TY - JOUR
T1 - A stable interface based on aryl diazonium salts/SWNTs modified gold electrodes for sensitive detection of hydrogen peroxide
AU - Guo, Wenqi
AU - Jiang, Fangfang
AU - Chu, Jiemei
AU - Song, Dandan
AU - Liu, Guozhen
PY - 2013
Y1 - 2013
N2 - A stable and sensitive hydrogen peroxide (H2O2) biosensor based on aryldiazonium salt and SWNTs modified gold electrodes is reported. SWNTs were covalently anchored to the mixed monolayer of phenyl and 4-aminophenyl in molar ratio of 1:1 through aryldiazonium salt reaction to form stable C-C bonding. PEG molecules were introduced to the interface to resist non-specific protein adsorption. Covalent attachment of HRP to SWNTs allowed direct electron transfer to the redox protein with a rate constant of 28.6 ± 1.9 s-1, indicating a specific interaction between SWNTs and HRP. The covalently attached SWNTs facilitate the electrical coupling between protein and electrodes. The covalently immobilized HRP retained its catalytic activity by the enzyme responding to the addition of H2O2. The SWNTs/PEG/HRP modified sensing interface can be used for the detection of H2O2 in the range of 0.01-24 μM with a detection limit of 10 nM. Comparing to the sensing system in which HRP was physically adsorbed on the interface without the assembly of PEG, the performance of the SWNTs/PEG/HRP sensing interface has been significantly improved. The so fabricated biosensor exhibited high sensitivity, good reproducibility, and long-term stability, and can be used for the detection of H2O 2 in real samples with good recovery.
AB - A stable and sensitive hydrogen peroxide (H2O2) biosensor based on aryldiazonium salt and SWNTs modified gold electrodes is reported. SWNTs were covalently anchored to the mixed monolayer of phenyl and 4-aminophenyl in molar ratio of 1:1 through aryldiazonium salt reaction to form stable C-C bonding. PEG molecules were introduced to the interface to resist non-specific protein adsorption. Covalent attachment of HRP to SWNTs allowed direct electron transfer to the redox protein with a rate constant of 28.6 ± 1.9 s-1, indicating a specific interaction between SWNTs and HRP. The covalently attached SWNTs facilitate the electrical coupling between protein and electrodes. The covalently immobilized HRP retained its catalytic activity by the enzyme responding to the addition of H2O2. The SWNTs/PEG/HRP modified sensing interface can be used for the detection of H2O2 in the range of 0.01-24 μM with a detection limit of 10 nM. Comparing to the sensing system in which HRP was physically adsorbed on the interface without the assembly of PEG, the performance of the SWNTs/PEG/HRP sensing interface has been significantly improved. The so fabricated biosensor exhibited high sensitivity, good reproducibility, and long-term stability, and can be used for the detection of H2O 2 in real samples with good recovery.
UR - http://www.scopus.com/inward/record.url?scp=84879466195&partnerID=8YFLogxK
U2 - 10.1016/j.jelechem.2013.05.028
DO - 10.1016/j.jelechem.2013.05.028
M3 - Article
AN - SCOPUS:84879466195
VL - 703
SP - 63
EP - 69
JO - Journal of Electroanalytical Chemistry
JF - Journal of Electroanalytical Chemistry
SN - 1572-6657
ER -