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Title: Cell Surface Charge Mapping Using a Microelectrode Array on ITO Substrate
Many cellular functions are regulated by cell surface charges, such as intercellular signaling and metabolism. Noninvasive measurement of surface charge distribution of a single cell plays a vital role in understanding cellular functions via cell membranes. We report a method for cell surface charge mapping via photoelectric interactions. A cell is placed on an array of microelectrodes fabricated on a transparent ITO (indium tin oxide) surface. An incident light irradiates the ITO surface from the backside. Because of the influence of the cell surface charge (or zeta potential), the photocurrent and the absorption of the incident light are changed, inducing a magnitude change of the reflected light. Hence, the cell surface charge distribution can be quantified by analyzing the reflected light intensity. This method does not need physical or chemical modification of the cell surface. We validated this method using charged microparticles (MPs) and two types of cells, i.e., human dermal fibroblast cells (HDFs) and human mesenchymal stem cells (hMSC). The measured average zeta potentials were in good agreement with the standard electrophoresis light scattering method.  more » « less
Award ID(s):
1905786 1911526
PAR ID:
10421092
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Cells
Volume:
12
Issue:
4
ISSN:
2073-4409
Page Range / eLocation ID:
518
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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