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Updated: Aug 20, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
The use of 13C labeling to enhance the sensitivity of 13C solid-state CPMAS NMR to study polymorphism in low dose
Kees-Jan Booy1, Peter Wiegerinck, Jan Vader
1Pre- and early Clinical Development, Organon, P.O. Box 20, 5340BH Oss, The Netherlands.
Abstract:
(13)C labeling was used to enhance the sensitivity of (13)C solid-state NMR to study the effect of tabletting on the polymorphism of a steroidal drug. The steroidal drug Org OD 14 was (13)C labeled and formulated into tablets containing only 0.5-2.5% active ingredient. The tablets were subsequently studied by solid-state (13)C CPMAS NMR. The crystalline form present in tablets could readily be analyzed in tablets. No change in crystalline form was observed as a result of formulation or in subsequent stability studies. Solid-state NMR in combination with (13)C labeling can, in suitable cases, be used as a strategy to study the effect of formulation on the polymorphism of low dose drugs.
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