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High OD ratio from DNA Maxi Prep - (Jan/09/2008 )

After a maxi prep, I checked the OD.

3 pellets were resuspended in 300uL of EB each and the other 3 were resuspended in 300uL of sterile H2O. So each totals to ~900uL.

I used 5uL DNA in 95uL H2O.

EB= 260 reading of .781 and 280 reading of .305
H2O= 260 reading of .905 and 280 reading of .353

What would cause this high ratio? And is this good or bad?

Thanks.

-JatGenetics-

you still have some contaminations.
it xould be interesting to have the OD230 value too.

At first, re pellet your DNA, do extensive 70%ethanolwash, dry efficiently the pellet (sensitive step) resuspend and recheck respective od.
if contamination still occurs, trat with proteinase K and RNAse A, and do a phenol chloroform extraction.

-fred_33-