Directional pumping of water and oil microdroplets on slippery surface

Jieke Jiang, Jun Gao, Hengdi Zhang, Wenqing He, Jianqiang Zhang, Dan Daniel, Xi Yao*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

53 Citations (Scopus)
1 Downloads (Pure)


Transporting water and oil microdroplets is important for applications ranging from water harvesting to biomedical analysis but remains a great challenge. This is due to the amplified contact angle hysteresis and insufficient driving force in the micrometer scale, especially for low-surface energy oil droplets. Coalescence of neighboring droplets, which releases vast additional surface energy, was often required, but its relatively uncontrollable nature brings uncertainties to the droplet motion, and the methodology is not applicable to single droplets. Here we introduce a strategy based on slippery surface with immobilized lubricant menisci to directionally transport microdroplets. By simply mounting hydrogel dots on slippery surface, the raised menisci remotely pump microdroplets via capillary force with high efficiency, regardless of droplet size or surface energy. By proof-of-concept experiments, we demonstrate that our method allows for highly efficient water droplet collection and highly sensitive biomedical analyte detection.

Original languageEnglish
Pages (from-to)2482-2487
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number7
Publication statusPublished - 12 Feb 2019


  • Antifouling
  • Capillary force
  • Droplet transport
  • Microdroplet
  • Slippery surface


Dive into the research topics of 'Directional pumping of water and oil microdroplets on slippery surface'. Together they form a unique fingerprint.

Cite this