated contents. The PPy electrode can be used as an alternative novel potentiometric detector material for determination of AA in standards and pharmaceutical samples.