Refresh-In-Sensing Reusable Biosensor for Ultrasensitive Analysis of MicroRNA Based on Photoresponsive Plasmonic...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Molecular Biology

Background:

• MicroRNA detection is crucial for diagnostics and understanding biological processes.
• Plasmonic nanomaterials offer potential for sensitive optical sensing of molecules.
• Stable reusability of nanobiosensing platforms remains a significant challenge for practical applications.

Purpose of the Study:

• To develop a reusable plasmonic nanobiosensor for sensitive and cyclic detection of microRNA-21.
• To utilize photoresponsive DNA conformational switching for controlled sensing.
• To address the challenge of stable reusability in nanobiosensing platforms.

Main Methods:

• Integration of a single gold-silver core-shell nanocube (Au@Ag NC) with azobenzene-functionalized tetrahedron-structured DNA (tsDNA).
• Cyclic detection of microRNA-21 (miRNA-21) using photoresponsive conformational switching induced by alternating UV and visible light.
• Measurement of local surface plasmon resonance (LSPR) spectra for signal transduction.

Main Results:

• The developed nanobiosensor achieved cyclic detection of miRNA-21.
• A wide dynamic response range from 1 fM to 100 nM for miRNA-21 was observed.
• The platform demonstrated stable photoresponsive reusability.

Conclusions:

• The integrated Au@Ag NC and tsDNA nanobiosensor enables ultrasensitive and reusable detection of miRNA-21.
• Photoresponsive conformational switching provides a robust mechanism for cyclic sensing.
• The platform shows significant clinical potential for accurate miRNA detection.