Applied Electric Fields Polarize Initiation and Growth of Endothelial Sprouts

Figure 7

Cathode-directed electro-osmotic flow continues near negatively charged surfaces during zero net fluid flow in a closed channel. (a) Electro-osmotic flow toward the cathode is modelled through a 1 μm tall channel forming a plug flow profile [29]. (b) A reverse direction pressure gradient is modelled and generates a parabolic flow profile through the 1 μm tall channel with the same average volumetric flow rate. (c) Simultaneous application of both flows generates slightly reduced flow velocity next to the charged walls, and backflow through the lowest resistance pathway, the center of the channel. In vitro, fibrin gels have pore sizes ranging from 3 to 10 μm depending on preparation conditions [30, 31]. Therefore, EOF next to charged fibrin and charged sprout surfaces continues in a closed system and the pressure gradients dissipate through the low resistance center of the pores.

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(b)

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