Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10560238 | Talanta | 2005 | 5 Pages |
Abstract
The voltammetric behaviour of chloroquine was investigated at carbon paste and dsDNA-modified carbon paste electrodes in different buffer systems over a wide pH range using cyclic and differential pulse voltammetry. Chloroquine was oxidized in the pH range 2.0-11.0 yielding one irreversible main oxidation peak. A second peak was also observed only in the pH range 5.0-7.0. The modification of the carbon paste surface with dsDNA allowed a preconcentration process to take place for chloroquine such that higher sensitivity was achieved as compared with the bare surface. The response was characterized with respect to solution pH, ionic strength, accumulation time and potential, chloroquine concentration, and other variables. Stripping voltammetric response showed a linear calibration curve in the range 1.0 à 10â7 to 1.0 à 10â5 mol lâ1 with a detection limit of 3.0 à 10â8 mol lâ1 at the dsDNA-modified electrode. Application of the modified electrode to serum, without sample pretreatment, resulted in good recovery higher than 95% and the higher standard deviation was 3.0%.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
A. Radi,