|
چکیده
|
A sensitive and selective procedure for the determination of silver(I) at p-isopropylcalix[6]arene modified carbon paste electrode has been developed. Silver(I) was accumulated in open-circuit design on the electrode surface via complex formation with the modifier at pH 9.00. After electrochemical reduction of silver(I), the anodic stripping wave of silver(0) appeared at ?0.04 V versus reference electrode on scanning the potential in the positive direction in 0.1 M H2SO4 ? 2.0 9 10-2 M KBr. The effects of various parameters such as preconcentration time, stripping medium, reduction potential, etc. were investigated. In the optimum condition, a linear calibration curve was obtained in the range of 5.0 9 10-8 M to 2 9 10-6 M with detection limit (3d) of 4.8 9 10-8 M. Many coexisting metal ions had little effect on the determination of silver(I). Also, the proposed method was applied to the determination of silver(I) in X-ray photographic film samples. The results were in good agreement with those obtained by atomic absorption spectroscopy (AAS).
|