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Transport Properties of Ibuprofen Encapsulated in Cyclodextrin Nanosponge Hydrogels: A Proton HR-MAS NMR Spectroscopy Study
Published on: August 15, 2016
2D solid-state NMR analysis of inclusion in drug-cyclodextrin complexes
Frederick G Vogt1, Mark Strohmeier
1Product Development, GlaxoSmithKline plc, 709 Swedeland Road, King of Prussia, Pennsylvania 19406, United States. Fred.G.Vogt@gsk.com
Molecular Pharmaceutics
|September 27, 2012
Summary
Solid-state NMR (SSNMR) effectively characterizes drug-cyclodextrin (CD) inclusion complexes. This technique confirms drug inclusion within the CD cavity and quantifies drug fractions in solid formulations.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Analytical Chemistry
Background:
- Cyclodextrin (CD) inclusion complexes enhance drug solubility and stability.
- Solid-state drug-CD complexes offer advantages in dosage form design and stability.
- Characterizing drug-CD interactions in solids is crucial for formulation development.
Purpose of the Study:
- To demonstrate the utility of 2D solid-state NMR (SSNMR) for characterizing drug-cyclodextrin (CD) inclusion complexes.
- To showcase the application of SSNMR in confirming drug inclusion within the CD cavity.
- To present quantitative SSNMR methods for analyzing drug-CD complexes.
Main Methods:
- Utilized 2D heteronuclear and homonuclear correlation SSNMR experiments.
- Employed (1)H, (13)C, (19)F, and (31)P nuclei for spectral analysis.
- Applied SSNMR to various drug-CD complexes, including diflunisal, adefovir dipivoxil, voriconazole, dexamethasone, and prednisolone with different CDs.
Main Results:
- Demonstrated successful inclusion of drugs within the CD cavity using SSNMR.
- Provided examples of SSNMR analysis for diverse drug-CD systems.
- Showcased quantitative analysis of included and free drug fractions in solid complexes.
Conclusions:
- 2D SSNMR is a powerful tool for probing drug-CD interactions in solid complexes.
- The presented SSNMR approach is broadly applicable for characterizing various drug-CD materials.
- SSNMR facilitates the development and quality control of solid drug-CD formulations.
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