title: Determination of trace thorium using catalytic-adsorptive stripping voltammetry of the thorium-cupferron complex.
abstract: A sensitive stripping voltammetric procedure for trace measurement of thorium, based on the catalytic-adsorptive peak of the thorium-cupferron complex, is reported. Optimal experimental conditions include the use of 1mM BES buffer solution (pH 5.5), containing 20muM cupferron, an accumulation potential of -0.80 V (vs. Ag/AgCl), and a differential pulse potential scan. The resulting stripping procedure offers improved sensitivity over a previous stripping scheme for thorium. The limit of detection after 5 min preconcentration is 50 ng/l. (2 x 10(-10)M), the response is linear up to 8 x 10(-8)M, and the relative standard deviation at the 2.1 x 10(-8)M level is 4.4%. Possible interferences are evaluated.
authors.affiliation: Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, U.S.A.
authors.forename: R
authors.initials: R
authors.lastname: Setiadji
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: G
authors.initials: G
authors.lastname: Santana-Rios