A robust method using online steric exclusion chromatography-UV-ICPMS to investigate nanoparticle fate and behavior in environmental samples

The foundation of nanoscience is that the properties of materials change as a function of their physicaldimensions, and nanotechnology exploits this premise by applying selected property modifications for a specific benefit.However, to investigate the fate and effect of the engineered nanoparticles on toxic metal (TM) mobility, the analyticallimitations in a natural environment remain a critical problem to overcome. Recently, a new generation of size exclusionchromatography (SEC) columns developed with spherical silica is available for pore sizes between 5 and 400 nm, allowingthe analysis of nanoparticles. In this study, these columns were applied to the analysis of metal-based nanoparticles inenvironmental and artificial samples. The new method allows quantitative measurements of the interactions amongnanoparticles, organic matter and metals. Moreover, due to the new nanoscale SEC, our method allows the study of theseinteractions for different size ranges of nanoparticles and weights of organic molecules with a precision of 1.2 • 10-2 kDa.The method was successfully applied to the study of nano-magnetite spiked in complex matrices, such as sewage sludge,groundwater, tap water and different artificial samples containing Leonardite humic acid and different toxic metals (i.e.,As, Pb, Th). Finally, our results showed that different types of interactions, such as adsorption, stabilization and/ordestabilization of nano-magnetite could be observed using this new method.