Question

What is the trailing ion in the stacking event of SDS-PAGE? What is the leading ion?

Answer 1

In SDS-PAGE, the trailing ion is SDS, a negatively charged detergent that denatures proteins, and the leading ion is the positively charged ion from the buffer solution.

Step-by-step explanation:

In SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis), the trailing ion is the negatively charged SDS (sodium dodecyl sulfate) molecules. SDS is a detergent that denatures proteins and masks their native charges, allowing them to be separated based on size by gel electrophoresis. The leading ion in the stacking event of SDS-PAGE is the positively charged ion from the buffer solution used in the gel electrophoresis.

Answer 2

In SDS-PAGE, chloride ion (Cl-) is the trailing ion, and the glycinate ion is the leading ion. Proteins are separated based on molecular weight due to the uniform negative charge provided by SDS.

Step-by-step explanation:

In SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis), proteins are separated based on their molecular weight. The trailing ion typically in SDS-PAGE is chloride ion (Cl-), as it moves behind the proteins in the gel matrix. On the other hand, the leading ion is the glycinate ion, which moves ahead of the proteins during the electrophoresis process.

Since SDS denatures proteins and masks their native charges, providing them with a uniform negative charge proportional to their size, proteins in SDS-PAGE are separated solely based on their molecular weight when an electric current is applied.