Folding-based electrochemical biosensors: the case for responsive nucleic acid architectures

Area of Science:

• Biomolecular recognition and sensor technology.
• Electrochemical biosensing platforms.
• DNA nanotechnology for molecular detection.

Background:

• Traditional biosensors struggle with signal transduction and interference in real-world samples.
• Existing methods like ELISA and Western blots are cumbersome and lab-bound.
• The need for reagentless, real-time analytical devices remains unmet for broad biosensor application.

Purpose of the Study:

• To develop a general solution for signal detection in biosensors.
• To create a new class of biosensors based on binding-induced DNA probe folding.
• To enable reagentless, real-time detection of diverse analytes with high sensitivity and selectivity.

Main Methods:

• Utilizing electrochemistry to monitor binding-induced changes in the rigidity of electrode-bound, redox-tagged DNA probes.
• Designing DNA probes that undergo a conformational "folding" change upon target binding.
• Site-specific attachment of DNA probes to interrogating electrodes for signal transduction.

Main Results:

• Developed folding-based biosensors capable of detecting proteins, nucleic acids, and small molecules.
• Achieved rapid response times (seconds to minutes) and high sensitivity (sub-picomolar to micromolar).
• Demonstrated selectivity in complex samples like blood and cell lysates, with >99% reusability.

Conclusions:

• Folding-based biosensors provide a robust solution for reagentless, real-time molecular detection.
• The electrochemical readout linked to DNA physics offers superior signal transduction and background suppression.
• These biosensors are suitable for on-chip applications in diagnostics, proteomics, and drug discovery.