Elasto-inertial particle focusing in 3D-printed microchannels with unconventional cross sections

  • Wenlai Tang
  • Ning Fan
  • Jiquan Yang
  • Zongan Li
  • Liya Zhu
  • Di Jiang
  • Jianping ShiEmail author
  • Nan XiangEmail author
Research Paper
Part of the following topical collections:
  1. Particle motion in non-Newtonian microfluidics


In this paper, elasto-inertial particle focusing in 3D-printed microchannels with unconventional cross sections was studied. A novel 3D-printed mold-removal method was proposed to fabricate the microchannels. By modifying the orifice shape of the extrusion nozzle, the microchannel molds with arbitrary cross sections could be printed using an easily accessible fused deposition modeling (FDM) printer. After the routine PDMS casting procedure, the channel molds were dissolved to produce all-PDMS microfluidic chips, thereby eliminating the complex bonding process. The mechanisms of elasto-inertial focusing in the semielliptical and triangular microchannels were explored by comparing the particle migrations in 0.3 wt% HA solution and PBS solution, and the effects of flow rate on particle focusing position and focusing width were also investigated. We found that the single-line particle focusing in the triangular microchannel was more stable and closer to the channel bottom than that in the semielliptical microchannel, which is of great value to improve the detection sensitivity of microfluidic impedance cytometer with coplanar electrodes fabricated on the channel bottom.


Elasto-inertial focusing 3D printing Particle migration Unconventional cross section Microfluidics 



This work was supported by the National Natural Science Foundation of China (Nos. 51805272, 51705259, 51875103), the National Key R&D Program of China (No. 2017YFB1103200), the Key Technology R&D Program of Jiangsu Province (Nos. BE2018010-1, BE2018010-2) and the Natural Science Fund for Colleges and Universities in Jiangsu Province (No. 18KJB460022).


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.School of Electrical and Automation Engineering, Jiangsu Key Laboratory of 3D Printing Equipment and ManufacturingNanjing Normal UniversityNanjingPeople’s Republic of China
  2. 2.Nanjing Institute of Intelligent High-end Equipment Industry Co., LtdNanjingPeople’s Republic of China
  3. 3.School of Mechanical and Electronic EngineeringNanjing Forestry UniversityNanjingPeople’s Republic of China
  4. 4.School of Mechanical Engineering, Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical InstrumentsSoutheast UniversityNanjingPeople’s Republic of China

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