Scientist. Born in Glasgow, the son of a businessman, Todd was educated at Allan Glen's School and the University of Glasgow, before undertaking doctorates in Germany and at Oxford. He began his professional career at the University of Edinburgh (1934) but left to join the University of London (1937), before being appointed to a Chair of Chemistry in Manchester (1938). His last move was to a Chair at Cambridge, which he accepted in 1944.
Widely honoured for his work in biochemistry, which included investigation of vitamins, enzymes and the constituents of cannabis, Todd was awarded the Nobel Prize for Chemistry in 1957 and held an honorary degree from the University of Glasgow. His research brought an understanding of nucleic acids, which led directly to Crick and Watson's discovery of the helical structure of DNA in 1962.
He was knighted in 1954 and raised to the Peerage as Baron Todd of Trumpington (1962). Todd served on many government committees and, with a keen interest in international scientific affairs and policy, was elected Chairman of the British Government's Advisory Council on Scientific Policy (1952). After his retirement, he was appointed Chancellor of the University of Strathclyde (1975).
He died in Cambridge.