Electrophoresis

This is the migration of ionized species under the influence of an electric field. Ions in an electric field experience a force proportional to their charge, causing them to accelerate in the direction of the field. Ions in solution, not interacting with a solid support, reach a terminal velocity dependent on the magnitude of the force and their interaction with the solvent. Therefore, different ions will migrate through the solvent at different rates. This can be used to separate different ions and is known as free solution elec-trophoresis.

If the solvent is within a bed of chromatographi-cally active media such as silica, the migrating ions can interact with the solid support, adding a chromatographic component to the separation. At this point, it is simpler to refer to the separation as electrochromatography, which encompasses both electrophoretic and chromatographic effects.

The ionic mobility u can be expressed in terms of the ion's velocity v in a given electric field strength Eby u = v/E. This only applies to free solutions, since migration through the channels of a solid support follows a tortuous path that deviates from a straight line by a quantity dependent upon the properties of the solid support. The important point is that the migration velocity, both in free solution and through a bed of chromatographic media, is proportional to the potential applied. In order to achieve greater migration velocities, it is necessary to apply higher potentials.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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