Flow field-flow fractionation for the analysis and characterization of natural colloids and manufactured nanoparticles in environmental systems: A critical review

The use of flow field flow fractionation (FIFFF) for the separation and characterization of natural colloids and nanoparticles has increased in the last few decades. More recently, it has become a popular method for the characterization of manufactured nanoparticles. Unlike conventional filtration methods, FIFFF provides a continuous and high-resolution separation of nanoparticles as a function of their diffusion coefficient, hence the interest for use in determining particle size distribution. Moreover, when coupled to other detectors such as inductively coupled plasma-mass spectroscopy, light scattering. UV-absorbance, fluorescence, transmission electron microscopy, and atomic force microscopy, FIFFF provides a wealth of information on particle properties including, size, shape, structural parameters, chemical composition and particle-contaminant association. This paper will critically review the application of FIFFF for the characterization of natural colloids and natural and manufactured nanoparticles. Emphasis will be given to the detection systems that can be used to characterize the nanoparticles eluted from the FIFFF system, the obtained information and advantages and limitation of FIFFF compared to other fractionation and particle sizing techniques. This review will help users understand (i) the theoretical principles and experimental consideration of the FIFFF, (ii) the range of analytical tools that can be used to further characterize the nanoparticles after fractionation by FIFFF, (iii) how FIFFF results are compared to other analytical techniques and (iv) the range of applications of FIFFF for natural and manufactured NPs. (C) 2011 Elsevier B.V. All rights reserved.