Properties of ibuprofen crystallized under various conditions: a comparative study.

Different crystal forms of the analgesic drug ibuprofen were prepared and characterized in this study. Various conditions were used for the crystallization: crystallization was carried out using the solvent change method, the temperature change method, and the solvent evaporation method. Crystals were grown from different solvents. Different crystal forms with different properties were observed: cubic, needle-shaped, and plate-shaped crystals were obtained. Spherical agglomeration occurs when crystallization is carried out in acetonitrile or methanol. Flowability of these spherical crystals is increased. All crystals were determined as isomorphic by differential scanning calorimetry and x-ray analysis--which queries doubtful results of recent publications. Properties like dissolution behavior and properties influencing the manufacturing of dosage forms--like flowability--differ. Thus the choice of the optimal preparation method influencing the crystal habit is important in manufacturing the drug ibuprofen.