Hi Subodh,

You might find a positive answer to your request in the article of Q. Ge at al. published in Molecules (2014, 19:1568-75), entitled “miRNA in Plasma Exosome is Stable under Different Storage Conditions”. Thus the miRNA concentration was measured through individual specific miRNAs (miR-16, miR-24, miR-451, and miR-181a) by qPCR and these miRNA expression levels in exosomes and plasma. The results shown that these four serum/plasma abundant miRNAs are quite stable in exosomes when kept at -20 for up to 3-5 years.

Best wishes,

Ilya

Thanks IIya for quick reply. I will go through that article, hoping it will be useful for us.

Hi Suboth,

miRNA are very stable in serum/plasma in conditions such as 10 free-thaw cycles and even boiling (Cortez & Calin, Expert Opin. Biol. Ther. (2009) 9(6):703-711). You SHOULD be able to extract miRNA from those samples.

As IIya said, you could do qPCR on those miRs, however, be wary that miR-451a and miR-16, which are highly abundant in serum, are sensitive to haemolysis. I am not sure which other miRs could serve as a positive control. perhaps miR-103?

The MI   RNA  remain stable for long time even more than 5 -6 years  while, avoiding repeated   thawing and freezing may induce the degradation of RNA

Thank you everyone for your valuable suggestions.

Hello Subodh,

Hope your research is coming up good. miRNAs, owing to their size, have a long "shelf lilfe" when stored in -80.

Just be careful in terms of how was serum sample extracted, as it has an influence on the total miRNA extracted.

Warm regards,

Venk