Who Won the Nobel Prize for Vitamin B12?

December 28, 2025 •

3 min read

In 1964, the Nobel Prize in Chemistry was awarded to a British chemist for her determination of the structure of important biochemical substances, including vitamin B12. This pivotal scientific achievement recognized the groundbreaking work that decoded the complex structure of one of the largest and most intricate vitamins known at the time.

Quick Summary

This article details the groundbreaking work of Dorothy Crowfoot Hodgkin, the 1964 Nobel Prize in Chemistry winner, who used X-ray crystallography to determine the structure of vitamin B12. It covers her methodology, the vitamin's complex chemistry, and its biological importance in preventing pernicious anemia and supporting neurological health.

Key Points

The Winner: Dorothy Crowfoot Hodgkin won the Nobel Prize in Chemistry in 1964 for determining the structure of vitamin B12.
Methodology: She used X-ray crystallography to map the three-dimensional atomic structure of the complex molecule.
Biological Significance: Understanding B12's structure was vital for treating pernicious anemia, a deficiency that impairs red blood cell production.
Structural Complexity: Vitamin B12, or cobalamin, is a coordination complex with a central cobalt atom, making its structural analysis an extraordinary challenge.
Total Synthesis: Robert Burns Woodward and Albert Eschenmoser later accomplished the total chemical synthesis of vitamin B12 in 1973, a separate achievement from Hodgkin's work.
Impact on Health: Her discovery enabled the effective production and administration of vitamin B12 for those with dietary deficiencies or absorption issues.

Dorothy Hodgkin: The Woman Who Solved B12

British chemist Dorothy Crowfoot Hodgkin (1910–1994) was awarded the 1964 Nobel Prize in Chemistry for her revolutionary work in determining the structures of critical biochemical substances. Her most celebrated achievements in this field included elucidating the structures of both penicillin and the remarkably complex vitamin B12. Utilizing the advanced technique of X-ray crystallography, Hodgkin spent eight arduous years working to map the atomic arrangement of vitamin B12, a molecule with 181 atoms, proving the method's potential for even the most complicated molecules.

The Method: X-ray Crystallography

To unravel the structure of vitamin B12, Hodgkin relied on X-ray crystallography, a technique pioneered in 1912 by Max von Laue. In this method, a beam of X-rays is aimed at a crystalline sample of the molecule. The atoms in the crystal cause the X-rays to diffract into a specific pattern, which can be captured on a photographic plate. By analyzing this intricate diffraction pattern, scientists can deduce the three-dimensional arrangement of the atoms in the crystal lattice. The process is highly complex and, in the pre-computer era, required immense patience and countless hours of calculations. Hodgkin's success with vitamin B12 validated the power of X-ray crystallography for larger and more complex molecules.

The Discovery: Unlocking the Structure of Cobalamin

Vitamin B12, also known as cobalamin, is a coordination complex containing a single central cobalt atom. This cobalt atom is nestled within a corrin ring, a macrocyclic structure similar to the porphyrin ring found in heme. Hodgkin's team first determined in 1956 that the vitamin contained a cobalt atom, a finding that was key to its structural analysis via X-ray crystallography. By leveraging this "heavy atom"—which scatters X-rays more strongly—her team was able to solve the structure. The work was published over two years, solidifying a major milestone in biochemistry.

Why Vitamin B12 is so Important

The determination of vitamin B12's structure had profound implications for medicine, particularly for the treatment of pernicious anemia. This autoimmune condition prevents the body from absorbing vitamin B12, leading to a deficiency that causes a decline in red blood cell production, neurological damage, and other serious health issues. Understanding the structure of B12 allowed for its efficient production and paved the way for effective treatment through supplements and injections.

The Importance of Synthesis

While Dorothy Hodgkin won the prize for determining the structure, the total chemical synthesis of vitamin B12 is another monumental achievement, involving a collaboration between two other scientific giants, Robert Burns Woodward and Albert Eschenmoser. The synthesis was completed in 1973 after nearly 12 years of work involving almost 100 researchers. The complexity of the molecule and the intricate process of building it from scratch cemented its legendary status in organic chemistry. It is essential to distinguish between the determination of the molecule's existing structure and its complete artificial creation in a lab.

Comparison of Key Vitamin B12 Milestones


Milestone	Researcher(s)	Year	Awarded Nobel Prize	Impact
Isolation	Mary Shaw Shorb, Karl Folkers et al.	1948	No	First to obtain pure, crystalline B12
Structure Determination	Dorothy Hodgkin	1956	Yes (1964)	Unveiled the complex 3D atomic structure
Total Chemical Synthesis	Robert Burns Woodward & Albert Eschenmoser	1973	Woodward (1965), Eschenmoser (No)	Pushed the boundaries of organic chemistry
Microbial Production	Various researchers	Ongoing	No	Enabled large-scale, cost-effective production

Conclusion

In conclusion, the person who won the Nobel Prize for determining the structure of vitamin B12 was Dorothy Crowfoot Hodgkin in 1964. Her work, using X-ray crystallography, was a landmark achievement that provided the first detailed look at this complex molecule. Her discovery fundamentally changed our understanding of B12 and contributed significantly to the medical treatment of pernicious anemia. It is a powerful reminder of how foundational scientific insights can lead to immense practical benefits for human health. While her work is sometimes confused with the later total synthesis by Woodward and Eschenmoser, Hodgkin's achievement stands as a distinct and monumental contribution to the field of chemistry. Learn more about the science behind Nobel Prizes.

Frequently Asked Questions

Dorothy Crowfoot Hodgkin was the first person to win a Nobel Prize specifically for work on vitamin B12. She was awarded the 1964 Nobel Prize in Chemistry for elucidating its chemical structure using X-ray techniques.

X-ray crystallography is a technique that uses X-rays to determine the three-dimensional arrangement of atoms within a crystal. Hodgkin used it to analyze the diffraction patterns created by a crystalline sample of vitamin B12, enabling her to deduce the molecule's complex structure.

While Hodgkin won for the structure, the later total chemical synthesis of vitamin B12 in 1973 was a collaborative effort led by Robert Burns Woodward and Albert Eschenmoser. Woodward had previously won the Nobel Prize in 1965, but not specifically for the B12 synthesis.

At the time, vitamin B12 was the largest and most complex biomolecule to have its structure determined. The sheer number of atoms (181) and the intricate arrangement required groundbreaking dedication and refinement of the X-ray crystallography method.

Understanding the structure of vitamin B12 was crucial for producing it synthetically and for developing effective treatments for conditions like pernicious anemia, an autoimmune disorder that impairs B12 absorption.

Structure determination is the process of discovering a molecule's existing shape, while synthesis is the process of creating that molecule artificially from simpler chemical precursors. Hodgkin solved the puzzle of its structure, while Woodward and Eschenmoser later built it from scratch.

Pernicious anemia is an autoimmune condition where the body cannot produce a protein called intrinsic factor, which is essential for absorbing vitamin B12. This deficiency leads to a shortage of red blood cells and can cause serious neurological damage.