Chapter 8 - Quality control for RNA preparations

Abstract

Every laboratory application involving purified RNA requires a quality assessment of the sample, particularly the mRNA fraction. Because of the labor-intensive and costly nature of most downstream assays, it is prudent to show that the RNA template material is intact and of sufficient purity so as to maximize productivity, reproducibility, and sensitivity. In the RNA world, it’s all about quality control. Checking an RNA sample for integrity and level of purity may be accomplished in a variety of ways, some of which are also very good positive-control techniques for transcription-based assays. Of the methods delineated below, spectrophotometric analysis and examination of the electrophoretic profile of each sample should always be performed shortly after purification and, if the RNA has been stored for a while, a second aliquot should be tested just prior to use. Do not ever assume that a sample previously characterized remains intact after storage for several months, even at −80°C.