Jacques Dubochet (born 8 June 1942 in Aigle) is a retired Swiss biophysicist best known for pioneering sample-preparation methods that made modern cryo-electron microscopy (cryo-EM) practical for high-resolution studies of biological macromolecules. His work focused on preserving hydrated specimens in a near-native state so that electron microscopes could image structures with minimal distortion.

Career and positions

Dubochet carried out significant research while associated with the European Molecular Biology Laboratory in Heidelberg (EMBL) and remained active in Swiss academic life as an honorary professor at the University of Lausanne. He has been linked to collaborative research networks in Germany and Switzerland and is widely regarded for combining practical laboratory technique with clear explanation of methodological principles.

Scientific contribution

The central technical advance credited to Dubochet is the reliable vitrification of water for electron microscopy: rapidly freezing aqueous samples so water forms amorphous, glass-like ice rather than damaging crystalline ice. Practically, this involved methods to plunge thin specimens into a cryogen fast enough to avoid ice crystal formation, producing thin films of vitreous ice that trap macromolecules in a solution-like environment. This approach reduced preparation artifacts and preserved structural details that were previously lost during drying or chemical fixation.

Methods and influence

Vitrification alone did not create high-resolution structures; it became powerful when combined with improvements in electron detectors, microscope optics and image processing algorithms. Together these advances transformed cryo-EM from a qualitative imaging tool into a quantitative method for determining three-dimensional molecular structures. Cryo-EM has since been applied to ribosomes, membrane proteins, virus particles and large protein complexes, and it now plays an important role in basic research and in areas such as drug discovery and vaccine design.

Recognition

In 2017 Dubochet shared the Nobel Prize in Chemistry with Joachim Frank and Richard Henderson for methods that established cryo-electron microscopy as a powerful tool for high-resolution structure determination of biomolecules in solution (Nobel Prize citation). The prize underscored how methodological advances in sample preparation can extend the capabilities of experimental instruments and open new research directions.

Legacy and public role

Beyond his laboratory work, Dubochet is recognized for making a delicate laboratory practice robust and reproducible. His publications and lectures emphasized reproducibility and accessibility of techniques, helping to spread cryo-EM methods to many laboratories worldwide. In retirement he has remained a public figure in science, speaking about research practice and the societal role of science.