World Wars and the AtomMedicine & Health Penicillin becomes a drug 1940Major Howard Florey and Ernst Chain's Oxford team purifies penicillin and shows it cures infected mice, leading to mass production by D-Day. ▲ MattersSaveShareTrace roots Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → Dinosaurs appear → Asteroid ends the dinosaurs → Early primates → Apes split from monkeys → Human line splits from chimpanzees → Walking upright → First stone tools → Genus Homo appears → Homo erectus → Control of fire → Habitual fire and cooking → Homo sapiens appears → Complex language → Natufian villages → Oldest known bread → Agriculture begins → Irrigation → Uruk and the first cities → Cylinder seals → Writing (cuneiform) → Babylonian mathematics → Babylonian astronomical diaries → Thales and natural philosophy → Trial and death of Socrates → Plato's Academy → Aristotle's Lyceum → Alexander's conquests → Alexandria founded → Library of Alexandria → House of Wisdom → Ibn al-Haytham's Book of Optics → Eyeglasses → Compound microscope → Microorganisms discovered → Handwashing in medicine → Germ theory of disease → Penicillin discovered → Penicillin becomes a drug Community notesLoading notes… Learn more ranked by votesDocumentnobelprize.orgThe Nobel Prize in Physiology or Medicine 1945 (Nobel Prize) ↗Editor's pickBookEric LaxThe Mold in Dr. Florey's Coat ↗Editor's pickVideoSearch on YouTubeFlorey and Chain penicillin story ↗Editor's pick