Sedimentation field flow fractionation and optical absorption spectroscopy for a quantitative size characterization of silver nanoparticles

The first method, based on the application of Mie's theory, determines the particle sizes from the values of the surface plasmon resonance wavelength (SPRmAx), read from the optical absorption spectra, recorded between 190 nm and 800 nm. The computed sizes were compared with those determined by transmission electron microscopy (TEM) and dynamic light scattering (DLS) and resulted in agreement with the nominal values in a range between 13% (for 20 nm NPs) and 1% (for 100 nm NPs),

Many advanced industrial and biomedical applications that use silver nanoparticles (AgNPs), require that particles are not only nano-sized, but also well dispersed, not aggregated and not agglomerated. This study presents two methods able to give rapidly sizes of monodispersed AgNPs suspensions in the dimensional range of 20-100 nm.