Elasto-inertial microfluidic separation offers many advantages including high throughput and separation resolution.Even though the separation efficiency highly depends on precise control of the flow conditions,no conc...Elasto-inertial microfluidic separation offers many advantages including high throughput and separation resolution.Even though the separation efficiency highly depends on precise control of the flow conditions,no concrete guidelines have been reported yet in elasto-inertial microfluidics.Here,we propose a dimensionless analysis for precise estimation of the microsphere behaviors across the interface of Newtonian and viscoelastic fluids.Reynolds number,modified Weissenberg number,and modified elastic number are used to investigate the balance between inertial and elastic lift forces.Based on the findings,we introduce a new dimensionless number defined as the width of the Newtonian fluid stream divided by microsphere diameter.The proposed dimensionless analysis allows us to predict whether the microspheres migrate across the co-flow interface.The theoretical estimation is found to be in good agreement with the experimental results using 2.1-and 3.2-μm-diameter polystyrene microspheres in a co-flow of water and polyethylene oxide solution.Based on the theoretical estimation,we also realize submicron separation of the microspheres with 2.1 and 2.5μm in diameter at high throughput,high purity(>95%),and high recovery rate(>97%).The applicability of the proposed method was validated by separation of platelets from similar-sized Escherichia coli(E.coli).展开更多
基金supported in part by Samsung Display Company Ltd.and in part by the National Research Foundation of Korea(NRF)grants funded by the Korean government(MSIT)(Nos.RS-2023-00210891 and 2020R1A5A8018367).
文摘Elasto-inertial microfluidic separation offers many advantages including high throughput and separation resolution.Even though the separation efficiency highly depends on precise control of the flow conditions,no concrete guidelines have been reported yet in elasto-inertial microfluidics.Here,we propose a dimensionless analysis for precise estimation of the microsphere behaviors across the interface of Newtonian and viscoelastic fluids.Reynolds number,modified Weissenberg number,and modified elastic number are used to investigate the balance between inertial and elastic lift forces.Based on the findings,we introduce a new dimensionless number defined as the width of the Newtonian fluid stream divided by microsphere diameter.The proposed dimensionless analysis allows us to predict whether the microspheres migrate across the co-flow interface.The theoretical estimation is found to be in good agreement with the experimental results using 2.1-and 3.2-μm-diameter polystyrene microspheres in a co-flow of water and polyethylene oxide solution.Based on the theoretical estimation,we also realize submicron separation of the microspheres with 2.1 and 2.5μm in diameter at high throughput,high purity(>95%),and high recovery rate(>97%).The applicability of the proposed method was validated by separation of platelets from similar-sized Escherichia coli(E.coli).