Plasmonic scattering imaging of single proteins and binding kinetics

Area of Science:

• Biophysics
• Analytical Chemistry
• Biotechnology

Background:

• Accurate measurement of single protein binding kinetics is crucial for understanding biological processes.
• Existing surface plasmon resonance (SPR) techniques lack the capability for single protein imaging.
• There is a need for advanced methods to analyze protein behavior at the single-molecule level.

Purpose of the Study:

• To develop and demonstrate a novel surface plasmon resonance (SPR) scattering technique for imaging single proteins.
• To enable label-free quantification of protein binding kinetics at the single-molecule level.
• To provide a new tool for analyzing protein heterogeneity and behavior in biological samples.

Main Methods:

• Utilizing surface plasmon resonance (SPR) scattering to image individual protein molecules.
• Developing methods to measure protein size and identify them via antibody binding.
• Quantifying binding kinetics by counting individual molecular binding events.

Main Results:

• Successfully imaged single proteins using SPR scattering, overcoming previous limitations.
• Demonstrated the ability to measure protein size and identify specific proteins.
• Established a digital method for quantifying protein binding kinetics and analyzing molecular behavior heterogeneity.

Conclusions:

• SPR scattering is a viable and powerful technique for single protein imaging and kinetic analysis.
• This method offers a sensitive, label-free approach for studying protein interactions.
• The technique holds significant promise for analyzing low-volume samples, including single cells.