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ISOLATE
RNA Kits
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a. hints anD tips
1. Working with rna
An RNase free environment is essential when working with RNA samples. In the
laboratory, obtaining full length, high quality RNA often proves to be a daunting task.
There are two main reasons for RNA degradation during RNA analysis. Firstly, RNA,
by its very structure, is inherently weaker than DNA. RNA is made up of ribose units,
which have a highly reactive hydroxyl group on C2 that takes part in RNA-mediated
enzymatic events. This makes RNA more chemically labile than DNA. RNA is also
more prone to heat degradation than DNA. Secondly, enzymes that degrade RNA,
ribonucleases (RNases) are so ubiquitous and hardy that getting rid of them often
proves to be nearly impossible. For example, autoclaving a solution containing bacteria
will destroy the bacterial cells, but not the RNases released from the cells.
2. sources of rnase
•
Skin: The presence of RNases on human skin surfaces has been well
documented. RNase contamination through this source is very easy to
acquire and spread if tubes, pipette tips, bench tops, etc. are touched with
bare hands.
•
Dust: Dust particles floating in the air often harbor bacteria or mold. The
RNases from these microorganisms get deposited wherever the dust settles.
This includes lab equipment, open bottles, etc.
•
Reagents: If the reagents used for RNA analysis are not certified to be RNase
free, there is a good chance that some of the contamination will come from
this source. Reagents can also become contaminated in the lab itself if proper
care is not taken.
•
Samples: RNase contamination can come from the samples themselves as
tissues and cells contain endogenous RNases.