Dorothy Hodgkin spent her life specialising in X-ray crystallography, a technique to determine the atomic and molecular structure of crystals. Crystalline atoms cause X-rays to diffract in specific directions from which a precise 3D picture of the crystal’s internal structure can be produced. Knowing the molecular structure of a particular substance is fundamental to many advances in chemistry, biology, and medicine.
Dorothy focused on biological and organic compounds. In 1945, together with C.H. Carlisle, she determined the exact structure of penicillin. The results contradicted general scientific thought at the time and therefore put researchers on the right path to developing further and more sophisticated uses for penicillin-based antibiotics, including the development of semisynthetic versions.
In the 50s, Dorothy and colleagues published an analysis of vitamin B12 which expanded the understanding of how this vital nutritional component functions and how it is utilised by the human body.
Perhaps what drove her most though was the study of insulin, the hormone used by the body to regulate blood sugar levels. The real challenge with insulin was that X-ray crystallography techniques were not advanced enough to map the full complexity of the molecule. This led to Dorothy spending years honing and improving the available methods to penetrate the mysteries of ever-more complicated structures. After 35 years of work – in 1969 – the internal structure of insulin was solved.