Electrochemical DNA Scaffold-Based Sensing Platform for Multiple Modes of Protein Assay and a Keypad Lock System

Abstract

Development of a flexible, easy-to-use, and well-controllable DNA-based sensing platform would provide enormous opportunities to boost molecular diagnosis and signal transduction or information processing. Herein, a duplex DNA scaffold containing a bulge was deployed for the fabrication of a simple and general DNA-based electrochemical sensing platform. It could be harnessed for different signal output behaviors (one signal-off and two signal-on modes) toward a single-step analysis of the target protein. The detection limit toward the target protein could reach about 0.1 nM. Also, it could be used as a streamlined electrochemical workflow for the successive monitoring of protein binding. Furthermore, such an electrochemical sensing platform could be explored for the operation of the concatenated AND logic gates as a molecular keypad lock system. The current sensing platform based on only one duplex DNA scaffold presented features such as simple biosensor design and fabrication, flexible operation for different signal outputs, sensitive and selective protein detection, and expandable logic operation. It thus would pave a broad road toward the development of high-performance biosensors or logic devices to be applied for molecular diagnosis or computing.

Programmable DNA Nanomachine Integrated with Electrochemically Controlled Atom Transfer Radical Polymerization for Antibody Detection at Picomolar Level

“…Upon plotting SWV current versus the logarithmic concentration of anti-Dig, a good linear dependence ( R 2 = 0.9935) was obtained from 5 pM to 200 nM (Figure B), and the regression equation was i = 29.77 + 2.581 lg c . A detection limit of 1.5 pM was obtained based on the equation: LOD = 3 S b / m ( S b : the standard deviation of the blank measurements, m : the slope of the calibration curve). ,, Such low detection limit may be ascribed to the proposed amplification strategy, which rendered the sensing system attractive potential for various antibody analyses in comparison with other reports. − Furthermore, the sensing electrode was used to test anti-Dig at 10 nM for four repetitive measurements, leading to a relative standard deviation (RSD) of 3.1%. This result confirmed the outstanding reproducibility of the method.…”

Highly Efficient Quadruped DNA Walker Guided by Ordered DNA Tracks for Rapid and Ultrasensitive Electrochemical Detection of miRNA-21

“…In the past few decades, researchers have designed many highly complicated and powerful DNA molecular machines that could implement specific functions on a nanoscale, for example, DNA robots, − DNA tweezers, − DNA walkers, − etc. Among the various kinds of molecular machines, the DNA walker, a novel dynamic nanomachine, − which could walk along designed DNA tracks to guarantee transport of cargoes with the help of driving forces (the driving forces including strand displacement reaction (SDR), protein enzyme/DNAzyme reaction, and environmental stimuli), has attracted more and more eyes to explore in sensing systems, , bioimaging, − molecular computing, cargo delivery, programmed synthesis, logic gates devices, and so on. However, the biosensors based on DNA walker still faced ongoing challenges.…”