Penicillin was a serendipitous discovery. It was discovered accidentally in 1928, by a Scottish bacteriologist named Alexander Fleming.
Fleming was doing research on the staphylococci bacteria in his laboratory located at a hospital in London, St. Mary’s. During one of his experiments he placed one of the dishes holding bacteria by an open window. The wind blew in some mold, which contaminated the sample of bacteria.
Fleming could easily have just thrown away the bacteria sample, and penicillin would never have been discovered. However, the curious man decided to examine it under the microscope. He found that the mold had infected the sample but there was also a “clear zone” where the penicillium had dissolved the staphylococci bacteria. Fleming had found an anti bacterial agent!
However it remained to be seen whether the peniccillium could be made into a medicine. Early trials revealed the difficulty of making the penicillin “active” long enough in the body to kill the bacteria. Fleming looked for someone who could help him purify it. He was helped by Oxfort researchers Howard Florey, Ernst Chain, and Norman Heatley who were able to use it successfully on lab mice. (They were eventually awarded the Nobel Prize in 1945 for the field of medicine). However, it was only years later that Orvan Hess and John Bumstead were able to make medicine that was effective on people. Andrew Moyer was able to further develop the drug to allow mass production, and was named part of the National Inventors Hall of Fame.