Dextran Sedimentation
Dextran Sedimentation - Related Videos
08:04
Soxhlet Extraction of Lipid Biomarkers from Sediment
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Sonication Extraction of Lipid Biomarkers from Sediment
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06:17
Measuring Protein Binding to F-actin by Co-sedimentation
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02:56
FITC-Dextran Feeding: A Method to Quantify Intestinal Permeability in C. elegans
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12:00
Preparation and Characterization of SDF-1α-Chitosan-Dextran Sulfate Nanoparticles
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Cited by 9 •
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The objective of this protocol is to incorporate SDF-1α, a stem cell homing factor, into dextran sulfate-chitosan nanoparticles. The resultant particles are measured for their size and zeta potential, as well as the content, activity, and in vitro release rate of SDF-1α from the nanoparticles.
FAQs
Dextran promotes erythrocyte aggregation, including rouleaux formation, in which red cells align into stacked groups. These larger aggregates settle more readily under gravity than individual cells, reducing erythrocyte abundance in the upper plasma layer. The separation therefore depends on the polysaccharide-driven change in red-cell behavior, allowing leukocytes to remain available for subsequent immunological analysis.
Rouleaux formation changes how erythrocytes behave in suspension. As red cells aggregate, they move downward more readily, while leukocytes remain in the upper plasma layer. This differential settling reduces red-cell concentration without requiring a more complex separation approach. The resulting fraction is consequently better suited to examining leukocytes in applications where excessive erythrocyte presence could interfere with analysis.
The workflow begins with whole blood and dextran, allowing the polysaccharide to promote erythrocyte aggregation. The sample is then left under gravity so aggregated red cells settle, after which the upper leukocyte-enriched plasma layer can be collected. This straightforward sequence produces material for downstream microscopy, flow cytometry, culture-based experiments, or additional cell-isolation procedures.
The key determinant is effective erythrocyte aggregation followed by sufficient gravitational settling. Dextran’s high molecular weight supports the aggregation step, while the physical settling process creates the separation between the red-cell-rich lower portion and the leukocyte-containing upper layer. Maintaining this relationship is important because the usefulness of the collected suspension depends on reducing erythrocytes while retaining accessible leukocytes.
This approach provides a leukocyte-enriched starting material for immune-cell characterization and functional assays. In infection studies, the fraction can support investigations of how leukocytes respond to pathogens, while preserving primary-cell material for further work. Its equipment-light and gentle format is particularly relevant when researchers need an accessible preparation step before analyzing cellular responses.
The collected leukocyte-rich fraction can be directed to microscopy, flow cytometry, culture-based experiments, or downstream cell isolation. These options support different kinds of investigation, from observing cellular features to characterizing immune-cell populations or evaluating cell behavior under experimental conditions. The preparation therefore functions as an intermediate sample that connects blood processing with multiple immunological and infection-related readouts.