hyperpolarised
Hyperpolarised refers to a non-equilibrium polarisation of nuclear spins in a sample, achieving populations of spin states far greater than those expected from thermal equilibrium at a given temperature and magnetic field. This enhanced spin polarisation translates into dramatically increased nuclear magnetic resonance (NMR) signals, enabling more sensitive measurements and imaging. The hyperpolarised state is typically transient, relaxing back toward equilibrium at a rate determined by the spin-lattice relaxation time (T1).
Hyperpolarisation is produced by several methods. Dynamic nuclear polarisation transfers polarisation from electron spins to nuclei
Applications include enhanced MRI and magnetic resonance spectroscopy, particularly in metabolic imaging with hyperpolarised 13C compounds
Limitations include short lifetimes of the hyperpolarised state, logistical and cost considerations, and the need for