Sutthinee Mekprayoon and Atitaya Siripinyanond*

The ability of using flow field-flow fractionation (Fl-FFF) coupled off-line with electrothermal atomic absorption spectrometry (ETAAS) for size characterization of AuNPs was investigated. The carrier liquid and membrane affected on particle/membrane or particle/particle interactions in Fl-FFF separation channel. Using DI water with 10 kDa RC membrane provided the best separation of AuNPs. In addition, fractions from the maximum separation peak of AuNPs from Fl-FFF were collected and introduced into ETAAS for gold detection.  The time at the maximum absorbance was increased with increasing particle size.  The advantages of using Fl-FFF with off-line ETAAS were demonstrated to offer reliable size information of AuNPs, both hydrodynamic diameter and core diameter.

Thanks are due to Ministry of Science and Technology, the Royal Thai Government for the scholarship given to SM. We also sincerely acknowledge the Thailand Research Fund (TRF) and Mahidol University for providing the research grant under grant number BRG 6180006. The support from Center of Excellence for Innovation in Chemistry (PERCH-CIC) is gratefully acknowledged.  This work is related to the SDG 4 (Quality Education).