Improved detection of amylase activity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with copolymerized starch

An improved method, based on sodium dodecyl sulfate-polyacrylamide gel elec trophoresis (SDS-PAGE) for detection of amylase activity is described. This method will allow better characterization of certain amylases than that ob tained by the Davis technique. The main features of the technique are: (i) identification of amylase bands and molecular mass determination are possib le in the same gel; (ii) the hydrolysis of copolymerized substrate during e lectrophoretic separation is prevented using very low temperatures instead of inactivating agents such as chelating agents; and (iii) the technique is applicable to reveal amylase activity in a wide range of biological sample s. The method is not useful for enzymes sensitive to SDS and for high molec ular mass amylases.