ABSTRACT
With the aid of the analytical energy dispersive X-ray fluorescence technique with radioisotope excitation, the concentrations of metals in commercial tablets containing 0.25 mg of digoxin were estimated. Concentrations ranging from 2.99 to 10.70 µg of Fe; 1.59 to 2.30 µg of Ni; 0.94 to 5.48 µg of Cu and 0.11 to 5.72 µg of Zn were found per tablet analyzed. The experimental detection limits for these elements varied from 13.03 to 22.57 µg l−1, while the relative errors made in the quantification of these metals were lower than 15%.
ACKNOWLEDGMENTS
The authors are grateful to Fundação de Apoio à Pesquisa do Estado de São Paulo (FAPESP) and Conselho Nacional de Desenvolvimento Científico e Tecnológico-Programa Institucional de Bolsas de Iniciação Científica (CNPq-PIBIC) for financial support and fellowship given to the last author.