Abstract
An electrochemical stripping procedure for trace measurements of thymine is described by adsorption on a static mercury drop electrode. Cyclic voltammetry was used to characterize the interfacial and redox behavior. Optimum experimental conditions were found to be the use of a 0.005M NaOH solution, an initial potential of −0.08 V, a scan rate of 100 mV.s−1 and a linear scan mode. The response of free thymine is linear over the concentration range 0.1–0.5 ppm. Linear scan voltammetry, without acumulation time yields a detection limit of 62 ppb thymine. Acridine orange and copper were also investigated for measuring thymine in the presence of guanine.
ACKNOWLEDGMENTS
The authors gratefully acknowledge the CNPq and CAPES of the Government of Brazil for supporting of this work. The experimental assistance of A.B. Neves is appreciated.