How can you easily identify nucleic acids?

1 Answer
Feb 7, 2018

By using the Dishe's diphenylamine test...


Diphenylamine is used to test for nitrates:

However, it can also react with the Deoxyribose sugar component of DNA:

When a sample is boiled with a strong acid, the resulting depurination of any DNA present, and the subsequent dehydration of the 2D-Deoxyribose sugar produces highly reactive ω-hydroxylevulinylaldehyde . (This reaction is not specific for DNA, but for 2-Deoxypentoses.)

In an acidic solution, the ω-hydroxylevulinylaldehyde reacts with diphenylamine to produce a blue-coloured complex that absorbs at 595 nm.

Reaction mechanism:


If RNA is present, the result will turn Green...