Authors: Huajie Zhang Kangbing Wu
Publish Date: 2005/01/05
Volume: 149, Issue: 1-2, Pages: 73-78
Abstract
Adsorption stripping voltammetry a very sensitive electroanalytical method was employed to determine reserpine a kind of antihypertensive drug In 01 M phosphate buffer with a pH of 60 reserpine was accumulated at a multiwall carbon nanotubes MWNTmodified glassy carbon electrode GCE surface under the condition of opencircuit In the following anodic sweep from 020 to 100 V reserpine adsorbed at the MWNTmodified GCE surface was oxidized and yielded a sensitive oxidation peak at 064 V Due to its unique structure and extraordinary properties MWNT shows a ten times higher accumulation efficiency toward reserpine compared with a bare GCE Hence the amount of reserpine at the MWNTmodified GCE surface increases significantly and finally the oxidation peak current improves greatly The experimental conditions such as supporting electrolyte pH value the amount of MWNTDHP suspension accumulation time and scan rate were optimized for the measurement of reserpine and a sensitive electroanalytical method was proposed for reserpine determination The oxidation peak current varies linearly with the concentration of reserpine over the range of 2×10−8 to 1×10−5 M and the detection limit is 75×10−9 M after 4 min opencircuit accumulation The relative standard deviation at 1×10−6 M reserpine was about 47 n=7 indicating excellent reproducibility This new method was successfully demonstrated with reserpine injections and tablets
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