An All-solid-state Cd2+-selective electrode with a low detection limit

A new all-solid-state Cd2+-selective electrode with a low detection limit was prepared by using conjugated thiophene oligomer alpha-sexithiophene (alpha-6T) as solid contact deposited between an ionophore-doped poly(vinyl chloride) membrane and a gold disc substrate. The electrode exhibited a Nernstian response for Cd2+ ions over a wide concentration range of 10(-3)-10(-7) M with a detection limit as low as 1.3 x 10(-8) M. Results showed that the fabricated potentiometric sensor was suitable for use within the pH range of 2.0-9.0 and exhibited good reproducibility for long-term measurements. (C) 2011 Elsevier B.V. All rights reserved.