Light scattering methods for tracking gold nanoparticles aggregation induced by biotin-neutravidin interaction

Area of Science:

• Nanoparticle characterization
• Biomolecular interaction analysis
• Biosensing technologies

Background:

• Biotin-neutravidin interactions are crucial in biological systems and diagnostics.
• Gold nanoparticles offer unique optical properties for sensing applications.
• Light scattering techniques provide label-free methods for analyzing particle size and aggregation.

Purpose of the Study:

• To investigate the aggregation of biotinylated gold nanoparticles induced by neutravidin.
• To evaluate the sensitivity of various light scattering methods for detecting neutravidin.
• To correlate light scattering changes with nanoparticle aggregate size.

Main Methods:

• Dynamic Light Scattering (DLS) for hydrodynamic size measurement.
• Static Light Scattering (SLS) for angular-dependent scattering intensity.
• Resonance Light Scattering (RLS) for wavelength-dependent scattering.
• Angular-ratiometric methods for enhanced sensitivity.

Main Results:

• All light scattering methods detected neutravidin at nanomolar concentrations.
• SLS and RLS showed changes in scattering intensity with scattering angle and wavelength, respectively.
• DLS quantified the increase in hydrodynamic size of nanoparticle aggregates.
• Mie theory predictions correlated scattering changes with aggregate growth.

Conclusions:

• Light scattering approaches are sensitive for detecting neutravidin-induced nanoparticle aggregation.
• These methods hold potential for quantitative analyte detection in biosensing.
• Further evaluation of individual light scattering methods can expand their use in biosensing.