Home
Resources
Publications
Moving Towards Fast Characterization of Polymorphic Drugs by Solid-State NMR Spectroscopy

Moving Towards Fast Characterization of Polymorphic Drugs by Solid-State NMR Spectroscopy

Rosalynn Quiñones, Robbie J Iuliucci, Grayce Behnke, Ryanne Brown, Deben Shoup, Taylor M Riedel, Christine Plavchak, Brooke E Lininger, Jonathan M Spehar

J Pharm Biomed Anal. 2018 Jan 30;148:163-169.

PMID: 29035811

Abstract:

Solid-state nuclear magnetic resonance (SS-NMR) spectroscopy has become a common technique to study polymorphism in pharmaceutical solids at high-resolution. However, high-throughput application of high resolution SS-NMR spectroscopy is severely limited by the long 1H spin-lattice relaxation (T1) that is common to solid phase compounds. Here, we demonstrate the use of paramagnetic relaxation reagents such as chromium (III) acetylacetonate (Cr(acac)3) and nickel (II) acetylacetonate (Ni(acac)2) for fast data acquisition by significantly reducing the T1 value for carbamazepine Forms I, II, III, and dihydrate, cimetidine Forms A and B, nabumetone Form I, and acetaminophen Form I polymorphs. High resolution 13C cross-polarization and magic angle spinning were used to measure T1 values for each polymorph. In order to confirm the absence of polymorphic transitions during SS-NMR experiments, powder x-ray diffraction was implemented. The amount of chromium ions incorporated by the recrystallization process was quantified by using inductively coupled plasma optical emission spectroscopy. Our results suggest that the paramagnetic ions added to the polymorphs do not affect the polymorphic transformation or the quality of NMR spectra. We believe that this successful demonstration of fast data collection will enable high-throughput utilization of SS-NMR techniques to study polymorphic solids and could set the groundwork for NMR crystallography studies.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP21679312	Chromium(III) acetylacetonate		21679-31-2	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: