Icker, M., P. Fricke, and S. Berger, Transfer of the Haupt-hyperpolarization to neighbor spins. J. Magn. Reson., 2012. 223(0): p. 148-150.
http://dx.doi.org/10.1016/j.jmr.2012.07.019
The NMR hyperpolarization observed for freely rotating methyl groups by exerting a temperature jump from 4.2 K to 298 K can be transferred to spins which have a spin, spin coupling with the carbon of the methyl group. First, a spin echo sequence readjusts the primary up/down signals to an in-phase multiplet. This in-phase magnetization is then decoupled and transferred by a simple COSY step using one scan. The polarization factors at the neighbor spins are about 50 by comparing their signal-to-noise ratio with the signal strength after full relaxation.