Electrochemical DNA Sensor Based on Chitosan-Graphene and Electrodeposited Gold Nanoparticle Modified Electrode for the Detection of Staphylococcus aureus nuc Gene Sequence

Title:Electrochemical DNA Sensor Based on Chitosan-Graphene and Electrodeposited Gold Nanoparticle Modified Electrode for the Detection of Staphylococcus aureus nuc Gene Sequence

Volume: 14 Issue: 2

Author(s): Xueliang Niu, Wen Zheng, Xiaoyan Li, Wenshu Zhao, Zuorui Wen, Qiutong Li, Hui Xie and Wei Sun*

Affiliation:

• Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158,China

Keywords: Graphene, Gold nanoparticle, Electrochemical DNA sensor, Staphylococcus aureus nuc gene, Carbon ionic liquid electrode, chitosan-graphene (CTS-GR).

Abstract: Background: Electrochemical DNA sensor is a convenient and sensitive method for the detection of target ssDNA sequence. The developments of nanomaterials modified electrodes provide more opportunity for the enhancement of the analytical performances.

Objective: The aim of this paper is to construct a new electrochemical DNA sensor for the detection of Staphylococcus aureus nuc gene sequence with a chitosan-graphene (CTS-GR) and gold nanoparticles (AuNPs) modified electrode.

Methods: Electrodeposition was used to synthesize AuNPs directly on carbon ionic liquid electrode (CILE) to obtain AuNPs/CILE. Then CTS-GR nanocomposite was dropped on the surface of AuNPs/CILE to obtain CTS-GR/AuNPs/CILE. The nanocomposite on the electrode was suitable for immobilization of probe ssDNA sequence with electrostatic attraction. Hybridization took place with the complementary ssDNA sequences and assessed with methylene blue (MB) as electrochemical indicator.

Results: Due to the synergistic effects of CTS-GR and AuNPs, the modified electrode exhibited excellent electrochemical performances. The reduction peak currents of MB were in line with the concentration of the specific nuc gene sequences from 1.0×10-13 to 1.0×10-6 mol L-1 with a detection limit of 3.33×10-14 mol L-1 (3δ). This electrochemical DNA sensor displayed prominent selectivity to distinct different mismatched ssDNA sequences.

Conclusion: This electrochemical DNA biosensor exhibited properties such as higher sensitivity, wider linear range and lower detection limit, which were further applied to the PCR product detection with favorable results.

Cite this article as:

Niu Xueliang , Zheng Wen , Li Xiaoyan , Zhao Wenshu , Wen Zuorui , Li Qiutong , Xie Hui and Sun Wei *, Electrochemical DNA Sensor Based on Chitosan-Graphene and Electrodeposited Gold Nanoparticle Modified Electrode for the Detection of Staphylococcus aureus nuc Gene Sequence, Current Analytical Chemistry 2018; 14 (2) . https://dx.doi.org/10.2174/1573411013666170607123122