Voltammetric determination of mifepristone at a DNA-modified carbon paste electrode.
A new strategy for the preparation of a DNA-modified carbon paste electrode is developed. It is found that the anodic response of mifepristone is greatly enhanced at the dsDNA-modified carbon paste electrode comparing with that obtained at the bare electrode, while the response at a ssDNA-modified electrode is similar to bare electrode. So the dsDNA-modified electrode is employed as a sensitive biosensor for the detection of mifepristone. A linear dependence of the peak currents on the concentration is observed in the range 2.0 x 10(-7) approximately 2.0 x 10(6) mol/L, with a detection limit of 1.0 x 10(-7) mol/L. The relative standard deviation is 4.3% for six successive determinations of 1.0 x 10(6) mol/L mifepristone. The determination of mifepristone tablets is carried out and satisfactory results are obtained.
Department of Chemistry, Nanjing University, PR China.
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K
Gu
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J
Zhu
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Zhu
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J
Xu
H Y
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Chen
D015374:Biosensing Techniques; D002244:Carbon; D003282:Contraceptives, Postcoital, Hormonal / Q000032:analysis*; D004247:DNA; D004563:Electrochemistry; D004566:Electrodes; D007202:Indicators and Reagents; D015735:Mifepristone / Q000032:analysis*
D003282:Contraceptives, Postcoital, Hormonal; D007202:Indicators and Reagents; D015735:Mifepristone; D002244:Carbon; D004247:DNA