What is the common use of polyacrylamide electrophoresis (P.A.G.E)?

Polyacrylamide gel electrophoresis (PAGE) is widely recognized for its effectiveness in separating proteins based on their size and charge. The technique involves using a polyacrylamide gel, which creates a matrix that allows for the movement of molecules, such as proteins and nucleic acids, when an electric current is applied.

When it comes to proteins, PAGE can separate them according to their molecular weight. The smaller proteins migrate faster through the gel, while larger proteins face more resistance and move more slowly. This size-based separation is crucial in various applications, including protein characterization, purity assessment, and determining molecular weight.

Additionally, PAGE can also be applied to nucleic acids, such as DNA and RNA, particularly when used in denaturing conditions that facilitate the separation based on size rather than shape. Therefore, it is ideal for distinguishing between different nucleic acid fragments.

Although other types of electrophoresis might focus specifically on lipids or small peptides, PAGE is primarily associated with the separation of proteins and nucleic acids, making this choice the most accurate for the given question.