How did Banting's method lead to the discovery of insulin?
My method was simple: identify a practical goal and work backward through experimentation. The goal was to isolate the pancreatic secretion that controlled blood sugar. I read a paper by Moses Barron about pancreatic stones that caused atrophy of the enzyme-producing cells but left the islets intact. That gave me the idea to ligate the pancreatic ducts in dogs. After the enzyme cells degenerated, we ground up the remaining tissue, filtered it, and injected the extract into diabetic dogs. It worked. We didn't waste time on elaborate theories—we just tried it and saw what happened. The proof is in the patient. Later, we collaborated with biochemist James Collip to purify the extract for human use. This hands-on, trial-and-error approach, combined with urgency, is what made the discovery possible. A good experiment is worth a thousand opinions.
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