The spectrophotometric behavior of uranium (VI) with L-3-(3, 4-dihydroxy phenyl) alanine (LDOPA) reagent revealed that the uranium can form a ML2 complex with LDOPA in solution. Thus a highly sensitive adsorptive stripping voltammetric protocol for measuring of trace uranium, in which the preconcentration was achieved by adsorption of the uranium-LDOPA complex at hanging mercury drop electrode (HMDE), is described. Optimal conditions were found to be a 0.02M ammonium buffer (pH 9.5) containing 2.0105M (LDOPA), an accumulation potential of 0.1V (versus Ag=AgCl) and an accumulation time of 120 sec. The peak current and concentration of uranium accorded with linear relationship in the range of 0.5–300 ng ml1. The relative standard deviation (at 10 ng ml1) is 3.6% and the detection limit is 0.27 ng ml1. The interference of some common ions was studied. Applicability to different real samples is illustrated. The attractive behavior of this reagent holds great promise for routine environmental and industrial monitoring of uranium.
