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Talk:Electroosmotic flow

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Uh the example of flow in a tube is slightly wrong. While the ion behaviour is correct the aggregation of ions in the debye layer near the surface in the case of a tube (a.k.a. cylinder) geometry is actually due to electrostatic repulsion of the ions in the bulk and not attraction caused by the surface charges. This follows from Gauss' Law which when applied shows a surface charge in such a geometry produces no forces on the ions contained within it. Similar story for the two plates. I don't know how to write this clearly, somebody else want to take a stab?

I'm only a novice at electrophoresis so i'm not complaining lol. But could someone mention the disadvantages of this phenomenon

It's basically a wall effect. If you notice the electrophorograms usually have bands which are kind of bent at the edges. I believe this is at least partially due to EOF (I think it is also due to adsorption of DNA on to the surface).

Not quite true. The surface effects are actually very important. There is much research being conducted on surface treatments to enhance EOF. While I cannot say whether the ion aggregation is moreso a factor of attraction to the wall or repulsion from the bulk, it is two heads of the same coin. The fact is the governing principle is the charge induced at the surface interface, which is governed mainly by the type of surface itself and the behavior of the ions within the fluid, which is governed by the bulk fluid. Knowledge of both is required to determine EOF. 204.52.215.1 (talk) 20:21, 20 January 2010 (UTC)[reply]