Nobel laureate’s research led to MRIS

‘Toolmaker’ focused on atomic nuclei

Richard Ernst, a chemist who won a Nobel Prize for devising precise techniques to analyze the chemical properties of atoms, helping create the foundation of magnetic resonance imaging, which has had far-reaching applications in science and medicine, died June 4 in Winterthur, Switzerland. He was 87.

His death was announced by the Swiss Federal Institute of Technology in Zurich, where he had been a student and professor. The cause was not disclosed.

Ernst worked primarily in the field of nuclear magnetic resonance spectroscopy (NMR), combining elements of chemistry, physics and engineering. He concentrated on building and refining electronic equipment that bombarded atomic nuclei with radio frequencies. He then devised mathematical methods to measure the atomic responses and determine their chemical properties.

The field of NMR spectroscopy had been advanced in the 1940s by two scientists, Swiss-born Felix Bloch (then working at Stanford University) and Edward Mills Purcell, an American researcher at Harvard. They showed that radio waves could create a magnetic field that could alter the alignment of an atom’s nucleus. When the radio frequency is turned off, the nucleus tends to revert to its original alignment, giving off an electromagnetic signal that can be measured. Bloch and Purcell were jointly awarded the Nobel Prize in physics in 1952.

During the 1970s, after he had returned to Zurich as a professor, Ernst developed high-resolution, two-dimensional techniques that would allow larger molecules to be examined. Eventually, three-dimensional analysis of proteins and other molecules became possible, leading the way to magnetic resonance imaging, which has become widely used in diagnosing medical conditions.

There are many other applications, including analyzing the structure of chemical compounds and studying how drugs interact with various biological processes.

“It was my goal to develop something which could be used afterwards,” Ernst said in a 2001 interview published on the Nobel website.

“I was more interested in really designing tools. So I’m a toolmaker and not really a scientist in this sense and I wanted to provide other people these capabilities of solving problems.”