期刊
JOURNAL OF PHARMACEUTICAL SCIENCES
卷 109, 期 11, 页码 3370-3377出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.xphs.2020.07.022
关键词
Solubility; Polymorphism; Crystallization; Thermodynamics; Activity coefficient; Ideality; Heat capacity
资金
- Swedish Research Council, Sweden [2019-5059]
- Synthesis and Solid State Pharmaceutical Centre - Science Foundation Ireland, Ireland under the European Regional Development Fund, European Union [12/RC/2275]
The thermodynamic relationship between FI and FII of ethyl 4-aminobenzoate (benzocaine) has been investigated. Slurry conversion experiments show that the transition temperature below which FI is stable is located between 302 K-303 K (29 degrees C-30 degrees C). The polymorphs FI and FII have been characterised by infrared spectroscopy (IR), Raman spectroscopy, transmission powder X-ray diffraction (XRPD) and differential scanning calorimetry (DSC). The isobaric solid state heat capacities have been measured by DSC. The quantitative thermodynamic stability relationship has been determined in a comprehensive thermodynamic analysis of the calorimetric data. The solubility of both polymorphs has been determined in eight pure organic solvents over the temperature range 278 K-323 K by a gravimetric method. The mole fraction solubility of benzocaine decreases in the order: 1,4-dioxane, acetone, ethyl acetate, chloroform, acetonitrile, methanol, n-butanol and toluene. Comparison with the determined activity of solid benzocaine forms shows that negative deviation from Raoult's law ideality is found in dioxane, acetone and ethyl acetate solutions, and positive deviation in solutions of the other investigated solvents. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of the American Pharmacists Association (R).
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据