(651g) Characterization and Formation Mechanism of Crystal Defects of Drug a

In the pharmaceutical industry, the internal defects of organic crystals seriously affects the quality and purity of the drug products. However, the mechanism of forming crystal defects has not been systematically reported so far. In this work, drug A, applied for curing cerebrovascular diseases, was selected as model compound. Firstly, it is found that there are three types of defects in drug A such as pores, cracks and inclusions. Then the effects of crystallization conditions such as solvent, temperature, supersaturation and stirring rate on the forming crystal defects were investigated. The Miller index of each crystal plane was determined by combining the results of X-ray diffraction and computer simulation. The interaction energy between each crystal face and the solvent molecules was calculated. The on-line SEM and AFM analysis of the crystal surface determined the local growth inhibition and the crystal growth mechanism of the specific crystal surface was investigated by the molecular arrangement characteristics, which is one of the important reasons for the formation of the crystal defects.