Article

Annals of Biomedical Engineering

, Volume 38, Issue 12, pp 3777-3788

Open Access This content is freely available online to anyone, anywhere at any time.

Efficient Dielectrophoretic Patterning of Embryonic Stem Cells in Energy Landscapes Defined by Hydrogel Geometries

  • Hideaki TsutsuiAffiliated withDepartment of Mechanical and Aerospace Engineering, University of California, Los Angeles
  • , Edmond YuAffiliated withDepartment of Mechanical and Aerospace Engineering, University of California, Los Angeles
  • , Sabrina MarquinaAffiliated withDepartment of Mechanical and Aerospace Engineering, University of California, Los Angeles
  • , Bahram ValamehrAffiliated withDepartment of Molecular and Medical Pharmacology, University of California, Los Angeles
  • , Ieong WongAffiliated withDepartment of Mechanical and Aerospace Engineering, University of California, Los Angeles
  • , Hong WuAffiliated withDepartment of Molecular and Medical Pharmacology, University of California, Los Angeles
  • , Chih-Ming HoAffiliated withDepartment of Mechanical and Aerospace Engineering, University of California, Los Angeles Email author 

Abstract

In this study, we have developed an integrated microfluidic platform for actively patterning mammalian cells, where poly(ethylene glycol) (PEG) hydrogels play two important roles as a non-fouling layer and a dielectric structure. The developed system has an embedded array of PEG microwells fabricated on a planar indium tin oxide (ITO) electrode. Due to its dielectric properties, the PEG microwells define electrical energy landscapes, effectively forming positive dielectrophoresis (DEP) traps in a low-conductivity environment. Distribution of DEP forces on a model cell was first estimated by computationally solving quasi-electrostatic Maxwell’s equations, followed by an experimental demonstration of cell and particle patterning without an external flow. Furthermore, efficient patterning of mouse embryonic stem (mES) cells was successfully achieved in combination with an external flow. With a seeding density of 107 cells/mL and a flow rate of 3 μL/min, trapping of cells in the microwells was completed in tens of seconds after initiation of the DEP operation. Captured cells subsequently formed viable and homogeneous monolayer patterns. This simple approach could provide an efficient strategy for fabricating various cell microarrays for applications such as cell-based biosensors, drug discovery, and cell microenvironment studies.

Keywords

Poly(ethylene glycol) Surface engineering Cell microarray Microfluidics Dielectrophoresis