Microfluidics and Nanofluidics

, Volume 14, Issue 1–2, pp 69–76 | Cite as

Microfabrication-free fused silica nanofluidic interface for on chip electrokinetic stacking of DNA

  • Da-Wei Zhang
  • Hui-Qin Zhang
  • Li Tian
  • Lin Wang
  • Fang Fang
  • Kun Liu
  • Zhi-Yong WuEmail author
Research Paper


In this article, a simple but robust nanofluidic interface was introduced directly on a chip comprised of commercially available fused silica capillary with ready-made microchannel, and efficient on chip electrokinetic stacking of DNA was successfully demonstrated based on ion concentration polarization (ICP) effect. The nanofluidic interface was established by casting ion exchange polymer resin (Nafion) into a sub-microfracture (~650 nm) prepared on the capillary manually. The width of the fracture was electrically measured with the aide of a mathematic fracture model and confirmed by scanning electronic microscope. Obvious ICP effect was observed both by online microscopic fluorescent imaging and post laser induced fluorescence detection. SYBR Green I labeled dsDNA was stacked at the nanofluidic interface inside the microchannel (cathode side) with a concentration factor of 103 within 15 s. As high as 800 V was applied through the interface without any damage. The main materials are all commercially available, and no advanced microfabrication facilities are involved in the preparation of the chip.


Nanofluidic interface Fused silica capillary Nafion Microfracture Ion concentration polarization DNA Electrokinetic stacking 



Financial supports from NSFC (20975018), Liaoning Educational Department (2009S038) and the University are highly appreciated.

Supplementary material

Supplementary material 1 (AVI 144 kb)

Supplementary material 2 (AVI 537 kb)

10404_2012_1023_MOESM3_ESM.docx (213 kb)
Supplementary material 3 (DOCX 213 kb)


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Da-Wei Zhang
    • 1
  • Hui-Qin Zhang
    • 1
  • Li Tian
    • 1
  • Lin Wang
    • 1
  • Fang Fang
    • 1
    • 2
  • Kun Liu
    • 3
  • Zhi-Yong Wu
    • 1
    Email author
  1. 1.Research Center for Analytical SciencesNortheastern UniversityShenyangChina
  2. 2.Department of ChemistryNortheastern UniversityShenyangChina
  3. 3.Research Institute of Vacuum and FluidNortheastern UniversityShenyangChina

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