Hi everyone,
I've recently isolated RNA using Qiagen kit (only obtaining RNA >200 nts) and ran the samples on High Sensitivity Screentape. The RINs are quite good, between 7.5 and 8.5, and 28S peaks higher than 18S peaks. There seems to be some smearing so quality could be a bit better but the results indicate the quality is decent.
Next I sent these samples to a sequencing facility. Unfortunately the package got stuck at customs and was underway for about 55 hours, much longer than expected. Nonetheless the people at the facility informed me that the samples were still frozen and on dry ice when they opened the package so I thought I was safe.
However their QC, using a BioAnalyzer showed much different results than mine, with RINs dropping to 5.3 (where I measured them at 8). When I rerun the samples on the Tapestation I get similar results as before, so still decent quality (RINs around 8).
The people at the facility suggest it might be because of the different machines since the samples were frozen when they arrived so likely nothing bad happened during transit.
However when I compare the electropherograms from TS and BA they look different (this is also true for the gel pictures), which is not something I would expect to arise from a difference in hardware since, as I understand it, the peaks in the electropherogram are what the RIN is based on. I would attribute such to degradation somewhere along the way but my experience with RNA is not extensive.
Has anyone here come across a difference like this? Could it indeed be because of the different machines? Or could the samples have degraded during transit after all? Many thanks for your input!
Here's a picture with snapshots from both ScreenTape and Bioanalyzer
I've recently isolated RNA using Qiagen kit (only obtaining RNA >200 nts) and ran the samples on High Sensitivity Screentape. The RINs are quite good, between 7.5 and 8.5, and 28S peaks higher than 18S peaks. There seems to be some smearing so quality could be a bit better but the results indicate the quality is decent.
Next I sent these samples to a sequencing facility. Unfortunately the package got stuck at customs and was underway for about 55 hours, much longer than expected. Nonetheless the people at the facility informed me that the samples were still frozen and on dry ice when they opened the package so I thought I was safe.
However their QC, using a BioAnalyzer showed much different results than mine, with RINs dropping to 5.3 (where I measured them at 8). When I rerun the samples on the Tapestation I get similar results as before, so still decent quality (RINs around 8).
The people at the facility suggest it might be because of the different machines since the samples were frozen when they arrived so likely nothing bad happened during transit.
However when I compare the electropherograms from TS and BA they look different (this is also true for the gel pictures), which is not something I would expect to arise from a difference in hardware since, as I understand it, the peaks in the electropherogram are what the RIN is based on. I would attribute such to degradation somewhere along the way but my experience with RNA is not extensive.
Has anyone here come across a difference like this? Could it indeed be because of the different machines? Or could the samples have degraded during transit after all? Many thanks for your input!
Here's a picture with snapshots from both ScreenTape and Bioanalyzer
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