Sub-micron particle analysis by thermal field-flow fractionation and multi-angle light scattering detection

Experimental Evidence of Thermophoresis of Non-Brownian Particles in Pure Liquids and Estimation of Their Thermophoretic Mobility

“…These values are about 1 order of magnitude smaller than the values obtained by McNab and Meisen for PS latex particles suspended in either n -hexane or water . Still the latter values are nearly two-orders of magnitude larger than those obtained for PS submicron latex colloids by thermal FFF in aqueous salt or surfactants solutions. ,,,, These particles generally exhibit larger D T values in a salt acetonitrile solution than in aqueous solutions 38,50 or when the acetonitrile content of mixtures with water increases …”

“…13 Still the latter values are nearly two-orders of magnitude larger than those obtained for PS submicron latex colloids by thermal FFF in aqueous salt or surfactants solutions. 15,16,23,24,50 These particles generally exhibit larger D T values in a salt acetonitrile solution than in aqueous solutions 38,50 or when the acetonitrile content of mixtures with water increases. 24 The D T values reported in the thermal FFF literature for Si-OH or Si-ODS submicron particles cannot be straightforwardly compared with data of Table 1 because they were obtained, not in pure liquids, but in aqueous or organic solutions with varying concentrations of salts or surfactants.…”

“…15,16,23,24,50 These particles generally exhibit larger D T values in a salt acetonitrile solution than in aqueous solutions 38,50 or when the acetonitrile content of mixtures with water increases. 24 The D T values reported in the thermal FFF literature for Si-OH or Si-ODS submicron particles cannot be straightforwardly compared with data of Table 1 because they were obtained, not in pure liquids, but in aqueous or organic solutions with varying concentrations of salts or surfactants. In aqueous solutions, D T values appear to be only slightly dependent on Si-OH particle size and to be in the range of (1-4) × 10 -12 m 2 s -1 K -1 , the value increasing with increasing salt or surfactant concentration.…”

“…13 Thermal FFF experiments confirmed this evidence 14,15 and demonstrated it for other kinds of latex and colloidal particles, such as silica, 14 polybutadienes, 16,17 poly(methyl methacrylate)s, silanized silica, styrene-vinylbenzyl chloride copolymer latex, and, even, palladium particles, 17 before it was observed by forced Rayleigh scattering 18,19 and the thermogravitational column method. 20 Later on, the effect was demonstrated for other types of particles, core-shell latex, 21 acrylonitrile-butadiene-styrene plastic, rubber, 22 modified silica, 23 styrene-butyl methacrylate latex, 24 and metal (silver, gold, platinum) 25 particles. The influence of various operational parameters on D T was investigated in several of these studies (see also ref 26).…”

DNA separation by EFFF in a microchannel

“…There is an extensive literature on the use of EFFF [16][17][18] and other variants of FFF such as those based on gravity, centrifugal acceleration [19][20][21], lateral fluid flow [22], or thermal field-flow fractionation (TFFF) [23][24][25]. These techniques have been used in separations of a number of different types of molecules including biomolecules [26,27].…”