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Updated: Jun 13, 2026

Spin Saturation Transfer Difference NMR (SSTD NMR): A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
Published on: November 12, 2016
Optimal transfer of spin-order between a singlet nuclear pair and a heteronucleus
Stephen Kadlecek1, Kiarash Emami, Masaru Ishii
1Department of Radiology, University of Pennsylvania, B-1 Stellar-Chance Labs, 422 Curie Blvd., Philadelphia, PA 19104, USA. stephen.kadlecek@uphs.upenn.edu
Abstract:
Intramolecular spin-order transfer is a useful technique for signal enhancement of insensitive and low-concentration molecular species. We present a closed-form, optimized pulse sequence which maximizes the efficiency of transfer between a singlet (para) nuclear pair and a vicinal heteronucleus. Neglecting the decay of coherences while the nuclei are in the transverse plane, the scheme is unity efficient for all combinations of internuclear scalar couplings. Efficiency loss due to T2-like decay is also minimized by keeping the sequence as short as possible. We expect this result to be useful for hyperpolarization experiments in which the spin-order originates in parahydrogen, as well as studies of singlet state decay aimed at longer-term storage of spin-order in hyperpolarized Magnetic Resonance Imaging.
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