Resonance rayleigh scattering method to detect avidin using affinity Au nanoparticles was studied.

This system was quick and sensitive for avidin detection due to avidin–biotin affinitive interaction.

Resonance rayleigh scattering intensity of biotin–AuNPs increase linearly with the increasing concentration of avidin.

This method was applied to quantitative determination of the avidin in synthetic samples and egg products with stable recovery and RSD value.