Electrochemical DNA biosensor for the detection of Listeria monocytogenes with dendritic nanogold and electrochemical reduced graphene modified carbon ionic liquid electrode
Electrochemical DNA biosensor for the detection of Listeria monocytogenes with dendritic nanogold and electrochemical reduced graphene modified carbon ionic liquid electrode
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DOI：
10.1016/j.electacta.2012.07.133
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发表时间：
2012-12
影响因子：
6.6
通讯作者：
Wei Sun;Xiaowei Qi;Yuanyuan Zhang;Hairong Yang;Hongwei Gao;Ying Chen;Zhenfan Sun
中科院分区：
文献类型：
--
作者：
Wei Sun;Xiaowei Qi;Yuanyuan Zhang;Hairong Yang;Hongwei Gao;Ying Chen;Zhenfan Sun
A new electrochemical DNA biosensor was fabricated by using a dendritic gold nanoparticles and electrochemical reduced graphene (GR) composite modified carbon ionic liquid electrode (CILE) as the platform. Ionic liquid 1-butylpyridinium hexafluorophosphate was used as the binder for the preparation of CILE and GR film was further decorated on the CILE surface by electrochemical reduction. Then the dendritic nanogold was electrodeposited on the surface of GR/CILE to get a modified electrode as Au/GR/CILE, which was further used for the formation of mercaptoacetic acid self-assembling film. The amino modified ssDNA probe sequence was covalently linked with mercaptoacetic acid to get the ssDNA modified electrode for the further hybridization. Methylene blue (MB) was used as the electrochemical indicator for monitoring the hybridization reaction after hybridized with the target ssDNA. Under the optimal conditions the specific Listeria monocytogenes hly ssDNA sequences could be detected by measuring the differential pulse voltammetric responses of the accumulated MB molecules on dsDNA molecules. The linear concentration range was achieved from 1.0×10−12to 1.0×10−6mol/L with the detection limit as 2.9×10−13mol/L (3σ). This electrochemical DNA sensor exhibited excellent selectivity with the good discrimination ability of one-base and three-base mismatched ssDNA sequences. The polymerase chain reaction product of L. monocytogenes hly gene that extracted from deteriorated fish was successfully detected, which indicated that this electrochemical DNA sensor could be further used for the detection of specific ssDNA sequence in real biological samples.
