How was penicillin developed?

Alexander Fleming in 1928 discovered that an unknown mould had grown onto a petri dish containing bacteria and killed it.

He tested the mould and found out it was an antibiotic (Penicillin).

He tested it on bacteria in the lab but not on humans and published his findings in 1929 but didn't have the facilities or the support to develop and test his theory.

In the 1930's Florey and Chain read his paper and in 1939 set up a skilled research team to develop Penicillin, and asked the British government for funding.

They carried out scientific experiments on mice to test that it worked and had to use household objects such as a hand pump to slowly gather a few grams of pure penicillin.

The growing number of casualties in WW2 meant it was needed more urgently and german bombing meant mass production in Britain would always be a problem.

In June 1941 Florey went to the USA to try and interest drug companies out there. When the USA joined the war in December 1941 they became interested.

In 1942 the US government gave $80 million to 4 drug companies to find a way to mass produce penicillin.

Scientists at Pfizer in NYC used an old ice cream freezer to develop a method of freeze drying that was eventually used for mass scale production.

After the war penicillin became available for civilian use.