Pendant of insulin in 1.2 mm silver wire. The two protein threads, A & B, are enamelled yellow and red respectively.

Insulin is a hormone which lowers blood sugar levels. Sir Frederick Banting and John McLeod were awarded the Nobel Prize in Physiology or Medicine 1923 for the discovery of insulin. The Nobel Prize in Chemistry 1958 was awarded to Frederick Sanger for his work on the insulin structure, a discovery that was fundamental to the production of synthetic insulin.