The structural investigation of amorphous pharmaceuticals is of paramount importance in comprehending their physicochemical stability. However, it has remained a relatively underexplored realm primarily due to the limited availability of high-resolution analytical tools. Here in this study, we utilized the combined power of X-ray pair distribution functions (PDFs) and solid-state nuclear magnetic resonance (ssNMR) techniques to probe the molecular packing of amorphous posaconazole and its amorphous solid dispersion at the molecular level. Leveraging synchrotron X-ray PDF data and employing the empirical potential structure refinement (EPSR) methodology, we unraveled the existence of a rigid conformation and discerned short-range intermolecular C–F contacts within amorphous posaconazole. Encouragingly, our ssNMR 19F–13C distance measurements offered corroborative evidence supporting these findings. Furthermore, employing principal component analysis on the X-ray PDF and ssNMR data sets enabled us to gain invaluable insights into the chemical nature of the intermolecular interactions governing the drug–polymer interplay. These outcomes not only furnish crucial structural insights facilitating the comprehension of the underlying mechanisms governing the physicochemical stability but also underscore the efficacy of synergistically harnessing X-ray PDF and ssNMR techniques, complemented by robust modeling strategies, to achieve a high-resolution exploration of amorphous structures.
Chen, Zhenxuan, et al. "Probing Molecular Packing of Amorphous Pharmaceutical Solids Using X-ray Atomic Pair Distribution Function and Solid-State NMR." Molecular Pharmaceutics, vol. 20, no. 11, Oct. 2023. https://doi.org/10.1021/acs.molpharmaceut.3c00628
Chen, Zhenxuan, Nie, Haichen, Benmore, Chris J., Smith, Pamela A., Du, Yong, Byrn, Stephen, Templeton, Allen C., & Su, Yongchao (2023). Probing Molecular Packing of Amorphous Pharmaceutical Solids Using X-ray Atomic Pair Distribution Function and Solid-State NMR. Molecular Pharmaceutics, 20(11). https://doi.org/10.1021/acs.molpharmaceut.3c00628
Chen, Zhenxuan, Nie, Haichen, Benmore, Chris J., et al., "Probing Molecular Packing of Amorphous Pharmaceutical Solids Using X-ray Atomic Pair Distribution Function and Solid-State NMR," Molecular Pharmaceutics 20, no. 11 (2023), https://doi.org/10.1021/acs.molpharmaceut.3c00628
@article{osti_2368566,
author = {Chen, Zhenxuan and Nie, Haichen and Benmore, Chris J. and Smith, Pamela A. and Du, Yong and Byrn, Stephen and Templeton, Allen C. and Su, Yongchao},
title = {Probing Molecular Packing of Amorphous Pharmaceutical Solids Using X-ray Atomic Pair Distribution Function and Solid-State NMR},
annote = {The structural investigation of amorphous pharmaceuticals is of paramount importance in comprehending their physicochemical stability. However, it has remained a relatively underexplored realm primarily due to the limited availability of high-resolution analytical tools. Here in this study, we utilized the combined power of X-ray pair distribution functions (PDFs) and solid-state nuclear magnetic resonance (ssNMR) techniques to probe the molecular packing of amorphous posaconazole and its amorphous solid dispersion at the molecular level. Leveraging synchrotron X-ray PDF data and employing the empirical potential structure refinement (EPSR) methodology, we unraveled the existence of a rigid conformation and discerned short-range intermolecular C–F contacts within amorphous posaconazole. Encouragingly, our ssNMR 19F–13C distance measurements offered corroborative evidence supporting these findings. Furthermore, employing principal component analysis on the X-ray PDF and ssNMR data sets enabled us to gain invaluable insights into the chemical nature of the intermolecular interactions governing the drug–polymer interplay. These outcomes not only furnish crucial structural insights facilitating the comprehension of the underlying mechanisms governing the physicochemical stability but also underscore the efficacy of synergistically harnessing X-ray PDF and ssNMR techniques, complemented by robust modeling strategies, to achieve a high-resolution exploration of amorphous structures.},
doi = {10.1021/acs.molpharmaceut.3c00628},
url = {https://www.osti.gov/biblio/2368566},
journal = {Molecular Pharmaceutics},
issn = {ISSN 1543-8384},
number = {11},
volume = {20},
place = {United States},
publisher = {American Chemical Society (ACS)},
year = {2023},
month = {10}}
Skinner, Lawrie B.; Benmore, Chris J.; Parise, John B.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 662, Issue 1https://doi.org/10.1016/j.nima.2011.09.031