Chromosomal DNA carry-over in plasmid mini-preps

martin LEACH leach at
Mon Feb 10 22:38:59 EST 1997

I'd check the neutralization solution (potassium acetate) used following the
alkaine lysis.

maybe the ph or the concentration is off.....

usually the large 'gunk' is precipitated out during/following neutralization.

Michael Mangan (mmangan at wrote:
: Hello Netters,

: I have a very annoying problem with the carryover of chromosomal 
: DNA in alkaline lysis minipreps, of midrange (60 kb) plasmids.  
: Can anyone out there

: a) tell me what am I doing that is giving me this problem ?

: b) offer any solutions ?

I assume the lysis is going well.....does the solution still look viscous
following neutralization?? do you have much white ppt??


: Thanks in advance   

.....          Martin Leach                Email:leach at
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