Monitoring Single DNA Docking Site Activity with Sequential Modes of an Optoplasmonic Whispering-Gallery Mode...

Area of Science:

• Nanotechnology
• Biophysics
• Analytical Chemistry

Background:

• Single-molecule techniques offer high precision for studying sub-diffraction limit molecules.
• Optoplasmonic whispering gallery mode (WGM) sensing combines LSPR and WGM for label-free characterization, even at the single-ion level.
• Current methods face challenges in isolating individual binding sites on multiplexed sensors.

Purpose of the Study:

• To characterize distinct binding sites of DNA analyte molecules on an optoplasmonic WGM sensor.
• To differentiate transient interactions from permanent hybridization at specific docking sites.
• To advance the understanding of molecular interactions at the single-molecule level using advanced sensing techniques.

Main Methods:

• Utilized optoplasmonic WGM sensing technology.
• Analyzed DNA hybridization to docking strands on the sensor.
• Employed the ratio of resonance shifts between sequential polar WGM modes for characterization.

Main Results:

• Successfully characterized different binding sites of DNA analyte molecules.
• Identified specific docking sites exhibiting transient interactions.
• Confirmed permanent hybridization of complementary analyte strands at identified sites.

Conclusions:

• The developed method allows for the detailed characterization of individual binding events on optoplasmonic WGM sensors.
• This technique provides insights into the dynamics of molecular interactions, distinguishing transient from stable binding.
• Offers potential for enhanced single-molecule analysis and understanding complex biological processes.