Microfluidics and Nanofluidics

, Volume 9, Issue 6, pp 1051–1062 | Cite as

Electroosmotic flow in a nanofluidic channel coated with neutral polymers

  • Qianqian CaoEmail author
  • Chuncheng Zuo
  • Lujuan Li
  • Yanhong Ma
  • Nan Li
Research Paper


We use molecular dynamics simulations to investigate the control of electroosmotic flow by grafting polymers onto two parallel channel walls. The effects of the grafting density and the electric field strength on electroosmotic flow velocity, counterion distribution and conformational characteristics of grafted chains have been studied in detail for athermal, good, and poor solvent cases. The simulation results indicate that in the range of grafting densities investigated, increasing the grafting density induces a different change tendency of electroosmotic flow velocity for three different solvent qualities. These tendencies are demonstrated to be related to counterion distribution, polymer coverage, and interactions between monomers and solvent particles. It is found that counterions tend to move toward the interface between polymer layer and solvent as the grafting density increases. Especially in the poor solvent case, most of the counterions gather near the interface at high grafting densities. A similar behavior is also observed when enhancing the electric field strength at a fixed grafting density.


Electroosmotic flow Polymer coating Molecular dynamics Solvent quality 



This study was supported by the National Natural Science Foundation of China (No.30770501).


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Qianqian Cao
    • 1
    Email author
  • Chuncheng Zuo
    • 1
  • Lujuan Li
    • 1
  • Yanhong Ma
    • 1
  • Nan Li
    • 1
  1. 1.College of Mechanical Science and EngineeringJilin UniversityChangchunPeople’s Republic of China

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