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acridine orange - (Jan/20/2011 )

When i fix the biofilms with glutaraldehyde and stain it with acridine orange, i expect it to turn red but in some biofilm it turns green. why is this so? what makes the color change?

-tezuka-

Acridine orange is a metachromatic dye -- when it intercalates with DNA it fluoresces green (525nm), and when it interacts with RNA (by electrostatic attraction) it fluoresces red (>630nm).

-HomeBrew-

HomeBrew on Thu Jan 20 14:59:13 2011 said:


Acridine orange is a metachromatic dye -- when it intercalates with DNA it fluoresces green (525nm), and when it interacts with RNA (by electrostatic attraction) it fluoresces red (>630nm).

yup, green but only when it's bound to double-stranded DNA....red for SS DNA so we can also use it as a measure of DNA denaturation or fragmentation in cells...

-casandra-