Nuclear magnetic resonance magnet actively cooled by pulse tube refrigerator

High field NMR spectrometers have been an essential tool for biomolecular scientists for many years. They have been instrumental in the pursuit of understanding of the structure, function and dynamics of proteins and other biological molecules. In addition, NMR is increasingly used for small molecule applications such as metabonomics, providing capabilities that aid drug discovery, as well as general organic and inorganic chemistry [M. Pellecchia , Nature Reviews Drug Discovery 1, 211 (2002)]. However, access to these systems is restricted due to the requirement to periodically refill them with liquid cryogens. This is both logistically demanding and expensive. A new system combining NMR spectrometry and Pulse Tube Refrigeration (PTR) has been developed and successfully tested. This approach eliminates the dependence on liquid cryogens, reduces spectrometer downtime, and also significantly reduces the size of the system. In the near future this new type of analytical tool may become ubiquitous in biomedical and chemical laboratories. © 2005 American Institute of Physics.