Amorphization of sugar hydrates upon milling

Prior research has shown that anhydrous sugars can be transformed into amorphous forms through mechanical milling. However, the behavior of hydrates under similar conditions remains unclear. Established knowledge suggests that milling can induce amorphization in certain materials. Yet, the role of water in this process is not fully understood. This uncertainty drives the need to investigate hydrates specifically. No prior work has directly compared hydrates and their anhydrous forms under identical milling conditions. The presence of water molecules may influence the amorphization process. Understanding this could improve pharmaceutical formulation techniques. The gap in knowledge about hydrate amorphization motivates this study.

This study aims to determine whether hydrates of lactose, trehalose, and glucose can be amorphized through mechanical milling. The researchers focus on comparing hydrates with their anhydrous counterparts. They use identical milling procedures for consistency. The goal is to identify the role of structural water in amorphization. Previous work suggests hydrates may resist amorphization. The authors test this hypothesis experimentally. They seek to clarify why hydrates behave differently than anhydrous forms. Their findings may inform solid-state processing strategies.

The study uses mechanical milling to process lactose monohydrate, trehalose dihydrate, and glucose monohydrate. The same milling conditions are applied to anhydrous forms of these sugars. Differential scanning calorimetry is used to assess thermal transitions. Powder X-ray diffraction confirms structural changes after milling. The authors compare the outcomes of hydrates and anhydrous forms. They measure the glass transition temperature as a key parameter. Structural water content is analyzed for its effect on amorphization. The experimental design ensures reproducibility and comparability.

Lactose monohydrate amorphizes under milling, but trehalose dihydrate and glucose monohydrate remain crystalline. The amorphization of lactose is attributed to its lower glass transition temperature. Structural water in hydrates may act as a plasticizer. This lowers the glass transition temperature below milling conditions. The other hydrates have higher glass transition temperatures. This prevents them from amorphizing during milling. The results confirm that hydrates resist amorphization more than anhydrous forms. The findings support the role of the glass transition in milling-induced amorphization.

The study shows that not all hydrates amorphize under identical milling conditions. Lactose monohydrate amorphizes, but trehalose and glucose hydrates do not. The difference is linked to the plasticizing effect of structural water. This effect lowers the glass transition temperature in lactose hydrate. The authors suggest that this explains the selective amorphization observed. Their findings align with prior knowledge about glass transition behavior. The results clarify why hydrates are harder to amorphize than anhydrous forms. These conclusions may guide future milling strategies for hydrates.