An unique DNA junction scaffold-based electrochemical sensing platform achieving multilevel signal responses for amplified multiplexed nucleic acid analysis and logic operation

Abstract

Herein, a DNA junction scaffold structure was exploited as the only immobilization probe to construct a simple and multifunctional electrochemical sensing platform. The programmable operation of a catalytic DNA circuit reaction on it afforded the amplified and well-controllable signal responses for the individual and simultaneous analysis of two nucleic acid targets. Also, it could be flexibly harnessed for each target assay based on multilevel signal response behaviours including single-signal, dual-signal and ratiometric signal responses. Then, its application for the operation of two logic devices of “AND” and “OR” gates toward different target inputs was demonstrated. Interestingly, the “OR” gate could be in-situ evolved from the “AND” status by simply controlling signal output. The low detection limit could reach 10 fM whether for the simultaneous or individual analysis of two targets in buffer or serum. Current sensing platform by only a DNA junction scaffold probe features in facile biosensor fabrication and operation, sensitive and selective analysis of multiplexed targets, well-controllable and multilevel signal response behaviours, and expandable logic operation. It thus may open a promising avenue toward the development of advanced biosensors or logic devices applied for molecular diagnosis or information processing.