Whose discovery was insulin?

In 1921 and 1922 Frederick Banting and Charles Best, working in the laboratory of John Macleod at the University of Toronto, isolated the hormone insulin from the pancreas and showed it could control blood sugar. The biochemist James Collip helped purify the extract so it could be safely given to patients. In early 1922 a young diabetic patient named Leonard Thompson became one of the first people successfully treated, transforming a once fatal disease into a manageable condition. Banting and Macleod received the Nobel Prize in 1923, and Banting shared his award with Best. The discovery has saved countless lives.