Abstract
This paper reports a method for label‐free single‐cell biophysical analysis of multiple cells trapped in suspension by electrokinetic forces. Tri‐dimensional pillar electrodes arranged along the width of a microfluidic chamber define actuators for single cell trapping and selective release by electrokinetic force. Moreover, a rotation can be induced on the cell in combination with a negative DEP force to retain the cell against the flow. The measurement of the rotation speed of the cell as a function of the electric field frequency define an electrorotation spectrum that allows to study the dielectric properties of the cell. The system presented here shows for the first time the simultaneous electrorotation analysis of multiple single cells in separate micro cages that can be selectively addressed to trap and/or release the cells. Chips with 39 micro‐actuators of different interelectrode distance were fabricated to study cells with different sizes. The extracted dielectric properties of Henrietta Lacks, human embryonic kidney 293, and human immortalized T lymphocytes cells were found in agreements with previous findings. Moreover, the membrane capacitance of M17 neuroblastoma cells was investigated and found to fall in in the range of 7.49 ± 0.39 mF/m2.
Highlights
Electrorotation (ROT) is a label-free analysis technique [1, 2], which can read out the dielectric properties of cells
The system presented here shows for the first time the simultaneous electrorotation analysis of multiple single cells in separate micro cages that can be selectively addressed to trap and/or release the cells
We apply the vertical electrodes integration approach that we presented in previous works [8, 9] to develop a system for single cells arraying and parallel electrorotation analysis in 50 μm high microfluidic chambers (Fig. 1B)
Summary
Electrorotation (ROT) is a label-free analysis technique [1, 2], which can read out the dielectric properties of cells. It can differentiate between cell lines [3], observe cell membrane changes [4,5,6], or investigate the cytoplasm properties of cells [7], to only mention some examples. Existing systems employing this technique suffer from a very low parallel operation. Each electrode is connected to a dedicated pad to allow the independent control of each single-cell actuator to capture a cell, retain it, rotate it by electric field of varying frequencies while being held against the flow, and selectively released
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
