A Movable Asymmetrical Flow Field-Flow Fractionation System for Size Characterization of Nanoparticles

The performance test of the established AF4 system was carried out with polystyrene or silver reference nanoparticles. In order to investigate trace amounts of natural nanoparticles using AF4, highly sensitive detection method or pre-concentration of samples are necessary. In the present work, liquid waveguide capillary cells (LWCCs) with longer optical path length than 1 cm are adopted for enhancing sensitivity of absorption measurement. The optimum separation conditions of AF4 coupled with LWCC system and the limit of detection (LOD) of different cells will be discussed. A movable AF4 system was developed and tested for separation and size characterization of polystyrene and silver reference nanoparticles. For the enhancement of sensitivity on absorption measurement, LWCC with longer optical path length than 1 cm was coupled with the developed AF4 system and the optimized condition of AF4-LWCC system was obtained. The developed AF4 system will be combined with laser-induced breakdown detection (LIBD) for analysis of trace nanoparticles in natural water