Sedimentation field-flow fractionation colloids

C. M. Frietch, and C. A. Kelly. Characterization of Submicron Aqueous Iron(lll) Colloids by Sedimentation Field Flow Fractionation, Anal Chem. 2001, 73.4815.)... 

Contado, C., Bio, G., Fagioli, F., Dondi, F., and Beckett, R. (1997). Characterization of River Po particles by sedimentation field-flow fractionation coupled to GFAAS and ICP-MS. Colloids Surf. A 120,47-59. 

Murphy, D.M., Garbarino, J.R., Taylor, H.E., Hart, B.T. and Beckett, R. (1993) Determination of size and element composition distributions of complex colloids by sedimentation field-flow fractionation-inductively coupled plasma mass spectrometry. /. Chromatogr., 642, 459M67. 

Measuring Particle Size Distribution of Simple and Complex Colloids Using Sedimentation Field-Flow Fractionation... 

This paper outlines the basic principles and theory of sedimentation field-flow fractionation (FFF) and shows how the method is used for various particle size measurements. For context, we compare sedimentation FFF with other fractionation methods using four criteria to judge effective particle characterization. The application of sedimentation FFF to monodisperse particle samples is then described, followed by a discussion of polydisperse populations and techniques for obtaining particle size distribution curves and particle densities. We then report on preliminary work with complex colloids which have particles of different chemical composition and density. It is shown, with the help of an example, that sedimentation FFF is sufficiently versatile to unscramble complex colloids, which should eventually provide not only particle size distributions, but simultaneous particle density distributions. 

Colloid Characterization by Sedimentation Field-Flow Fractionation. I. Monodis-perse Populations, J. C. Giddings, G. Karaiskakis, K. D. Caldwell, and M. N. Myers, J. Colloid Interface Sci., 92, 66 (1983). 

Separation and Size Characterization of Colloidal Particles in River Water by Sedimentation Field-Flow Fractionation, R. Beckett, G. Nicholson, B. T. Hart, M. Hansen, and J. C. Giddings, Wat. Res., 22, 1535 (1988). 

Giddings JC, Caldwell KD, Jones HK (1987) Measuring particle size distribution of simple and complex colloids by sedimentation field-flow fractionation. In Provder T (ed) Particle size distribution assessment and characterization. American Chemical Society, Washington, DC,pp 215-230... 

Ranville, J.F. et al., Development of sedimentation field-flow fractionation-inductively coupled plasma mass-spectrometry for the characterization of environmental colloids, Anal. Chim. Acta, 381, 315, 1999. 

Hassellov, M., Lyven, B., and Beckett, R., Sedimentation field-flow fractionation coupled online to inductively coupled plasma mass spectrometry New possibilities for studies of trace metal adsorption onto natural colloids, Environ. Sci. Technol., 33, 4528-, 1999. 

Sedimentation field-flow fractionation was used also for the kinetic study of hydroxyapatite (HAP) particles aggregation in the presence of various electrolytes to determine the rate constants for the bimol-ecular process of aggregation and to investigate the possible aggregation mechanisms describing the experimental data. The HAP sample contained polydis-perse, irregular colloidal particles with number-average diameter dys = 0.262 + 0.046 /rm. 

Blau P, Zollars RL Sedimentation Field-Flow Fractionation of Nonspherical Particles. Journal of Colloid and Interface Science 1996, 183 476-483. 

Giddings, J.C. Karaiskakis, G. Caldwell, K.D. Myers, MJ4. Colloid characterization by sedimentation field-flow fractionation I. Monodisperse populations. J. Colloid Interf. Sci. 1983, 92 (1), 66. 

Athanasopoulou, A. Karaiskakis, G. Travlos, A. Colloidal interactions studied by sedimentation field-flow fractionation. J. Liq. Chromatogr. Relat. Technol. 1997, 20 (16), 2525-2541. 

Source From Resolution of colloidal latex aggregates by sedimentation field-flow fractionation, in J. Chromatogr. Copyright Elsevier Science PubUshers B.V. 

Karaiskakis, G. Graff, K.A. Caldwell, K.D. Giddings, J.C. Sedimentation field-flow fractionation of colloidal particles in river water. Int. J. Environ. Anal. Chem. 1982,12, 1. 

Caldwell, K.D. Li, J. Emulsion characterization by the combined sedimentation field-flow fractionation-photon correlation spectroscopy methods. J. Colloid Interface Sci. 1989,132, 256-268. 

Magnuson, M.L. Lytle, D.A. Frietch, C.M. Kelly, C.A. Characterization of submicrometer aqueous iron HI colloids formed in the presence of phosphate by sedimentation field-flow fractionation with multiangle laser tight scattering detection. Anal. Chem. 2001, 73, 4815 820. 

Beckett, R. Nicholson, G. Hart, B.T. Hansen, M. Giddings, J.C. Separation and size characterization of colloidal particles in river water by sedimentation field-flow fractionation. Water Res. 1988, 22 (12), 1535-1545. 

Hansen, M.E. Giddings, J.C. Beckett, R. Colloid characterization by sedimentation field-flow fractionation VI. Perturbations due to overloading and electrostatic repulsion. J. CoUoid. Interf. Sci. 1989,132 (2), 300. 

The study of the interfacial phenomena between the channel wall and the colloidal suspension under study in sedimentation field-flow fractionation (SdFFF) is of great significance in investigating the resolution of the SdFFF separation method and its accuracy in determining particles physicochemical quantities. The particle-wall interactions in SdFFF affect the exponential transversal distribution of the analyte and the parabolic flow profile, leading to deviations from the classical retention theory, thus influencing the accuracy of analyte quantities measured by SdFFF. Among the various particle-wall interactions, our discussion focuses on the van der Waals attractive and electrostatic repulsion forces, which play dominant roles in SdFFF surface phenomena. 

By coupling flow field-flow fractionation (flow FFF) to ICP-MS it is possible to investigate trace metals bound to various size fractions of colloidal and particulate materials.55 This technique is employed for environmental applications,55-57 for example to study trace metals associated with sediments. FFF-ICP-MS is an ideal technique for obtaining information on particle size distribution and depth profiles in sediment cores in addition to the metal concentrations (e.g., of Cu, Fe, Mn, Pb, Sr, Ti and Zn with core depths ranging from 0-40 cm).55 Contaminated river sediments at various depths have been investigated by a combination of selective extraction and FFF-ICP-MS as described by Siripinyanond et al,55... 

Clearly, sedimentation FFF is a separation technique. It is an important member of the field-flow fractionation (FFF) family of techniques. Although other members of the FFF family (especially thermal FFF) are more effective for polymer analysis, sedimentation FFF is advantageous for the separation of a wide assortment of colloidal particles. Sedimentation FFF not only yields higher resolution than nearly all other particle separation techniques, but its simple theoretical basis allows a straightforward connection between observed particle migration rates and particle size. Thus size distribution curves are readily obtained on the basis of theoretical analysis without the need for (and uncertainties of) calibration. 

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