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Ethidium Bromide - (Aug/30/2007 )

Does anyone know at what wavelength EtBr will absorb? or will it flouresence? (after binding to RNA so I can measure the amount of RNA)



The lab rat

has a good protocol, basically in the presence of EtBr nucleic acids (DNA/RNA) excited at 546 nm, will emit light at 590 nm.

So you need a Fluorometer

sadly it wont distiguish between RNA /DNA

Most dyes have this problem but Invitrogen now sell there Ribogreen with DNAse so that you can digest away the DNA first



Out of curiosity...
Have you isolated RNA? If so, are you worried about DNA contamination? If you've extracted RNA (using a kit or phenol:choloroform), you can use absorbance at 260nm to quantitate RNA.