Liquid parameter free method for nanoparticle size determination based on dynamic light scattering

A ratio of diameter method based on dynamic light scattering was proposed to measure the size of nanoparticles. In the measurement process, parameters, such as the surrounding temperature T, the viscous coefficient η, and the refractive index n0 of the solvent and the scattering angle θ and the wavelength of the light λ0 in vacuum, are not needed. The only requirement is to provide a particle sample with a known diameter as a reference. After the intensity autocorrelation function values and baseline values are measured, the ratio of diameters from two kinds of particles can be calculated and the size of the sample particles can be deduced. The data analysis process is simple, convenient, and effective. When this method is applied to a polydisperse sample, the intensity-weighted mean diameter can be obtained.