Biaxial Dielectrophoresis Force Spectroscopy: A Stoichiometric Approach for Examining Intermolecular Weak Binding Interactions

In Soo Park, Tae Joon Kwak, Gyudo Lee, Myeonggu Son, Jeong Woo Choi, Seungyeop Choi, Kihwan Nam, Sei Young Lee, Woo Jin Chang, Kilho Eom, Dae Sung Yoon, Sangyoup Lee, Rashid Bashir, Sang Woo Lee

Research output: Contribution to journalArticle

7 Citations (Scopus)


The direct quantification of weak intermolecular binding interactions is very important for many applications in biology and medicine. Techniques that can be used to investigate such interactions under a controlled environment, while varying different parameters such as loading rate, pulling direction, rupture event measurements, and the use of different functionalized probes, are still lacking. Herein, we demonstrate a biaxial dielectrophoresis force spectroscopy (BDFS) method that can be used to investigate weak unbinding events in a high-throughput manner under controlled environments and by varying the pulling direction (i.e., transverse and/or vertical axes) as well as the loading rate. With the BDFS system, we can quantitatively analyze binding interactions related to hydrogen bonding or ionic attractions between functionalized microbeads and a surface within a microfluidic device. Our BDFS system allowed for the characterization of the number of bonds involved in an interaction, bond affinity, kinetic rates, and energy barrier heights and widths from different regimes of the energy landscape.

Original languageEnglish
Pages (from-to)4011-4019
Number of pages9
JournalACS Nano
Issue number4
Publication statusPublished - 2016 Apr 26



  • dielectrophoresis force spectroscopy
  • energy landscape
  • intermolecular weak binding interactions
  • microfluidic device
  • pulling direction

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

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