using fluorescent dyes is tricky (1) they might detach from the vesicles (or you might have excess of free dye, not removed) and you might be misled by your analysis (2) dye might change properties/distribution of the vesicles (3) this kind of analysis is not sensitive enough, you'll need a lot of dye to detect the signal. So- worth trying, but not easy. Use of 32P or loading exosomes with nucleotide tracer (that could be measured by qPCR) enables quantification and max sensitivity

Dear Jana Muronova,

It is up to your dye selection. A dye like PKH may form some nanomicelle-like structures, which are confusing and are not distinguished from labeled-exosomes!

Therefore, It is better to use some purification steps (sucrose density gradient, etc.) to get rid of nanomicelle-like structures or use some labeling strategies (Commercial labeled Antibodies or Lightning-Link Technology from Expedeon (Some labels like: Europium, HRP, ALP, etc.)) in order to label your desired antibodies (Anti-CD9, Anti-CD63, Anti-CD81, Anti-TSG101, etc.) towards direct detection of exosomes in the cells or your tissue sections.

Good Luck

Mehdi

Hi Jana,

I am sorry for not seeing your question before. We do have a product that might be of interest to you. Indeed, this product utilize a combination of a FLARE (FLuorescence Activating Response Element) protein tag together with a pro-fluorophore dye. Neither the protein or dye fluoresce in isolation. When the protein binds to the dye, it causes a change in structure which results in fluorescence. The dye and protein form an unstable bond with continuous turnover of the dye. This results in sustained fluorescence without the levels of photo-bleaching associated with fluorescent proteins. This allows ExoFLAREs™ (the name of our product) to be monitored for extensive periods to allow tracking of movement of dyes.

Let me know if you are interested in learning more about it!

Julia