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phenol problem - (Dec/08/2005 )

hi all
is oxidized phenol useful for phenol/chloroform extraction or not?
I have phenol crystals ,when heated become liquid but it is pink ,is that useful for extraction or not?


The oxidation products are quinones, a wide variety of phenolic coupling compounds and diacids. Quinones are a, b-unsaturated ketones that are capable of reacting with primary amines. The reaction of quinones with multiple amines can form stable crosslinked products. Quinones can crosslink nucleic acids and may break down phosphodiester bonds. The diacids arise from further oxidation of orthoquinone, while phenolic coupling products result from phenoxide radicals. Quinones are faintly yellow. Phenolic coupling reaction compounds are intense yellow or pink/red. (1985 BRL Focus 7(2):12.)


funny you should post ythis today, because i just did a DNA extraction using phenol/chloroform and it was slightly pink (oxidised). my DNA prep failed and since i've done it so many times before all i can think of was that it was cos of the oxidised phenol. i now also know the in-depth chemistry of it. thanks tfitzwater.