High Resolution Hyperpolarized J-Spectra with Parahydrogen Discrimination

I. PRINA; L. BULJUBASICH; R. H. ACOSTA

Journal of physical chemistry letters

American chemical society

Año: 2013 vol. 4 p. 3924 - 3928

1948-7185

Hyperpolarization by parahydrogen (PHIP) has become a powerful tool not only to overcome the low intrinsic sensitivity of Nuclear Magnetic Resonance (NMR) but also as a probe for catalytic reactions, contrast agent in magnetic resonance imaging (MRI) or in analytic chemistry. In complex systems the antiphase signals steaming from parahydrogen in a PASADENA (Parahydrogen and Synthesis Allow Dramatically enhanced Nuclear Alignment) experiment can be partially cancelled by the presence of large thermally polarized signals. In the present work we present a simple method to separate the thermal and hyperpolrized contributions by taking advantage of their very different evolution during a modified CPMG sequence. The separation is obtained in combination with a property of the Fast Fourier transform algorithm (FFT). The technique is experimentally demonstrated for a mixture of hyperpolarized 1-Hexene and a large amount of CH2Cl2.