Dorothy Hodgkin developed the first accurate three-dimensional structure of insulin in 1969.
Hodgkin used X-ray crystallography, a method that analyzes how crystals diffract X-rays, to determine molecular structures. Insulin was especially challenging because it is a large protein, so solving its structure required decades of work, improved instruments and extensive calculations.
Her research also established structures for penicillin and vitamin B12. She received the 1964 Nobel Prize in Chemistry for her determinations of important biochemical substances using X-ray techniques.
A common mix-up is to credit Hodgkin with discovering insulin itself. Insulin had been isolated earlier by Frederick Banting, Charles Best and colleagues in the 1920s. Hodgkin’s achievement was determining its atomic arrangement, which advanced understanding of how the hormone functions.