Steady State Electrophoresis

The fundamental basis of this method is that, after electrophoresis has proceeded for a certain length of

Figure 2 Apparatus for zone electrophoresis.

time, a state known as the steady-state is reached in which no further changes to either the position or the width of the zone of the separated components occur with time. Steady-state electrophoresis involves two types of techniques, isoelectric focusing and iso-tachophoresis.

Isoelectric focusing In this technique the charged components of the sample move through the medium under the influence of an applied electric field until they ultimately reach a position in the pH gradient where their nett charge is zero and hence they do not migrate any more. This pH is their isoelectric point. The individual bands may be collected from the apparatus, and examined chemically or biologically.

This technique has very high resolving power, and may be used preparatively. It is not applicable to some compounds (proteins) that precipitate at their isoelectric point, which makes their recovery difficult.

Isotachophoresis This technique is particularly applicable to the separation of charged components with small relative molecular masses, such as some drugs and polypeptides of medical interest. In this technique all the charged components become stacked one behind the other, depending upon their electrophoretic mobilities.

To achieve a good separation of two charged components from one another by isotachophoresis, their electrophoretic mobilities must differ at least by 10%.

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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