Total ribonucleic acid (RNA) isolation is a laboratory technique used to extract all of the cellular RNA from a tissue sample. This differs from other processing methods which selectively pull out certain types of RNA. A researcher might, for example, want to inspect messenger RNA (mRNA) and could work with a sample to extract just this genetic material. There are a number of lab protocols available for total RNA isolation, using a variety of products made by scientific suppliers.
There can be a number of advantages to collecting all the cellular RNA from a tissue sample. It may yield more pure and usable information. The technique can also allow researchers to check for degradation that might cause problems with experiments. If the sample is of poor quality, the researcher can extract RNA again to get a cleaner and more useful collection of RNA. This can be important for many types of research, where poor RNA at the start causes problems with experiments down the line.
Techniques for total RNA isolation can involve a variety of chemical agents. Some focus on the use of nontoxic chemicals to reduce the risk of damage to the sample. Such chemicals also limit downstream pollution of RNA and are safer for lab workers. Labs tend to select a specific chemical and protocol to recommend to all personnel and include a detailed description of the total RNA isolation procedure in their manuals. This ensures consistency in RNA processing at the facility to yield more stable and useful results.
The process starts with preparation of a tissue sample, which can vary in size, to get it ready for treatment which chemical reagents to draw out the total RNA. Technicians consult the lab manual to determine how to handle the sample and treat it to isolate the RNA. They can use tools like electrophoresis plates to check the quality of the sample, looking for signs of degradation that might indicate a problem with the total RNA isolation process.
Researchers can conduct their own total RNA isolation or delegate this task to a lab assistant, graduate student, or similar lab worker. It is also possible to contract isolation out to other lab facilities. This may sometimes be necessary to protect the integrity of an experiment, by using a third party to generate verifiable and repeatable results. In any scientific papers based on research with the isolated RNA, the researcher needs to discuss the method used for isolation, and who performed the work.