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DNA precipitated out in digest reaction - (Feb/04/2005 )

I was trying to enzyme digest some DNA last night. Only to find little chunks (DNA) in the tubes this morning. I assume its my DNA. Does anyone know where i screwed up? Thank you


first of all, does your enzymes show a star activity (restriction activity over related sequences)?
did you mind about :
# High glycerol concentration [>5% v/v]
# High units to µg of DNA ratio [Varies with each enzyme, usually >100 units/µg]
# Low ionic strength [<25 mM]
# High pH [>pH 8.0]
# Presence of organic solvents [DMSO, ethanol, ethylene glycol, dimethylacetamide, dimethylformamide, sulphalane]

for complete information see neb related page at

try an other experiment on only two hours to see if the dna become cutted in the same way as in your first experiment.

keep us informed and never give up wink.gif