Externally Tunable, Low Power Electrostatic Control of Cell Adhesion with Nanometric High‐k Dielectric Films
Abstract
Controlling cell adhesion to surfaces is an important, but difficult, problem. Current methods to control adhesion rely on surface functionalization, which have limited material choice to avoid cell toxicity and are typically cell specific. Herein, cell adhesion is modulated by using nanometric high‐k dielectric films. Voltage is applied across the dielectric film, changing the film surface’s zeta potential, ζ. High performance dielectrics, HfO 2 and SiO 2 , enables a change in the ζ polarity and magnitude over large, 100 mV, ranges by applying ≈1 V across the dielectrics with ≈1nW power draw. Freshwater Chlorella vulgaris and saltwater Nannochloropsis oculata, which have a negative ζ, are used as model cells. Cell adhesion is observed to be inhibited when both surface and cell ζ are negative and enhanced when surface ζ is positive and cell ζ are negative using microfluidic experiments. Finally, millimetric scale cell patterning is demonstrated by spatially modulating ζ with no observed toxicity to cells over 4 weeks.
The authors thank V.D. Castro and D. Speranza at Eni for excellent support throughout the project. The authors thank K. Broderick for help in the cleanroom using the ALD. The authors thank M. Aída for helpful discussions. This work was supported by Eni S.p.A. through the MIT Energy Initiative. Conflict of Interest V.L, B.B., S.S., and K.V. are inventors on a patent application related to this work filed by MIT (V.L., B.B., S.S., and K.V., “Surfaces with modified cell adhesion and related methods,” U.S. application no. 63/388015). The authors declare that they have no other competing interests.
