Selective determination of dopamine in the presence of ascorbic acid at an over-oxidized poly(N-acetylaniline) electrode.
An over-oxidized poly(N-acetylaniline) (PNAANI)/GCE was used to determine dopamine (DA) in a large excess of ascorbic acid (AA) by differential pulse voltammetry. A linear relation between Ip and DA concentration was found over the range 5.0 x 10(-7) to 2.0 x 10(-5) M. The detection limit was 1.68 x 10(-8) M for S/N = 3 and 400 microM AA did not interfere with the DA determination. The high sensitivity was due to accumulation and selectivity was due to charge discrimination. The mechanism of selective determination of DA at over-oxidized PNAANI/GCE was also proposed.
Zheng
L
L
Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Wu
S
S
Lin
X
X
Nie
L
L
Rui
L
L
D001205:Ascorbic Acid; D004298:Dopamine / Q000032:analysis*; D004563:Electrochemistry; D004566:Electrodes
D001205:Ascorbic Acid; D004298:Dopamine