Skip to main content
Log in

Viscosity-difference-induced asymmetric selective focusing for large stroke particle separation

  • Research Paper
  • Published:
Microfluidics and Nanofluidics Aims and scope Submit manuscript

Abstract

We developed a new approach for particle separation by introducing viscosity difference of the sheath flows to form an asymmetric focusing of sample particle flow. This approach relies on the high-velocity gradient in the asymmetric focusing of the particle flow to generate a lift force, which plays a dominated role in the particle separation. The larger particles migrate away from the original streamline to the side of the higher relative velocity, while the smaller particles remain close to the streamline. Under high-viscosity (glycerol–water solution) and low-viscosity (PBS) sheath flows, a significant large stroke separation between the smaller (1.0 μm) and larger (9.9 μm) particles was achieved in a sample microfluidic device. We demonstrate that the flow rate and the viscosity difference of the sheath flows have an impact on the interval distance of the particle separation that affects the collected purity and on the focusing distribution of the smaller particles that affects the collected concentration. The interval distance of 293 μm (relative to the channel width: 0.281) and the focusing distribution of 112 μm (relative to the channel width: 0.107) were obtained in the 1042-μm-width separation area of the device. This separation method proposed in our work can potentially be applied to biological and medical applications due to the wide interval distance and the narrow focusing distribution of the particle separation, by easy manufacturing in a simple device.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

Similar content being viewed by others

References

Download references

Acknowledgments

We acknowledge the Natural Science Foundation of Hubei Province of China (No. 2015CFA110) and National Natural Science Foundation of China (No. 51575216) for financial support. Wu thanks the support from the Chinese central government through its Thousand Youth Talents program.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Zhigang Wu.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (MP4 12352 kb)

Supplementary material 2 (PDF 665 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Xu, W., Hou, Z., Liu, Z. et al. Viscosity-difference-induced asymmetric selective focusing for large stroke particle separation. Microfluid Nanofluid 20, 128 (2016). https://doi.org/10.1007/s10404-016-1791-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s10404-016-1791-5

Keywords

Navigation