Purified Saccharomyces cerevisiae yeast transfer RNA is suitable as a coprecipitant in nucleic acid precipitations. It cannot be used in reactions inhibited by exogenous RNA, and it is the most inexpensive source of a high-quality coprecipitant. This transfer RNA preparation is supplied in one tube containing 0.5 mL at a concentration of 5 mg/mL in diethyl pyrocarbonate-treated distilled water. It is typically used at a working concentration of 10–20 µg/mL.

What is a Coprecipitant?
Coprecipitants are inert substances used to aid recovery of nucleic acids during alcohol precipitations. While they can be used for precipitating large amounts of nucleic acids, they are essential for quantitative recovery of small amounts of nucleic acids in dilute solutions. Often, the use of such molecules is desirable for no other reason but visualization of the pelleted precipitate after centrifugation.