%0 Journal Article %J Proceedings of the National Academy of Sciences of the United States of America %D 2003 %T Amplification of xenon NMR and MRI by remote detection %A Moule, A. J. %A Spence, M. M. %A Han, S. I. %A Seeley, J. A. %A Pierce, K. L. %A Saxena, S. %A Pines, A. %K field %X

A technique is proposed in which an NMR spectrum or MRI is encoded and stored as spin polarization and is then moved to a different physical location to be detected. Remote detection allows the separate optimization of the encoding and detection steps, permitting the independent choice of experimental conditions and excitation and detection methodologies. In the initial experimental demonstration of this technique, we show that taking dilute Xe-129 from a porous sample placed inside a large encoding coil and concentrating it into a smaller detection coil can amplify NMR signal. In general, the study of NMR active molecules at low concentration that have low physical filling factor is facilitated by remote detection. In the second experimental demonstration, MRI information encoded in a very low-field magnet (4-7 mT) is transferred to a high-field magnet (4.2 T) to be detected under optimized conditions. Furthermore, remote detection allows the utilization of ultrasensitive optical or superconducting quantum interference device detection techniques, which broadens the horizon of NMR experimentation.

%B Proceedings of the National Academy of Sciences of the United States of America %V 100 %P 9122-9127 %8 Aug 5 %@ 0027-8424 %G English %U ://WOS:000184620000007 %N 16 %M WOS:000184620000007 %! Amplification of xenon NMR and MRI by remote detection %R Doi 10.1073/Pnas.1133497100 %0 Journal Article %J Science %D 2001 %T Approach to high-resolution ex situ NMR spectroscopy %A Meriles, C. A. %A Sakellariou, D. %A Heise, H. %A Moule, A. J. %A Pines, A. %K echoes %X

Nuclear magnetic resonance (NMR) experiments are typically performed with samples immersed in a magnet shimmed to high homogeneity. However, there are many circumstances in which it is impractical or undesirable to insert objects or subjects into the bore of a high-field magnet. Here we present a methodology based on an adaptation of nutation echoes that provides resolved spectra in the presence of matched inhomogeneous static and radiofrequency fields, thereby opening the way to high-resolution exsitu NMR, The observation of chemical shifts is regained through the use of multiple-pulse sequences of correlated, composite z-rotation pulses, producing resolved NMR spectra of liquid samples.

%B Science %V 293 %P 82-85 %8 Jul 6 %@ 0036-8075 %G English %U ://WOS:000169780300032 %N 5527 %M WOS:000169780300032 %! Approach to high-resolution ex situ NMR spectroscopy %R Doi 10.1126/Science.1061498