Abstract
Tannic acid (TA) and proteins interacted on polyacrylamide gel after electrophoresis and formed water-insoluble complex which appeared on the gel as white and clear bands. The formation of the complex primarily depended on the pH and concentration of TA solution. The optimal pH and concentration of TA solution for complex formation on pH 4.3, 8.0 and 9.5 gels that were usually used in polyacrylamide gel electrophoresis, were established. In most proteins tested, a few micrograms per gel were detectable on the pH gels within 1 hr after electrophoresis: When Takaamylase A was localized on the gel with TA, the enzyme maintained activity in it, and the enzymatic activity was recovered in good yield from the gel. The use of staining technique in polyacrylamide gel electrophoresis is described.
