Bio-Rad PureZOL™ RNA Isolation Reagent - Manual (Page 15)

Problem Possible Cause Recommended Solution
Low yield the pellet. If necessary,
(continued) incubate the resuspended
pellet for 10 minutes at
55–60°C and then pipet up
and down
Low amount of When isolating RNA from
starting material small sample amounts,
homogenize the sample in
0.8 ml of PureZOL. Use
glycogen as an RNA carrier
by adding 5 µl of a 20
mg/ml glycogen solution
(not provided) to the
aqueous phase before
precipitation with isopropyl
alcohol. Carry out
precipitation for 30 minutes
at 4°C
The solution used to A260/A280 may vary based
dilute the RNA for on the pH of the solution
spectrophotometric used todilute RNA samples.
reading has a low To get more accurate and
consistent A260 and A280
values, dilute your RNA
samples with a solution that
has a pH within the range
6.5 to 8.5
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