From ugly fish to conquer death: J J R Macleod's fish insulin research, 1922-24.

Fish insulin research had a very short heyday. Throughout most of 1922, production of insulin from livestock was difficult, erratic, and expensive. Although fish insulin was easy to extract and seemed to be a brilliant and logical solution to the shortage of insulin, collection of fish islets was a logistical nightmare. By the end of 1922, a scientist at the pharmaceutical company Eli Lilly in Indianapolis, IN, USA had developed a way to concentrate and purify insulin by isoelectric precipitation. As a result of this breakthrough, the scales began to tip heavily in favour of livestock insulin. Nevertheless, research on commercial production of fish insulin continued for another 18 months but was finally abandoned.