Electrophoresis—General

The widest application of electrophoresis is in separations for the isolation and purification of small amounts of compounds. The best method of referring to such separations and of comparing one system to another has been the mobility of the compounds involved. Therefore, correct mobilities are important, and anyone using electrophoresis should be familiar with the various factors influencing the mobility and know what corrections should be made. 

Consider a particle that is placed in a container of liquid, saturated with a buffer, and has a potential applied to it. The force, F, exerted on the particle is equal to the charge of the particle, Q, times the field strength, E. 

The mobility calculated in this way with equation 27-5 cannot be verified experimentally, because the negative chloride ions moving in the opposite direction from the ions have an additional retarding effect on the mobility. 

This tendency to decrease the mobility of the Ba is related directly to the ionic strength of the solution. By incorporating the Debye-Huckel equation, the following correction term is obtained  

Referring to the previous example, what is the mobility ol the ion when the other ions are considered  

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Why is agarose gel electrophoresis generally preferable to polyacrylamide gel electrophoresis ... 

Structure controlled dendritic polymers that have been studied using gel electrophoresis generally behave as mimics of either proteins or nucleic acids, and possess similar ionic groups such as -NH3 , -COO , or P04 functionality. Dendrimer structures may be widely modified as a function of their interior composition and as well as the nature of their surface groups. Depending on their structure, the influence of pH may vary dramatically for different dendrimers. 

Your schedule will dictate the length of time samples will be separated by electrophoresis. General guidelines are presented in Table E39-3. Please refer to the experiment instructions for specific requirements. 

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