Electrochemical Biosensor for Multiplexed Detection of Nucleic Acids Using a DNA Three-Way Junction with Metal Ion Intercalation

The multiplexed detection ability of biosensors can improve the accuracy of the early-stage disease diagnosis. Besides, an electrochemical technique is particularly well-suited for enabling such multiplexed target detection. The DNA three-way junction (3WJ) structure is capable of multiplexed detection of nucleic acids accompanying enhanced stability compared to a conventional double-stranded DNA structure. However, the introduction of redox active molecules for demonstration of electrochemical biosensing should be addressed for simple detection. In this study, we propose an electrochemical biosensor based on the 3WJ-<u>m</u>etal ion <u>i</u>ntercalated <u>D</u>NA (3WJ-MID) for simultaneous detection of multiple DNA targets. To amplify the electrochemical response, an <u>el</u>ectrode with <u>A</u>u <u>n</u>anopatterns is employed as an electrode. As targets of this biosensor, human papillomavirus type 16 and 18 DNAs are detected for validation of multiplexed target detection. We expect that this biosensor can be used for the multiplexed detection of various nucleic acid biomarkers, including viral DNAs.