"On Hoppe-Seyler's suggestion, Miescher changed to examining leucocytes and obtained the cells for his experiments from the pus on fresh surgical bandages, which he collected from the nearby surgical clinic in Tübingen. In pus, he found the ideal base material for his analyses, and its "histological purity" allowed him to achieve the most complete purification of the chemical building blocks that constitute cells (Miescher, 1869a)."

"Nonetheless, he worked on and discovered that sperm cells proved to be an ideal source material for the isolation of large quantities of very pure nuclein (Miescher, 1871c and Miescher, 1874b). Miescher chose these cells due to their simple composition with their heads comprised almost exclusively of a nucleus (Miescher, 1872a). Finally, he saw a possibility of obtaining sufficient amounts of nuclein to perform the exhaustive quantitative experiments he had already intended to do in Tübingen."