Physical Properties of the Ampholytes

When using an ultraviolet photometer for recording purposes, the disturbance resulting from this absorption at 280 nm is rather small in normal experiments, wherein the average concentration of ampholytes is 1 %. However, the disturbances can be severe for low protein contents and high concentrations of ampholytes. If it is desired to evaluate column experiments quantitatively by photometry at 280 nm, it may be necessary to make corrections for this absorption. These can be made by running one control experiment without protein. 

The linear part of the pH-gradient terminates at about pH 3.5 on the acid side and about 9.5 on the basic side. Toward the ends of the gradient, the number of different ampholyte molecules diminishes. The buffering capacity therefore becomes low there. However, in these pH ranges there are other good carrier ampholytes available. By adding, for exam- 

When working far from the neutral point, it is necessary to make sure that this electrolytic vacuum is filled. If 10% of the total amount of carrier ampholytes is added in the form of supplementary carrier ampholytes from the fraction pH 6-8, this addition bridges the gap near the electrode. No low conductivity water zone is formed and a reasonable field strength is obtained in all parts of the system. 

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