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First Diagnostic Test
Scientists developed chemical tests to detect the presence of sugar in the urine. The results of these tests were used to diagnose a patient with diabetes -
Discovery of Glycogen's Relation to Diabetes
Claude Bernard deduced that a sugar-forming or glycogenic, substance must be present in a liver after testing a dog's liver. Eventually, Bernard isolated pure glycogen allowing for the first linkage of glycogen to diabetes and metabolism. He discovered that glycogen is secreted by the liver.Iit supported his theory that it is the same sugar exhibited in the urine of diabetics -
Removal of Pancreas Leads to Diabetes
German physician Von Mering disproved Bernard's liver theory by finding that diabetes occurred after removing the pancreas. At this time scientists believed that an anti-diabetic substance might come from the islets of Langerhans (groups of pancreatic cells). This was reasoned because the rest of the gland was quite different and therefore would have a different function. -
Use of Insulin Is Discovered
In May of 1921, Fredrick Banting, a romanian scientist, makes a triumphant discovery of insulin by extracting substances through many trials with dogs. He gave material from islets of Langerhans to diabetic dogs and their blood sugar levels decreased. -
First Use of Insulin on a Human
A 14-year-old boy named Leonard Thompson became the first human patient to receive insulin made by Frederik Banting and Charles Best. He was injected with insulin extracts in Toronto, which was considered a fail because the results were questionable but it did end up saving his life. -
Development of Purified Injections
J.B. Collip, a visiting professor who observed Banting & Best's studies, began to develop purified injections of insulin, which were soon administered. They worked by dropping the blood glucose levels of patients. This insulin had to be injected twice daily and became part of a painful treatment course that often resulted in abscesses. News spread all over the world and lead to more advancements. -
Insulin is Manufactured Commercially
Connaught in Toronto and from Eli Lilly, of Indianapolis, IN, learned how to make the insulin and collaborated to produce insulin in the United States and Latin America. While Lilly was successful in manufacturing insulin, the Toronto team continued to struggle and by mid-July 1922 there was a severe shortage in Toronto. Lilly shipped the product and by the end of 1923, insulin was being produced commercially and used to treat diabetes in most western countries. -
Insulin was crystallized
In 1926, J.J. Abel crystallized insulin. Its composition, two chains of 51 amino acids linked by disulphide bridges, was discovered by Fredrick Sanger of Cambridge. For his work, he received the Nobel Prize in 1955. -
Protamine Zinc Insulin Introduced
There was an obvious need for a longer acting insuli, and in 1936, protamine zinc insulin was introduced -
Insulin Syringe is developed
In this decade, a uniform insulin syringe is invented which lead to more sustainable management of diabetes. Helen Free also developed the "dip-and-read" urine test which allowed instant monitoring of blood glucose levels. The life expectancy of people diagnosed with diabetes increased. -
Immunoassay Technique
The scientific investigation of diabetes was improved by the technique of immunoassay by Solomon Berson and Rosalind Yalow. Minute concentrations of insulin can be consistently measured, a huge improvement on the previous methods of the bioassay. Yalow, who survived Berson, received the Nobel Prize, knowing that their work transformed endocrinology. -
Distinction Between Two Types of Diabetes
The two major types of diabetes are recognized: Type 1 diabetes and Type 2 diabetes. This allowed people to know if the use of insulin would help their diabetes or if they had to resort to controlling diabetes with diet and exercise. -
First Testing Strips Are Created
At this time the first strips for testing blood glucose level are used. These would work by placing a drop of blood onto the strip, waiting 1 minute, then washing off the strip. After the strip was washed off, the color change would be compared to a color chart provided, allowing for rough estimates of blood glucose levels. -
Insulin Today
Today in the United States, biosynthetic human insulin is made by recombinant DNA technology, a scientific process that allows for the production of nearly unlimited quantities of human insulin. Because insulin needs vary from person to person, different types of human insulin are available. Now we are able to choose whether we want our insulin to be anywhere from rapid acting to long acting. Lastly, now we have multiple options to administer insulin ranging from insulin pen to pumps.
