User Manual

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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