Electrophoresis Capillary, Gel, and Other Forms

We recall by reference to Eq. 5.61 that the maximum number of separable peaks (the peak capacity) is —0.25 N1/2, which, with N from Eq. 8.6, yields 

This equation shows that nc increases with the square root of the ratio of structuring energy -A/icxt to dissipating thermal energy 9tT. 

We noted before that some fields are not used in static (5c) separations because the forces they generate are so weak. We see that a weak force, -dfixt/dx, leads to a small structuring energy -AfMx which is inadequate to provide values of N or nc large enough for practical use. 

In the following pages we describe several practical Sc techniques. We then evaluate the potential magnitude of N and ne for these systems. This evaluation will provide a rough comparison between the Sc methods and will show their strength relative to chromatography, where N is a well-known measure of separation efficiency. 

In electrophoresis, an electrical field causes the differential transport of charged species. Many experimental variants exist, giving the method particular versatility in the analysis of biological materials [2-6]. 

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