12
Problem
Possible Cause
Possible Solution
Bacterial DNA
Excessive amount of
Determine OD
600
of
contamination
bacteria processed
culture and do not
exceed 12 OD•ml of
bacteria processed
Excessive agitation of
Do not shake or vortex
lysate
lysate after addition of
lysis solution
RNA contamination
Excessive amount of
Determine OD
600
of
bacteria processed
culture and do not
exceed 12 OD•ml of
bacteria processed
Compromised RNase
Replace kit
activity due to age or
storage conditions
Low A
260/280
Excessive amount of
Determine OD
600
of
bacteria processed
culture and do not
exceed 12 OD•ml of
bacteria processed
Incomplete suspension
Ensure that the bacterial
of bacterial pellet
pellet is completely
resuspended prior to
addition of lysis solution
Incomplete mixing of
Invert briskly 6–8 times
resuspension, lysis, and
after the addition of each
neutralization solutions
reagent; check to ensure
homogeneous mixing
Incomplete washing of
Use recommended wash
column membranes
solution volumes. Add
correct amount of ethanol
to wash solution
concentrate.
