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Updated: Apr 21, 2026

Fabrication of Electrochemical-DNA Biosensors for the Reagentless Detection of Nucleic Acids, Proteins and Small Molecules
Published on: June 1, 2011
Direct detection of DNA below ppb level based on thionin-functionalized layered MoS2 electrochemical sensors
Tanyuan Wang1, Ruizhi Zhu, Junqiao Zhuo
1Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, P.R. China.
Abstract:
A layered MoS2-thionin composite was prepared by sonicating their mixture in an ionic liquid and gradient centrifugation. Because DNA is rarely present in single-stranded form, either naturally or after PCR amplification, the composite was used for fabrication of a double-stranded DNA (dsDNA) electrochemical biosensor due to stable electrochemical response, intercalation, and electrostatic interaction of thionin with DNA. The linear range over dsDNA concentration from 0.09 ng mL(-1) to 1.9 ng mL(-1) is obtained, and moreover, it is suitable for the detection of single-stranded DNA (ssDNA). The biosensor has been applied to the detection of circulating DNA from healthy human serum, and satisfactory results have been obtained. The constructed DNA electrochemical biosensor shows potential application in the fields of bioanalysis and clinic diagnosis. Furthermore, this work proposes a new method to construct electrochemical biosensors based on MoS2 sheets.

