Long-range surface plasmon resonance imaging for bioaffinity sensors.

Area of Science:

• Biophysics
• Nanoscience
• Analytical Chemistry

Background:

• Surface plasmon resonance (SPR) imaging is a powerful technique for label-free detection of biomolecular interactions.
• Conventional SPR suffers from limited propagation length and electric field strength, affecting sensitivity.
• Developing enhanced SPR methods is crucial for advancing bioanalytical detection capabilities.

Purpose of the Study:

• To report a novel bioaffinity sensor utilizing long-range surface plasmon resonance (LRSPR) imaging.
• To demonstrate the enhanced detection capabilities of LRSPR imaging for surface binding interactions.
• To introduce a new fabrication technology for LRSPR multilayers suitable for biosensing.

Main Methods:

• Fabrication of a multilayered structure (SF10 prism/Cytop/gold/water) to support LRSPs at the water-metal interface.
• Utilizing Cytop, an amorphous fluoropolymer with a refractive index close to water, for dielectric symmetry.
• Performing LRSPR imaging experiments at a fixed incident angle to monitor surface binding events.

Main Results:

• LRSPs exhibit longer propagation lengths, higher electric field strengths, and sharper resonance curves compared to conventional surface plasmons.
• LRSPR imaging demonstrated an enhanced response for detecting surface binding interactions.
• Successful monitoring of 16-mer single-stranded DNA (ssDNA) hybridization adsorption onto an ssDNA array using LRSPR imaging.

Conclusions:

• The developed LRSPR imaging sensor offers enhanced sensitivity for detecting biomolecular interactions.
• The novel fabrication technology is suitable for creating ssDNA arrays on LRSPR multilayers.
• LRSPR imaging presents a promising advancement for sensitive bioaffinity sensing applications.