Frederick Banting realized that this procedure would destroy the trypsin-secreting cells but not the insulin. Once the trypsin-secreting cells had died, insulin could be extracted from the islets of Langerhans. Banting discussed this approach with J. J. R. Macleod, Professor of Physiology at the University of Toronto. Macleod provided experimental facilities and the assistance of one of his students, Charles Best. Banting and Best, with the assistance of biochemist James Collip, began the production of insulin by this means. As the experiments proceeded, the required quantities could no longer be obtained by performing surgery on living dogs. In November 1921, Banting hit
Charles Best (medical scientist) ignoring Best and Collip. Banting chose to share half of the prize money with Best. The key contribution by Collip was recognised in the Nobel speech of McLeod, who also gave one-half of his prize money to Collip. Best succeeded Macleod as professor of physiology at University of Toronto in 1929. During World War II he was influential in establishing a Canadian program for securing and using dried human blood serum. In his later years, he was an adviser to the Medical Research Committee of the United Nations World Health Organization. Best was elected a foreign member of the Royal