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Asymmetrical Flow Field-Flow Fractionation for Sizing of Gold Nanoparticles in Suspension
Published on: September 11, 2020
On the no-field method for void time determination in flow field-flow fractionation
Michel Martin1, Mauricio Hoyos
1Ecole Supérieure de Physique et de Chimie Industrielles, Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH-UMR 7636 CNRS-ESPCI ParisTech-Université Pierre et Marie Curie-Université Paris-Diderot), 10 rue Vauquelin, 75231 Paris Cedex 05, France. martin@pmmh.espci.fr
Journal of Chromatography. A
|January 25, 2011
Summary
In flow field-flow fractionation (flow FFF), a new model explains unexpectedly long elution times by carrier liquid bypassing the channel through porous walls. This finding is crucial for accurate void time determination in FFF systems.
Area of Science:
- Analytical Chemistry
- Separation Science
- Physical Chemistry
Background:
- Flow field-flow fractionation (flow FFF) is a versatile separation technique.
- Accurate determination of void time is essential for quantitative analysis in FFF.
- Previous methods for void time determination in flow FFF have limitations.
Purpose of the Study:
- To investigate and explain the unexpectedly long elution times observed in a symmetrical flow FFF system under no-field conditions.
- To develop and validate a flow model that accounts for carrier liquid flow through porous walls.
- To provide a basis for accurate void time determination in flow FFF.
Main Methods:
- Experimental measurements of elution times for colloidal particles in a symmetrical flow FFF system with closed cross-flow.
- Development of a flow model considering carrier liquid flow through porous walls and reservoirs.
- Measurement of frit permeabilities to validate the model.
- Comparison of predicted elution times with experimental data.
Main Results:
- Observed elution times were significantly longer than predicted by geometrical volume and flow rate alone.
- A developed flow model, incorporating carrier liquid flow through porous walls, successfully explained the discrepancies.
- The ratio of observed to expected elution time depends on a parameter related to porous element and channel dimensions.
- Measured frit permeabilities allowed for reasonable agreement between predicted and experimental elution times.
Conclusions:
- The carrier liquid primarily bypasses the channel, flowing through porous walls into reservoirs and back into the channel.
- The developed flow model accurately describes the 'no-field' elution behavior in flow FFF.
- Accurate hydrodynamic characteristics of permeable elements are important for manufacturers to provide for better void time estimation.
- The model is applicable to both symmetrical and asymmetrical flow FFF systems.
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