For PBMC isolation, 5-10 ml of blood would be ideal. You can refer to this document (https://www.cedars-sinai.org/content/dam/cedars-sinai/research/documents/biomanufacturing/blood-collection-for-cryopreservation-and-shipment.pdf)

Hope it helps you.

Hello Pratibha Banerjee

You can get approximately 1.5 x 10^6 PBMCs from 1ml of blood. The final yield of cells will also depend on the PBMC isolation technique. So, 8-10ml of blood should be enough to do RNA extraction from PBMCs.

Best.

Thank you @ Jatin and Malcolm but what can be the least amount of blood? Example: Can 2ml of whole blood will do?

It depends on your experience. I recommend you go for 5ml if you are not an expert in this field. As I mentioned earlier the final yield of cells will also depend on the PBMC isolation technique.

I think 2ml will be a little less. Instead try with 5ml. It will definitely yield more cells.

thank you , will try then