Question

How is the separated DNA visualised and extracted for use in recombinant technology ?

Answer 1

The separated DNA fragments can be visualised only after staining the DNA with a compound known as ethidium bromide followed by exposure to UV radiation. We can see bright orange coloured bands of DNA in a ethidium bromide stained gel exposed to UV light.

The separated bands of DNA are cut out from the agarose gel and extracted from the gel piece. This step is known as elution. The DNA fragments purified in this way are used in constructing recombinant DNA by joining them with cloning vectors.