An enantioselective polyaniline-coated membrane electrode based on chiral salen Mn(iii) as chiral selector

Abstract

A novel ion-selective electrode for chiral determination of mandelic acid (MA) is constructed of a poly(vinyl chloride) (PVC) membrane doped with a chiral salen Mn(III) compound as chiral selector and coated with a chemically generated film of polyaniline (PANI). The developed sensor displays a linear response towards L-MA over a wide concentration range of 1.0 × 10⁻¹ to 1.0 × 10⁻⁶ M with Nernstian slope of 57.6 mV per decade and the detection limit of 2.1 × 10⁻⁷ M. Ascribed to the hydration of PANI, it demonstrates a better potentiometric characteristic (especially, linear range, detective limit, response time) in contrast to the uncoated membrane based sensor.