Born: 3 August 1959, Toyama City, Japan
Affiliation at the time of the award: Shimadzu Corp., Kyoto, Japan
Prize motivation: "for their development of soft desorption ionisation methods for mass spectrometric analyses of biological macromolecules."
Prize share: 1/4
When electrically charged molecules - ions - are accelerated by an electrical field, their speed depends on the ion's charge and weight. By measuring the time it takes for the ions to pass a certain distance, the incidence of different molecules in a test can be determined. It was impossible, however, to use this technique on large molecules, such as proteins, before large ions could be produced in gaseous form. In 1987 Koichiro Tanaka showed that laser pulses could blast apart protein molecules so that ions in gaseous form are produced.