Bio-Rad Aurum™ Total RNA Fatty and Fibrous Tissue Kit - Manual (Page 33)

Problem Possible Cause Recommended Solution
RNA is degraded Frozen tissue samples Add PureZOL directly to
(continued) were allowed to thaw or frozen samples before
sit at room temperature they thaw. Do not let
starting materials sit at
room temperature
Cells grown in either Cells grown in monolayer:
monolayer or aspirate the growth
suspension were medium and then add
washed prior to PureZOL directly to the
lysis with PureZOL plate. No trypsinization is
necessary
Cells grown in
suspension: pellet the
cells and aspirate growth
medium, then add
PureZOL directly to the
pellet
Starting tissue sample Make sure that starting
was not immediately material is immediately
frozen, or had gone processed following
through several dissection. Alternatively
freeze-thaw cycles the starting material must
before RNA be immediately frozen
purification was after dissection. Once
performed frozen, do not subject
starting material to
freeze-thaw cycles
Low RNA A
260
/A
280
Lysate was not Make sure to incubate
ratio incubated at room the lysate after the
temperature for disruption step for
5 min after the 5 min at room
disruption step temperature to allow
(see step 3 in complete dissociation of
protocol) nucleoprotein complexes
Ethanol contamination Prior to eluting the RNA,
of the eluate make sure to perform the
purge spin step (see step
16 in spin protocol) to
remove residual ethanol
in the wash solution
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