Attia Ali Kamal, Mohamed Abdel-Moety Mona
National Organization for Drug Control and Research, P.O. Box 29, Cairo, Egypt.
Adv Pharm Bull. 2013;3(1):147-52. doi: 10.5681/apb.2013.025. Epub 2013 Feb 7.
Thermal analysis (TGA, DTG and DTA) and differential scanning calorimetry (DSC) have been used to study the thermal behavior of terazosin hydrochloride (TER).
Thermogravimetric analysis (TGA/DTG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC) were used to determine the thermal behavior and purity of the used drug. Thermodynamic parameters such as activation energy (E*), enthalpy (∆H*), entropy (∆S*) and Gibbs free energy change of the decomposition (∆G*) were calculated using different kinetic models.
The purity of the used drug was determined by differential scanning calorimetry (99.97%) and specialized official method (99.85%) indicating to satisfactory values of the degree of purity. Thermal analysis technique gave satisfactory results to obtain quality control parameters such as melting point (273 ºC), water content (7.49%) and ash content (zero) in comparison to what were obtained using official method: (272 ºC), (8.0%) and (0.02%) for melting point, water content and ash content, respectively.
Thermal analysis justifies its application in quality control of pharmaceutical compounds due to its simplicity, sensitivity and low operational costs. DSC data indicated that the degree of purity of terazosin hydrochloride is similar to that found by official method.
采用热分析（TGA、DTG和DTA）及差示扫描量热法（DSC）研究盐酸特拉唑嗪（TER）的热行为。
采用热重分析（TGA/DTG）、差示热分析（DTA）和差示扫描量热法（DSC）测定所用药物的热行为和纯度。使用不同的动力学模型计算分解的活化能（E*）、焓（∆H*）、熵（∆S*）和吉布斯自由能变化（∆G*）等热力学参数。
通过差示扫描量热法测定所用药物的纯度为99.97%，采用专门的官方方法测定为99.85%，表明纯度程度令人满意。与官方方法得到的结果相比，热分析技术在获得熔点（273℃）、水分含量（7.49%）和灰分含量（零）等质量控制参数方面给出了令人满意的结果，官方方法得到的熔点、水分含量和灰分含量分别为（272℃）、（8.0%）和（0.02%）。
热分析因其简单、灵敏且运行成本低，证明了其在药物化合物质量控制中的应用价值。DSC数据表明盐酸特拉唑嗪的纯度与官方方法测定的结果相似。
