DNA dyes

Jfloring at aol.com Jfloring at aol.com
Wed Aug 16 17:05:44 EST 1995


Brian D. Lanoil (lanoilb at ava.bcc.orst.edu) wrote:
>I did try it a while back, and I found little difference between SYBR 
>Green and EtBr.  In fact, there was a disadvantage that I saw--the 
>exposure times you need to use for imaging the SYBR Green-stained gel was 
>10-fold longer than for EtBr.  It is true that there is no background at 
>all, but the signal was so faint that I couldn't see it with my eye 
>alone, even at high DNA concentrations.  

I've fooled around with SYBR green I, and found it to be always BRIGHTER than
EtBr.  However, after one use, the solutions did not work very well for us,
and perhaps that's what happened to you.   Also- the filter on the camera
which is used for EtBr is not right for SYBR green, and that may also be
increasing the exposure time.  Try using a fresh solution, if you haven't
 yet.

>The main advantages I saw to SYBR green is that it does not appear to 
>interfere with restriction digestion, unlike EtBr (rest omitted)

I hadn't realized this.  Is this part of the official documentation, or an
observation you made?  
If this is indeed true, I'll use SYBR green in spite of the cost.
Cheers, 
Jeanne Loring





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