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Fiona Coyer - One of the best experts on this subject based on the ideXlab platform.

Natasha Koroloff - One of the best experts on this subject based on the ideXlab platform.

Kunikazu Moribe - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Drug-Polymer Interactions through Hypromellose Acetate Succinate Substituents on the Physical Stability on Solid Dispersions Studied by Fourier-Transform Infrared and Solid-State Nuclear Magnetic Resonance.
    Molecular pharmaceutics, 2019
    Co-Authors: Yuya Ishizuka, Keisuke Ueda, Hitomi Okada, Junpei Takeda, Masatoshi Karashima, Koji Yazawa, Kenjirou Higashi, Kohsaku Kawakami, Yukihiro Ikeda, Kunikazu Moribe
    Abstract:

    The present study evaluated the specific intermolecular interactions between carbamazepine (CBZ) and substituents of Hypromellose acetate succinate (HPMC-AS), as well as the mechanism of inhibition of recrystallization of solid dispersions (SDs) using Fourier-transform infrared (FTIR) and solid-state nuclear magnetic resonance (NMR) spectroscopy. CBZ and HPMC derivatives, including HPMC, Hypromellose acetate (HPMC-A), and Hypromellose succinate (HPMC-S), were spray-dried to prepare CBZ/polymer spray-dried samples (SPDs). CBZ/HPMC SPD and CBZ/HPMC-A SPD recrystallized within 10 days at 60 °C and 0% relative humidity, whereas CBZ/HPMC-S SPD maintained its amorphous state for a longer period. FTIR and solid-state NMR measurements using 13C cross polarization (CP), 1H single-pulse, and 1H–15N CP-based heteronuclear single quantum correlation filter experiment with very fast magic angle spinning (MAS) at 70 kHz identified molecular interactions in CBZ/polymer SPDs. Although the HPMC backbone and substituents d...

  • Effect of Drug-Polymer Interactions through Hypromellose Acetate Succinate Substituents on the Physical Stability on Solid Dispersions Studied by Fourier-Transform Infrared and Solid-State Nuclear Magnetic Resonance.
    Molecular pharmaceutics, 2019
    Co-Authors: Yuya Ishizuka, Keisuke Ueda, Hitomi Okada, Junpei Takeda, Masatoshi Karashima, Koji Yazawa, Kenjirou Higashi, Kohsaku Kawakami, Yukihiro Ikeda, Kunikazu Moribe
    Abstract:

    The present study evaluated the specific intermolecular interactions between carbamazepine (CBZ) and substituents of Hypromellose acetate succinate (HPMC-AS), as well as the mechanism of inhibition...

  • Effect of Drug–Polymer Interactions through Hypromellose Acetate Succinate Substituents on the Physical Stability on Solid Dispersions Studied by Fourier-Transform Infrared and Solid-State Nuclear Magnetic Resonance
    2019
    Co-Authors: Yuya Ishizuka, Keisuke Ueda, Hitomi Okada, Junpei Takeda, Masatoshi Karashima, Koji Yazawa, Kenjirou Higashi, Kohsaku Kawakami, Yukihiro Ikeda, Kunikazu Moribe
    Abstract:

    The present study evaluated the specific intermolecular interactions between carbamazepine (CBZ) and substituents of Hypromellose acetate succinate (HPMC-AS), as well as the mechanism of inhibition of recrystallization of solid dispersions (SDs) using Fourier-transform infrared (FTIR) and solid-state nuclear magnetic resonance (NMR) spectroscopy. CBZ and HPMC derivatives, including HPMC, Hypromellose acetate (HPMC-A), and Hypromellose succinate (HPMC-S), were spray-dried to prepare CBZ/polymer spray-dried samples (SPDs). CBZ/HPMC SPD and CBZ/HPMC-A SPD recrystallized within 10 days at 60 °C and 0% relative humidity, whereas CBZ/HPMC-S SPD maintained its amorphous state for a longer period. FTIR and solid-state NMR measurements using 13C cross polarization (CP), 1H single-pulse, and 1H–15N CP-based heteronuclear single quantum correlation filter experiment with very fast magic angle spinning (MAS) at 70 kHz identified molecular interactions in CBZ/polymer SPDs. Although the HPMC backbone and substituents did not interact notably with CBZ and disrupt CBZ–CBZ intermolecular interactions (formed in the amorphous CBZ), acetate and succinate substituents on HPMC-A and HPMC-S disrupted CBZ–CBZ intermolecular interactions through formation of CBZ/polymer interactions. The acetate substituent formed a hydrogen bond with the NH2 group of CBZ, whereas the succinate substituent formed molecular interactions with both the CO and NH2 groups of CBZ. Formation of relatively strong molecular interactions between CBZ and the succinate substituent followed by disruption of CBZ–CBZ intermolecular interactions effectively stabilized the amorphous state of CBZ in CBZ/HPMC-S SPD. The correlation between CBZ–polymer interactions and ability of polymers to effectively inhibit CBZ recrystallization is reflected in various commercial HPMC-AS. For example, HPMC-AS LF grade, containing higher amounts of the succinate group, was found to effectively inhibit the recrystallization of CBZ through strong molecular interactions as compared with the HPMC-AS HF grade. The present study demonstrated that a detailed investigation of molecular interactions between the drug and the polymer using FTIR and solid-state NMR spectroscopy could contribute to a suitable selection of the SD carrier

Robert J. Boots - One of the best experts on this subject based on the ideXlab platform.

Jeffrey Lipman - One of the best experts on this subject based on the ideXlab platform.