Hi Farhan exosomes have very low RNA yield. try the Total exosome isolation reagent, then recover RNA- eg with Total exosome RNA & protein isolation kit, and move forward with qRT-PCR or seq analysis. in some cases you can do the "blind" experiment- without analyzing RNA by spectrophotometry. its ok

I would suggest to purify your exosome without using any kit but with ultracentrifugation and gradient. the yield and purity would be better if you want to assess extracellular vesicule (EV), I don't know whether kits take in consideration all the EV possible. Also try to increase your starting quantity of medium if you can. Good luck!

 thank you for your answer. 

@ Thiaut Deschamps - i am concern on the exosome purity isolated from ultracentrifuge, as this method will precipitate all the vesicles and some unknown vesicles. 

Hi Farhan

To increase the RNA concentration I suggest the use of RNA Basic Kit HansaBioMed. The kit is designed for the purification of total RNA from pre-isolated exosomes and includes special columns which can be eluted with a low amount of volume of elution buffer (5 -15 ul) allowing to get a quite concentrated yield of exosomal RNA.