Blood Bank

 is a quest that can be obtained within the Commonwealth, in Fallout 4..

Synopsis
The scribes on board the Prydwen are in need of viable blood samples across the Commonwealth for use in their experiments. Get on it, soldier!

Walkthrough
Speaking with Scribe Neriah, will reveal that she is in need of viable blood samples from a variety of life across the Commonwealth wastes, for use in her experiments. For every sample brought back to her, she will reward the Sole Survivor with a small amount of bottlecaps. This quest remains active so long as the Sole Survivor remains in good graces with the Brotherhood of Steel, and can be completed an indefinite number of times for an indefinite number of bottlecaps.