2026/07/01 by Felix Lücke, Nils Sassenberg, Denis Gebauer · 1 voice
Chemistry · Materials Science · Pharmacology, Toxicology and Pharmaceutics · #Crystallization and Solubility Studies #Crystallography and molecular interactions #Drug Solubulity and Delivery Systems
paper · doi:10.1002/cmtd.70140
openalex publication_date 2026/07/01 · openalex created_date 2026/07/07 · openalex updated_date 2026/07/23
Organic crystallization plays a crucial role in industrial processes, including purification, separation, and synthesis. Insight into the nucleation pathway—particularly into precursors and intermediate phases preceding the final crystalline product—is essential for improved control over crystallization outcomes. Challenges such as undesired polymorph formation or limited solubility can be addressed more effectively when the underlying mechanisms are understood. In this work, we present a method enabling the systematic investigation and quantitative assessment of early‐stage organic crystallization at constant pH and temperature. Functionalized benzoic acid derivatives exhibit distinct molecular binding prior to phase separation, influenced by both functional group and pH. We detect less stable (more soluble) intermediate phases before transformation into the final crystalline products. Solubility limits and dissociation constants are determined in good agreement with literature values. The method provides a tool for elucidating mechanisms of organic crystallization and identifying metastable or amorphous intermediates, as well as quantitatively exploring additive effects. For example, minor amounts of ethanol stabilize dense liquid intermediates in the case of ibuprofen. These findings are relevant for fundamental nucleation research and for research and development, particularly in pharmaceutical contexts.