Hi, 

I islolated exosomes by ultracentrifugation and then extract miRNA with mir-Vana extraction kit (ambion). If you have interest in the protocol I can resend. Then I made a RT-PCR to verify that had miRNA isolated and the result was positive (with preamplification)

Best regards

This kit will help you.

Plasma/Serum Circulating and Exosomal RNA Purification Mini Kit (Slurry Format)

(Cat# 51000) by Norgen Biotek. 

It was verified in "Prognostic serum miRNA biomarkers associated with Alzheimer’s disease shows concordance with neuropsychological and neuroimaging assessment." by Cheng 2014.

I agree with Sercan the kit will help you. For more information about different techniques to extract RNA from exosomes you can also refer to this paper:

Optimizing the purification and analysis

of miRNAs from urinary exosomes  By

Sarath Kiran Channavajjhala, Marzia Rossato,..

the paper is for extracting exosomal miRNA from urine but the source of exosome does not interfere and some of the protocols described in it can be used for RNA too. In any case if you need help for extracting exosome I can help you.

ExoQuick gets you your exosomes, but not your RNA.  You have to lyse the exos and isolate the RNA.  I am using mirvana microRNA kit from Ambion.  Works for me!

Hi, 

I islolated exosomes by ultracentrifugation and then extract miRNA with mir-Vana extraction kit (ambion). If you have interest in the protocol I can resend. Then I made a RT-PCR to verify that had miRNA isolated and the result was positive (with preamplification)

Best regards

Dear Ana Salinas,

Thanks for guidance, I would like to read this protocol, could you please send it to me ?

my email address: [email protected]

Thanks again.

Dear Sercan Ergün and Somayehsadat Ghasemi ,

Many thanks for taking your time to answer this question.

Dear Crista Ochsenfarth,

Thanks for your answer but I dont thinks so, I think ExoQuick kit gets RNA after the exosome isolation. Is it right?

No, Exoquick only precipitates the Exosomes!!!! Read the product description.

I've sent the protocol to your email.

Hi, I using miRCURY RNA Isolation Kit to extract exosomal RNA from 0. 5 ml serum and I got very low volume. Then I reduced the elution volume ( from 100 µL to 50 µL)  in order to make it more concentrated and I increased the incubation time on the column and heated the water(37c) but still get very small  RNA volume, please any advice, it will be appreciated.

Dear Ana Salinas , thanks a lot

I would recommend reading the ISEV minimal requirements paper http://www.ncbi.nlm.nih.gov/pubmed/25536934 and references therein. There is a difference between "salting out" everything in a fluid using PEG (the commercial precipitation kits) and purifying exosomes. But I don't think purity is the issue here. What are you using to assess the amount of recovered RNA? If you are expecting spectrophotometer-measurable quantities of RNA, for example, you will be disappointed even if your technique is good.

Hello Anna Salina,

I would appreciate if you can upload the protocol to your profile.

Thanks

Sharad

I would like to know about miRNA isolation from exosome from cell culture, I have used Exofree FBS to culture the cells, my question is if there will be chance for bovine RNA contamination? Please let me know.Thanks a lot in advance-Anusha

Dear anna Salina can you send an email ([email protected]) to me your detail protocol as I am also facing the same problem .thank you

Dear Ana Salinas ,

I'm currently facing issues extracting microRNAs from conditioned media. It would be greatly appreciated if you could share your protocol with me as well. Despite this thread being some what old, I really hope you get to see this request. Thanks in advance!