Bio-Rad PureZOL™ RNA Isolation Reagent User Manual
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Problem
Possible Cause
Recommended Solution
Genomic DNA
Phase separation not
Make sure that centrifugation
contamination
performed at the right
step is performed at 4°C
(continued)
temperature
following the addition of
chloroform in order to
achieve complete separation
of the phases
Insufficient amount of
Scale up the amount of
PureZOL used for
PureZOL used according to
sample lysis and
sample size. Sample volume
homogenization
should not exceed 10% of
the PureZOL reagent used
for homogenization.
RNA
Starting material is
After the sample disruption
contamination
high in fat, proteins,
step, centrifuge the lysate at
with extracellular
or polysaccharides
12,000 x g for 10 minutes at
material
4°C to pellet any debris.
Transfer the lysate into a
new RNase-free tube, leaving
behind the pellet. This
should be done before
adding the chloroform.
Section 7
Reference
Chomczynski P and Sacchi N, Single-step method of RNA isolation
by acid guanidinium thiocyanate-phenol-chloroform extraction, Anal
Biochem 162, 156–159 (1987)
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