Ceramic hollow fibers have been used as separation channels for flow field-flow fractionation. The fibers were made of alpha-alumina, with a gamma-alumina layer on the inside wall acting as a semipermeable (ultrafiltration) membrane. The fibers and the separation system were tested by determining the diffusion coefficients of a series of standard proteins under various experimental conditions.
View Article and Find Full Text PDFFlat channel asymmetrical flow field-flow fractionation with multi-angle light scattering (MALS) detection was used to study the swelling behaviour of core-shell particles with either carboxylated or hydroxylated shells as a function of pH and ionic strength. The equilibration time of the most heavily carboxylated core-shells appeared to be of the order of several hours. At low ionic strength (5 mM), the carboxylated core-shells showed a definite swelling response to a change in pH in the range from 5 to 10, ranging from a hydrodynamic radius increase of 24 to 118%, depending on the degree of carboxylation.
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