Penicillin powder, 1942, used in early clinical trials

Penicillin was isolated in 1940 by an Oxford University team led by Howard Florey (1898-1968). At first the scientists managed to produce only very small quantities of impure product – the characteristic bright yellow colour of the early penicillin was caused by an impurity. Patients had to endure painful in-jections – usually into a buttock – every three hours because the body proc-essed the drug so quickly. This powder was intended for use in early clinical trials, which proved the effectiveness of penicillin as an antibiotic.