Question

What is elution in the process of separation of DNA fragments?

Answer 1

Hint: Electrophoresis is the process of separating DNA fragments. Elution is the process of separating and extracting a material from another. Ethidium dye is used to visualize the DNA fragments. DNA fragments are only visible in UV radiation.

Complete answer:
Electrophoresis is the process by which DNA fragments separate. When the electric field is applied across two electrodes (cathode and anode) that are totally submerged in a colloidal solution, the particles tend to move towards one or the other electrode. Gel electrophoresis is used to separate DNA, macromolecules such as RNA and proteins based on their size and charge. Electric current is supplied in the gel to separate DNA fragments. This process is called electrophoresis.
 The process of electrophoresis is an elution which is generally a process of extracting one material from another by washing with a solvent. It helps in the extraction of sample material into the solution so it can be tested easily. When the sample DNA fragments are loaded on an agarose gel, being negatively charged it moves towards the anode.
Ethidium bromide dye is used to stain the DNA fragment and exposed to UV radiation. DNA bands are then separated and cut out from the agarose gel. After that these bands are extracted from the gel piece. This step is known as elution. The DNA extracted from elution is amplified by PCR and can be used for several techniques like DNA fingerprinting etc.

Note: Electrophoresis has many applications such as estimation of the DNA molecule, analysis of PCR products. Separation of restricted genomic DNA and RNA, conformation of newly isolated DNA, separation of most fragments of DNA, in forensic science, in determining molecular weight of protein, Medical research, agriculture, etc. It plays a very important role in genetic engineering.