Highly sensitive and selective dopamine biosensor based on a phenylethynyl ferrocene/graphene nanocomposite modified electrode.
A new ferrocene derivative (1-[(4-amino) phenylethynyl]ferrocene, Fc-NH(2)) was synthesized for the first time. The ferrocene derivative molecule contained the phenylethynyl skeleton, ferrocene and amino groups with excellent electrochemical properties. The graphene/Fc-NH(2) nanocomposite was prepared by mixing graphene solution and Fc-NH(2) solution in one pot and the nanocomposite was utilized to construct a Nafion/graphene/Fc-NH(2) modified glassy carbon electrode (GCE). The ferrocene derivative immobilized on the graphene can enhance the charge-transport ability of the nanocomposite, stabilize the graphene and prevent the leakage of ferrocene. The detection signal of dopamine (DA) was significantly amplified on the Nafion/graphene/Fc-NH(2)/GCE. It was experimentally demonstrated that the signal enhancement results from the synergy amplification effect of graphene and the Fc-NH(2). The oxidation peak currents of DA were linearly related to the concentrations in the range of 5 × 10(-8) to 2 × 10(-4) M with the detection limit of 20 nM in the absence of uric acid (UA) and ascorbic acid (AA). In the presence of 10(-3) M AA and 10(-4) M UA, the linear response range was 1 × 10(-7) to 4 × 10(-4) M, and the detection limit was 50 nM at S/N = 3. Using the proposed Nafion/Fc-NH(2)/graphene/GCE, DA was successfully determined in real samples with the standard addition method.
Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education, China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China. liu_meiling@126.com
Meiling
M
Liu
Linping
L
Wang
Jianhui
J
Deng
Qiong
Q
Chen
Yuzhen
Y
Li
Youyu
Y
Zhang
Haitao
H
Li
Shouzhuo
S
Yao
D001205:Ascorbic Acid / Q000737:chemistry; D015374:Biosensing Techniques; D004298:Dopamine / Q000032:analysis*; D055664:Electrochemical Techniques; D004566:Electrodes; D005296:Ferrous Compounds / Q000737:chemistry*; D005465:Fluorocarbon Polymers / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D000075163:Metallocenes; D053761:Nanocomposites / Q000737:chemistry*; D010084:Oxidation-Reduction; D014527:Uric Acid / Q000737:chemistry
D005296:Ferrous Compounds; D005465:Fluorocarbon Polymers; D000075163:Metallocenes; D014527:Uric Acid; C040402:perfluorosulfonic acid; D006108:Graphite; D001205:Ascorbic Acid; C004998:ferrocene; D004298:Dopamine