PolyA-Bridged Capture Probe Architecture Enables High-Efficiency DNA Hybridization for Multiplex Biosensing...

Area of Science:

• Electrochemistry
• Nanotechnology
• Molecular Biology

Background:

• Conventional biosensors suffer from limited DNA hybridization kinetics due to heterogeneous capture probe conformations.
• This limits the speed and practicality of electrochemical biosensors, especially in real-world samples.
• Interfacial regulation using DNA nanostructures can improve capture probe accessibility and activity.

Purpose of the Study:

• To introduce a simplified molecular regulatory structure, the probe-polyA-probe (PAP) and capture probe (CP) system, for enhanced biosensor performance.
• To demonstrate the structural linearization of capture probes via dual-terminal hybridization with PAP, forming a bridged CP (BCP).
• To evaluate the BCP biosensor's efficiency, sensitivity, and versatility for various applications.

Main Methods:

• Fabrication of a gold electrode surface with a probe-polyA-probe (PAP) sequence.
• Formation of a bridged capture probe (BCP) through dual-terminal hybridization of the capture probe with PAP.
• Characterization of BCP biosensor performance for DNA hybridization, microRNA detection, and Pb2+ sensing.

Main Results:

• The BCP strategy achieved structural linearization of the capture probe, enhancing steric accessibility and hybridization efficiency.
• The BCP biosensor enabled rapid and sensitive DNA hybridization detection from 1 fM to 1 nM.
• The platform demonstrated versatility, successfully constructing biosensors for microRNA and Pb2+ with rapid kinetics (3 min) and high efficiency (95.56%).

Conclusions:

• The BCP biosensor significantly enhances DNA hybridization kinetics and efficiency compared to conventional methods.
• The BCP strategy offers a versatile and robust platform for developing high-performance electrochemical biosensors.
• This approach holds promise for advancing molecular diagnostics and environmental monitoring applications.