Katona Gábor, Orsolya Jójártné Laczkovich, Szabóné Révész Piroska
Acta Pharm Hung. 2014;84(1):7-14.
An amorphous form of trehalose is easy to prepare by using a solvent method. The recrystallization kinetics can be followed well, which is important because of the occurrence of polymorphic forms of trehalose. This is especially significant in the case of dry powder inhalers. Spray-drying was used as a preparation method this being one of the most efficient technologies with which to obtain an amorphous form. This method can result in the required particle size and a monodisperse distribution with excellent flowability and with moreover considerable amorphization. In our work, trehalose was applied as a technological auxiliary agent, and literature data relating to the spray-drying technology of trehalose were collected. Studies were made of the influence of the spraying process on the amorphization of trehalose and on the recrystallization of amorphous trehalose during storage. Amorphous samples were investigated under 3 different conditions during 3 months. The recrystallization process was followed by differential scanning calorimetry and X-ray powder diffraction. The results demonstrated the perfect amorphization of trehalose during the spray-drying process. The glass transition temperature was well measurable in the samples and proved to be the same as the literature data. Recrystallization under normal conditions was very slow but at high relative humidity the process was accelerated greatly. Amorphous trehalose gave rise to dihydrate forms (gamma- and h-trehaloses) during recrystallization, and beta-trehalose was also identified as an anhydrous form.
采用溶剂法很容易制备出无定形海藻糖。可以很好地跟踪其重结晶动力学，这一点很重要，因为海藻糖存在多晶型。在干粉吸入器的情况下，这一点尤为重要。喷雾干燥被用作一种制备方法，这是获得无定形形式最有效的技术之一。这种方法可以得到所需的粒径和单分散分布，具有优异的流动性，而且还能实现相当程度的非晶化。在我们的工作中，海藻糖被用作一种技术辅助剂，并收集了与海藻糖喷雾干燥技术相关的文献数据。研究了喷雾过程对海藻糖非晶化以及储存过程中无定形海藻糖重结晶的影响。在3个月内对无定形样品在3种不同条件下进行了研究。通过差示扫描量热法和X射线粉末衍射跟踪重结晶过程。结果表明，在喷雾干燥过程中海藻糖实现了完美的非晶化。样品中的玻璃化转变温度很容易测量，并且与文献数据一致。在正常条件下重结晶非常缓慢，但在高相对湿度下该过程大大加速。无定形海藻糖在重结晶过程中产生了二水合物形式（γ-和h-海藻糖），并且β-海藻糖也被鉴定为无水形式。
