TY - JOUR
T1 - Simultaneous voltammetric detection of dopamine and uric acid at their physiological level in the presence of ascorbic acid using poly(acrylic acid)-multiwalled carbon-nanotube composite-covered glassy-carbon electrode
AU - Liu, Aihua
AU - Honma, Itaru
AU - Zhou, Haoshen
N1 - Funding Information:
A. Liu and HS. Zhou would like to thank the Japan Society for the Promotion of Science (JSPS) for the financial support of this work.
PY - 2007/8/30
Y1 - 2007/8/30
N2 - The use of poly(acrylic acid) (PAA)-multiwalled carbon-nanotubes (MWNTs) composite-coated glassy-carbon disk electrode (GCE) (PAA-MWNTs/GCE) for the simultaneous determination of physiological level dopamine (DA) and uric acid (UA) in the presence of an excess of ascorbic acid (AA) in a pH 7.4 phosphate-buffered solution was proposed. PAA-MWNTs composite was prepared by mixing of MWNTs powder into 1 mg/ml PAA aqueous solution under sonication. GCE surface was modified with PAA-MWNTs film by casting. AA demonstrates no voltammetric peak at PAA-MWNTs/GCE. The PAA-MWNTs composite is of a high surface area and of affinity for DA and UA adsorption. DA exhibits greatly improved electron-transfer rate and is electro-catalyzed at PAA-MWNTs/GCE. Moreover, the electro-catalytic oxidation of UA at PAA-MWNTs/GCE is observed, which makes it possible to detect lower level UA. Therefore, the enhanced electrocatalytic currents for DA and UA were observed. The anodic peak currents at ∼0.18 V and 0.35 V increase with the increasing concentrations of DA and UA, respectively, which correspond to the voltammetric peaks of DA and UA, respectively. The linear ranges are 40 nM to 3 μM DA and 0.3 μM to 10 μM UA in the presence of 0.3 mM AA. The lowest detection limits (S/N = 3) were 20 nM DA and 110 nM UA.
AB - The use of poly(acrylic acid) (PAA)-multiwalled carbon-nanotubes (MWNTs) composite-coated glassy-carbon disk electrode (GCE) (PAA-MWNTs/GCE) for the simultaneous determination of physiological level dopamine (DA) and uric acid (UA) in the presence of an excess of ascorbic acid (AA) in a pH 7.4 phosphate-buffered solution was proposed. PAA-MWNTs composite was prepared by mixing of MWNTs powder into 1 mg/ml PAA aqueous solution under sonication. GCE surface was modified with PAA-MWNTs film by casting. AA demonstrates no voltammetric peak at PAA-MWNTs/GCE. The PAA-MWNTs composite is of a high surface area and of affinity for DA and UA adsorption. DA exhibits greatly improved electron-transfer rate and is electro-catalyzed at PAA-MWNTs/GCE. Moreover, the electro-catalytic oxidation of UA at PAA-MWNTs/GCE is observed, which makes it possible to detect lower level UA. Therefore, the enhanced electrocatalytic currents for DA and UA were observed. The anodic peak currents at ∼0.18 V and 0.35 V increase with the increasing concentrations of DA and UA, respectively, which correspond to the voltammetric peaks of DA and UA, respectively. The linear ranges are 40 nM to 3 μM DA and 0.3 μM to 10 μM UA in the presence of 0.3 mM AA. The lowest detection limits (S/N = 3) were 20 nM DA and 110 nM UA.
KW - Ascorbic acid
KW - Dopamine
KW - Poly(acrylic acid)-multiwalled carbon-nanotubes composite
KW - Simultaneous determination
KW - Uric acid
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U2 - 10.1016/j.bios.2007.03.019
DO - 10.1016/j.bios.2007.03.019
M3 - Article
C2 - 17467972
AN - SCOPUS:34548511372
SN - 0956-5663
VL - 23
SP - 74
EP - 80
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
IS - 1
ER -