What did sir ernst chain and howard florey develop?

Sir Ernst Chain and Howard Florey developed a method for the mass production of penicillin, the first widely used antibiotic. Their work in the early 1940s demonstrated penicillin's effectiveness in treating bacterial infections, which significantly impacted medicine and surgery. This collaboration ultimately led to the successful production and distribution of penicillin during World War II, saving countless lives. Their contributions earned them and Alexander Fleming the Nobel Prize in Physiology or Medicine in 1945.