Agarose Gel Electrophoresis- Definition, Principle, Parts, Steps, Applications


Agarose gel electrophoresis is a widely used technique in molecular biology, biochemistry, genetics, and clinical chemistry. It is used to separate and analyze different types of molecules, such as DNA, RNA, and proteins, based on their size and charge.

Agarose is a natural polysaccharide extracted from seaweed. It forms a gel-like matrix when dissolved in a buffer solution and heated. The gel has pores of varying sizes that allow the movement of molecules under the influence of an electric field. The molecules are loaded into wells at one end of the gel and migrate towards the opposite end according to their size and charge. Smaller and more negatively charged molecules move faster and farther than larger and less negatively charged molecules.

Agarose gel electrophoresis can be used for various purposes, such as:

  • Estimating the size of DNA or RNA fragments by comparing them with known standards
  • Analyzing the products of polymerase chain reaction (PCR), such as in genetic testing or forensic science
  • Separating DNA fragments after digestion with restriction enzymes, such as in cloning or mapping
  • Separating RNA molecules before hybridization with probes, such as in northern blotting
  • Separating proteins by their charge or molecular weight, such as in western blotting or immunoelectrophoresis

Agarose gel electrophoresis is a simple, inexpensive, and versatile method that can provide valuable information about the structure and function of biomolecules. It can also be combined with other techniques, such as staining, blotting, or sequencing, to enhance the detection and analysis of the molecules. In this article, we will discuss the principle, requirements, steps, applications, and advantages and disadvantages of agarose gel electrophoresis.