Answered by Shaykh Faraz A. Khan
Question: I am in the medical profession, and I deal with plasma and serum. Plasma is basically blood without the red blood cells, and because the red blood cells make blood red, plasma is yellow. Serum is plasma without clotting factors and is also yellow. Sometimes plasma or serum splashes on my clothes. Is it considered blood and therefore najas, or is it tahir?
Answer: Assalamu alaikum wa rahmatullah,
I pray this finds you in the best of health states.
Blood that has flowed is certainly filthy (najis). [Shurunbulali, Maraqi al-Falah]
As for plasma or serum, the default ruling of blood would seem to apply. And Allah knows best.
Checked & Approved by Faraz Rabbani