Question

What is gel electrophoresis?

Answer 1

Hint: Gel electrophoresis is the process of employing electricity to move small molecules across a gel medium, based on the charge density of the small molecules. Molecules with a higher or more prominent electric charge move faster and farther whereas one’s which are less charged move slower. The type of gel used also influences the movement of the molecules based on its pore/mesh size.

Complete answer: Gel electrophoresis is a process of separating various small molecules based on their size and charge. Gel electrophoresis works on the principle of difference in the electric charge of molecules. Initially, a gel medium is prepared, which can be agarose or polyacrylamide. A semi-solid gel medium is required, as we need the molecules to pass through the medium at the same time not move away from their well column, a gel/semi-solid medium will enable the molecule to move at the same time not disperse entirely. Agarose is used in the case of DNA molecules because it has a greater range of separation but low resolving power, whereas acrylamide is used in case of protein separation as they have high resolving power. The gel is usually prepared using a buffer solution so that the molecules can move through the gel. Gel electrophoresis techniques have a specific setup that enables power connections and well combs. In the case of DNA molecules, we know that they are negatively charged, thus the portion near the well is the positive terminal and the portion away from the well is the negative terminal. When a current is passed through the gel, as the DNA is negatively charged, they move from the positive terminal to the negative terminal. Larger fragments of DNA/Proteins move faster and further as they have a higher negative charge. And based on this principle we can separate and identify the molecular weight of DNA and or Proteins.

Note: Gel electrophoresis is a process of separating small biomolecules such as DNA or Proteins. Gel electrophoresis used for DNA is known as Agarose DNA Electrophoresis and for proteins is known as SDS-PAGE (Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis).