A third-generation hydrogen peroxide biosensor based on horseradish peroxidase immobilized on DNA functionalized carbon nanotubes.
In this paper, DNA functionalized SWCNTs were used to immobilize horseradish peroxidase (HRP) on glassy carbon (GC) electrode. Cyclic voltammetry showed that the direct electrochemistry of HRP immobilized on DNA-SWCNTs hybrids was achieved. The DNA interlayer between the SWCNTs and HRP could be used to keep the activity of HRP. Compared with HRP-SWCNTs/GC and HRP-DNA/GC electrodes, the prepared HRP-DNA-SWCNTs/GC electrode exhibited more excellent electrochemical properties. Thus, the prepared HRP-DNA-SWCNTs/GC electrode was proposed as a third-generation H(2)O(2) biosensor. The effect of pH and applied potential on the performance of the biosensor was discussed in detail. Under the optimal conditions, a wide linear range of the propose biosensor for the detection of H(2)O(2) was observed from 6.0x10(-7) to 1.8 x10(-3)M. The detection limit was found to be 3.0 x10(-7)M at a signal-to-noise ratio of 3. Furthermore, the proposed biosensor displayed rapid response, high stability, very good reproducibility and high sensitivity for the detection of H(2)O(2). Determination H(2)O(2) concentration in disinfector sample by the proposed biosensor also showed satisfactory result.
Zeng
Xiandong
X
Hunan University, Changsha 410082, People's Republic of China.
Li
Xuefang
X
Liu
Xiaoying
X
Liu
Yong
Y
Luo
Shenglian
S
Kong
Bo
B
Yang
Shanli
S
Wei
Wanzhi
W
D015374:Biosensing Techniques / Q000295:instrumentation*; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry / Q000295:instrumentation*; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006735:Horseradish Peroxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure
D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D004247:DNA; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase