Article
Chemistry, Analytical
Karlis Berzins, Sara J. Fraser-Miller, Thomas Rades, Keith C. Gordon
Summary: In this study, the application of low-frequency Raman (LFR) spectroscopy in detecting the transition temperature of beta-relaxation (T-beta) in amorphous drugs was further investigated. The results highlighted the sensitivity and practical usefulness of the LFR technique in elucidating subtle changes in molecular dynamics within amorphous pharmaceutical systems.
ANALYTICAL CHEMISTRY
(2022)
Article
Medicine, Research & Experimental
Jingwen Song, Kohsaku Kawakami
Summary: The aqueous solubility of APIs is crucial for drug absorption. Amorphization of API can enhance solubility, but crystal nuclei may develop into crystals, limiting dissolution advantage. In this study, it was found that amorphous CEL could form nuclei at freezing temperatures without crystal growth. Only room temperature annealed CEL could effectively achieve a supersaturated state during dissolution. Heterogeneous nucleation and competition between amorphous dissolution and crystallization were observed.
MOLECULAR PHARMACEUTICS
(2023)
Article
Chemistry, Multidisciplinary
Alexy P. Freitas, Raj Kumar Ramamoorthy, Maxime Durelle, Eric Larquet, Isabelle Maurin, Fabienne Testard, Corinne Chevallard, Thierry Gacoin, David Carriere
Summary: Research on nanocrystals synthesized in solution is driven by their unique physical properties determined by sizes and shapes. However, the limited understanding of crystallization, particularly the prevalence of noncrystalline intermediates, poses a challenge. In situ X-ray scattering reveals that the nucleation and growth of nanocrystals are constrained within amorphous intermediates, which play a crucial role in determining the final crystal characteristics and size.
Article
Pharmacology & Pharmacy
Jie Zhang, Ziqing Yang, Liquan Luo, Kang Li, Taotao Zi, Junjie Ren, Lei Pan, Ziyue Wang, Zihao Wang, Minzhuo Liu, Zhihong Zeng
Summary: This study investigated the effects of poloxamer on the crystallization of amorphous clotrimazole (CMZ). The addition of poloxamer significantly decreased the glass transition temperature (Tg) of CMZ and accelerated the growth of Form 1 and Form 2 crystals. Moreover, the added poloxamer exhibited different effects on nucleation of the CMZ polymorphs, with a significant increase in Form 1 nucleation rate but a decrease or no change in Form 2 nucleation rate.
Review
Materials Science, Ceramics
Linya Qiang, Xiaozhen Zhang, Yizhaotong Ai, Yin Zhuang, Jing Sheng, Huayu Zhao, Jinxing Ni, Kai Yang
Summary: A novel Al2O3-GdAlO3 (GAP) amorphous ceramic coating was successfully deposited in-situ via atmospheric plasma spraying (APS). The crystallization behavior and thermal stability mechanism of the Al2O3-GAP coating were investigated, revealing its high activation energy and good crystallization characteristics, making it suitable for high-temperature applications.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Materials Science, Ceramics
Zhongbin Yin, Lanlin Yi, Fanhou Kong, Zelin Chen, Xiaohui Fang, Ruixiang Zhang, Yongjun Chen, Hong Jiang, Changjiu Li
Summary: The study investigated the effect of an electric field on the crystal grains number in MAS glass-ceramics. The results showed that an increase in electric-field voltage led to a gradual increase in crystal grains number in MAS glass-ceramics when the voltage reached 1200V. Additionally, the introduction of an electric field promoted the separation of titanium from the silicon-oxygen network framework and facilitated crystal growth.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2021)
Article
Pharmacology & Pharmacy
Naho Hanada, Kenjirou Higashi, Zhijing Zhao, Keisuke Ueda, Kunikazu Moribe
Summary: Ternary amorphous solid dispersions (ASDs) of probucol (PBC)/polymer/surfactant were successfully prepared by hot-melt extrusion method. The ASDs stabilized amorphous PBC mainly through hydrogen bonds formed between PBC and the polymer (PVP). Colloidal dispersions of amorphous PBC nanoparticles were obtained from the ASD using a weight ratio of 1:4:2 for PBC/PVP/P407, and the stability of the amorphous state was confirmed through storage experiments.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Pharmacology & Pharmacy
Katsutoshi Yamaguchi, Ryo Mizoguchi, Kohsaku Kawakami, Tamaki Miyazaki
Summary: Amorphization is an effective method to improve the solubility and bioavailability of poorly watersoluble compounds. However, it can lead to chemical and physical instability. This study found a correlation between the physical stability of amorphous compounds and molecular mobility, providing a more accurate prediction for long-term physical stability.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2022)
Article
Chemistry, Medicinal
Andrew Toye Ojo, Ping Lee
Summary: This paper establishes a mechanistic model for predicting the stability of amorphous solid dispersions (ASD) by incorporating fundamental physical parameters and API-dependent coefficients. The model considers both thermodynamic and kinetic drivers, describing temporal stability through a system of coupled differential equations. Experimental observations validate the model's utility in predicting the physical stability of ASDs.
JOURNAL OF PHARMACEUTICAL SCIENCES
(2021)
Article
Materials Science, Ceramics
Jae-ho Lee, Tae-min Yeo, Jung-Wook Cho
Summary: The effects of Li2O on the crystallization behavior of Cuspidine in CaO-SiO2-CaF2 glass were studied, revealing that Li2O could affect the crystallization rate and nucleation was identified as the limiting step of the crystallization process.
CERAMICS INTERNATIONAL
(2021)
Article
Multidisciplinary Sciences
Matthew E. McKenzie, Binghui Deng, D. C. Van Hoesen, Xinsheng Xia, David E. Baker, Aram Rezikyan, Randall E. Youngman, K. F. Kelton
Summary: Nucleation is a structural fluctuation that requires reaching a critical size to form a new phase. Cluster composition and pathways to the new phase are important details affecting the nucleation process. In barium silicate glasses, a silica rich core plays a dominant role in nucleation.
SCIENTIFIC REPORTS
(2021)
Article
Crystallography
Yanan Wang, Yong Wang, Jin Cheng, Haibiao Chen, Jia Xu, Ziying Liu, Qin Shi, Chen Zhang
Summary: This article provides a summary of the characteristics and technologies related to amorphous pharmaceutical solids, highlighting a deeper understanding of the crystallization mechanism. These advanced techniques can aid in the development of more effective amorphous drugs.
Article
Chemistry, Multidisciplinary
Susan A. Rigter, Xueying L. Quinn, Rishi E. Kumar, David P. Fenning, Philippe Massonnet, Shane R. Ellis, Ron M. A. Heeren, Katrine L. Svane, Aron Walsh, Erik C. Garnett
Summary: The addition of acetate precursors promotes rapid desolvation for making a variety of compositions of amorphous lead halide perovskite films. By controlling the amount of acetate, the transition from fully crystalline to fully amorphous films can be tuned, resulting in an intermediate state with crystalline islands embedded in an amorphous matrix.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Jaroslav Bartak, Jiri Malek, Kushal Bagchi, M. D. Ediger, Yuhui Li, Lian Yu
Summary: The study monitored the temporal evolution of nanoholes in amorphous selenium with atomic force microscopy, and found that the surface diffusion coefficient can be used to predict surface crystallization rates in chemically diverse materials.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Yun Cao, Keke Zhang, Zhenguo Gao, Jingkang Wang, Sohrab Rohani, Junbo Gong
Summary: The development of metastable form crystals of active pharmaceutical ingredients can improve the bioavailability of poorly soluble drugs. The study found that the solvent properties and silica pore size affect the polymorphic outcomes. The confined metastable form exhibited enhanced physical stability and a faster dissolution rate compared to the bulk form.
CRYSTAL GROWTH & DESIGN
(2022)