heating RNA in water - (Nov/17/2008 )
I have been trying to find literature about RNA stability in water after heating at 70C. We use the PicoPure isolation kit which has an elution buffer of water (volume typically ~11 uL). Concentrations of RNA in samples are typically 10 ng/uL by NanoDrop and we use the Bioanalyzer Pico Chips to evaulate our samples. We typically only heat denature our samples once as per Agilents instructions and everything has been looking good. But this is usually only done once and proceed with downstream applications. We ran into an issue recently when a sample was re-analyzed (thawed from -80 on ice, then heated to 70 for 2 min, placed on ice) and resulted in a completely different profile. I suspect that because the sample is in water without any buffering that the repeated heated was bad and the reason for denaturing of the sample. But can not find any references any where to back up the theory. Was hoping that some more knowledgable person out there could help.
Water can cause acid hydrolysis of DNA and RNA in solution. For this reason most people use a buffered (e.g. Tris or TE/TLE) for resuspending their RNA and DNA.