Answer
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
It is not permissible to offer blood donation for money. This is pure selling blood which is not allowed in Islam.
Answering your question, Dr. Muhammad Salama, PhD, Islamic Studies in English, Associate Professor at the Faculty of Islamic Sciences al-Madinah International University (Mediu), states:
There is an agreement among Muslim jurists on the impermissibility of selling blood. The Quran explicitly declares {Forbidden to you is [the consumption of] carrion, and blood…} (Al-Ma’idah 5:3)
The Messenger of Allah (peace be upon him) sets a rule that dictates “When Allah forbids people to eat something, He forbids its price for them as well.”
Narrated Ibn Abbas:
I saw the Messenger of Allah sitting neat the Black stone (or at a corner of the Ka`bah). He said: He (the Prophet) raised his eyes towards the heaven, and laughed, and he said: May Allah curse the Jews! He said this three times. Allah declared unlawful for them the fats (of the animals which died a natural death); they sold them and they enjoyed the price they received for them. When Allah declared eating of thing forbidden for the people, He declares it price also forbidden for them.” (Abu Dawud)
There is another prophetic injunction that forbids the price of blood.
Narrated Awn ibn Abu Juhaifah:
My father bought a slave who practiced the profession of cupping. (My father broke the slave’s instruments of cupping). I asked my father why he had done so. He replied, “The Prophet forbade the acceptance of the price of a dog or blood, and also forbade the profession of tattooing, getting tattooed and receiving or giving Riba, (usury), and cursed the picture-makers.” (Al-Bukhari)
Based on this, it is not permissible to offer blood donation for money. This is pure selling blood which is not allowed in Islam.
Almighty Allah knows best.