Analytical Sciences

Abstract − Analytical Sciences, 33(5), 585 (2017).

A Novel Electrochemical Sensor Based on [Ru(NH3)6]Cl3 as a Redox Indicator for the Detection of G-G Mismatched DNA
Xiaoqian ZHU,* Min HUANG,* Jiao LI,* Hanping HE,*,** Xiuhua ZHANG,*,** and Shengfu WANG*,**
*Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Youyi Road 368, Wuchang, Wuhan, Hubei 430062, P. R. China
**Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Hubei University, Youyi Road 368, Wuchang, Wuhan, Hubei 430062, P. R. China
In this paper, a novel electrochemical sensor was developed for the rapid detection of G-G mismatched DNA based on hexaammineruthenium(III) chloride ([Ru(NH3)6]Cl3) as a redox indicator. The sensor platform was constructed by immobilizing small molecules (NC-linker) on the gold electrode via amide bonds. The as-prepared NC-linker as the nucleic acids recognition molecule can interact with the G base of DNA. After the sensor was incubated with G-G mismatched DNA, the double-stranded DNA (dsDNA) acted as carriers of the signal tags-[Ru(NH3)6]Cl3, which resulted in a remarkable electrochemical signal. More binding of [Ru(NH3)6]Cl3 led to increases of the electrochemical signal. Other mismatched DNA produced only a low response, as well as complementary DNA. Thus G-G mismatched DNA can be easily discriminated from other mismatched and complementary DNA based on the sensor. Furthermore, the method was simple, rapid and repeatable for the detection of G-G mismatched DNA. The selective detection of target dsDNA was achieved by a relative current ratio of the target and control DNA. These results demonstrated that this strategy could provide great promise for the rapid and specific detection of other sequence-specific DNA.