TY - JOUR
T1 - Selective detection of dopamine in urine with electrodes modified by gold nanodendrite and anionic self-assembled monolayer
AU - Tsai, Tien Chun
AU - Huang, Fei Ho
AU - Chen, Jia Jin Jason
N1 - Funding Information:
The authors acknowledge the Center for Micro/Nano Science and Technology, National Cheng Kung University, for assistance with SEM operation. We would also like to thank the National Health Research Institute of Taiwan for financially supporting this work under grant NHRI-EX101-10139EI .
PY - 2013
Y1 - 2013
N2 - The determination of dopamine (DA) in urine is a promising technique for non-invasive DA monitoring, but current electrochemical techniques face substantial interference from uric acid (UA). This study applies three-dimensional gold nanodendrite (Au-DT) and self-assembled monolayer (SAM) to modify gold electrodes to improve their sensitivity and specificity to DA and alleviate UA interference. With the optimal ω-mercaptoalkane carboxylic acid chain length, the differential pulse voltammograms of Au-DT deposited electrode coated with 8-mercaptooctanoic acid (MOA) exhibit two voltammetric peaks that represent the oxidation potentials of DA and UA, respectively, with a separation of 260 mV. Amperometric measurements show that the response current of Au-DT/MOA linearly depends on DA in the range of 0.01-5 μM. The sensitivity of the Au-DT/MOA modified electrode is 20-fold that of the MOA-coated electrode. The proposed electrode has a low detection limit of 20 nM for DA at a signal to noise ratio of 3 and resistance to UA interference, showing no response current with UA addition and no obvious decrease in the sensitivity of DA detection in the presence of UA. Moreover, the performances of the developed electrode, including sensitivity, recovery, and reproducibility, are validated for detecting DA in non-diluted human urine, with satisfactory results.
AB - The determination of dopamine (DA) in urine is a promising technique for non-invasive DA monitoring, but current electrochemical techniques face substantial interference from uric acid (UA). This study applies three-dimensional gold nanodendrite (Au-DT) and self-assembled monolayer (SAM) to modify gold electrodes to improve their sensitivity and specificity to DA and alleviate UA interference. With the optimal ω-mercaptoalkane carboxylic acid chain length, the differential pulse voltammograms of Au-DT deposited electrode coated with 8-mercaptooctanoic acid (MOA) exhibit two voltammetric peaks that represent the oxidation potentials of DA and UA, respectively, with a separation of 260 mV. Amperometric measurements show that the response current of Au-DT/MOA linearly depends on DA in the range of 0.01-5 μM. The sensitivity of the Au-DT/MOA modified electrode is 20-fold that of the MOA-coated electrode. The proposed electrode has a low detection limit of 20 nM for DA at a signal to noise ratio of 3 and resistance to UA interference, showing no response current with UA addition and no obvious decrease in the sensitivity of DA detection in the presence of UA. Moreover, the performances of the developed electrode, including sensitivity, recovery, and reproducibility, are validated for detecting DA in non-diluted human urine, with satisfactory results.
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U2 - 10.1016/j.snb.2013.01.081
DO - 10.1016/j.snb.2013.01.081
M3 - Article
AN - SCOPUS:84875165166
SN - 0925-4005
VL - 181
SP - 179
EP - 186
JO - Sensors and Actuators, B: Chemical
JF - Sensors and Actuators, B: Chemical
ER -