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Characterization of nonspecific crossover in split-flow thin channel fractionation
P Stephen Williams1, Mauricio Hoyos, Pascal Kurowski
1Department of Biomedical Engineering, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, Ohio 44195, USA. willias3@ccf.org
Split-flow thin channel (SPLITT) fractionation separates particles using a field-induced lateral migration. This study investigates nonspecific crossover (NSC) in SPLITT, exploring shear-induced diffusion (SID) as a potential cause.
Area of Science:
- Biophysics
- Separation Science
- Fluid Dynamics
Background:
- Split-flow thin channel (SPLITT) fractionation is a continuous separation technique based on field-induced lateral migration.
- Applications include isolating fractions from polydisperse samples and separating labeled from unlabeled cells using transverse fields.
- Nonspecific crossover (NSC) is a critical issue in cell separation, referring to the undesired migration of nonmobile particles into mobile streams.
Purpose of the Study:
- To investigate the mechanisms of nonspecific crossover (NSC) in split-flow thin channel (SPLITT) fractionation.
- To evaluate the role of shear-induced diffusion (SID) in causing NSC, particularly in the context of immunomagnetically labeled cell separation.
- To provide insights for optimizing SPLITT fractionation protocols to minimize contamination and maximize throughput.
Main Methods:
- Review and discussion of potential mechanisms for nonspecific crossover (NSC).
- Experimental interpretation of results in terms of shear-induced diffusion (SID) in a sheared flow.
- Analysis of viscous interactions between particles contributing to NSC.
Main Results:
- Nonspecific crossover (NSC) can lead to contamination in SPLITT fractionation, impacting the purity of separated fractions.
- Shear-induced diffusion (SID), arising from viscous interactions in sheared flow, is identified as a potential contributor to NSC.
- Experimental data suggests SID plays a role, but its exact contribution requires further investigation.
Conclusions:
- Shear-induced diffusion (SID) may contribute to nonspecific crossover (NSC) in split-flow thin channel (SPLITT) fractionation.
- Minimizing NSC is crucial for applications like separating labeled and unlabeled cells, requiring careful optimization of flow and field conditions.
- Further experimental validation and mathematical modeling are necessary to fully understand and mitigate NSC in SPLITT systems.
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