Multifunctional DNA scaffold mediated gap plasmon resonance: Application to sensitive PD-L1 sensor

Area of Science:

• Plasmonics
• Nanotechnology
• Biosensing

Background:

• Noble metal nanoparticles improve Surface Plasmon Resonance (SPR) sensitivity through resonance coupling.
• Gap structure design is crucial for optimizing plasmon resonance and optical properties in nanoparticle systems.
• Nucleic acid nanostructures offer stability, flexibility, and biocompatibility for gap construction, while 2D MOFs provide a stable substrate.

Purpose of the Study:

• To develop a novel nano gap structure for enhanced SPR sensing using nucleic acid nanostructures and 2D metal-organic frameworks (MOFs).
• To investigate the potential of DNA nanostructures and Cu-Tcpp MOF for creating precisely controlled gap coupling plasmon systems.
• To improve the sensitivity and electric field enhancement of SPR chips.

Main Methods:

• Fabrication of a nano gap structure integrating Cu-Tcpp MOF film and DNA tetrahedron immobilization between a gold film and gold nanorods.
• Utilizing the rigidity and programmability of DNA tetrahedrons to control gap size and flexibility.
• Employing Finite-Difference Time-Domain (FDTD) simulations and experimental validation.

Main Results:

• Successfully constructed a nano gap with a porous scaffold structure using DNA tetrahedrons and Cu-Tcpp.
• Demonstrated precise control over the gap size and enhanced flexibility of the coupling structure through DNA design.
• Observed significant enhancement in electric field strength near the chip surface and improved SPR sensitivity.

Conclusions:

• The integration of DNA nanostructures and 2D MOFs offers a promising approach for advanced SPR chip design.
• DNA nanostructures are effective in precisely controlling nano gap dimensions for plasmonic applications.
• This research highlights the significant potential of nucleic acid nanomaterials in developing next-generation SPR sensing platforms.