Since the first demonstration of nuclear induction in bulk matter in 1946, by Purcell and Bloch at Harvard and Stanford respectively, nuclear magnetic resonance (NMR) has become unarguably the most important and widely used physical tool for investigating matter. Its range is astonishing, encompassing such diverse areas as imaging of tissues in living animals, organic and inorganic materials in the liquid, liquid crystal or solid phase to quantum computing. The growth of NMR into this pre-eminent state has been a long and arduous journey, punctuated with the award of the Nobel Prize to four scientists for their contributions to NMR. Purcell and Bloch shared the 1952 Nobel Prize in physics and Richard Ernst was awarded the 1991 Nobel Prize in Chemistry for his contributions to the development of the methodology of high resolution NMR spectroscopy. Only a few weeks ago the Nobel prize for 2002 in Chemistry was awarded to three scientists, one of whom is Kurt Wtithrich for his development of NMR spectroscopy for determining the three-dimensional structure of biological macromolecules in solution, and the other two being John Fenn and Koichi Tanaka for their development of soft desorption ionization methods for mass spectrometric analyses of biological macromolecules. The growth of NMR as a bioanalytical tool has been aided by developments in other seemingly unrelated areas of science such as solid state physics and material science for the design and construction of exquisitely sensitive electronic components for the detection of very weak radio frequency signals and concurrently development of high field superconducting magnets that today range in field, strength from 7.05 to 21.14 T (10,000 Gauss=1 T, for comparison the earth's magnetic field is 0.5 Gauss) that increase the sensitivity of detection and resolution. Today NMR signals can be recorded on samples ranging in quantity from a few tenths of a milligram to a milligram (Purcell recorded his first NMR signal using a 1 kg block of paraffin wax as a sample). Last but not the least, bioanalytical NMR has benefited enormously from methodological improvements in genetic engineering and molecular biology for production of native proteins in quantities, usually milligrams, necessary for structural studies.
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