Active control of growth mode and polymorph nucleation of organic molecules by femtosecond laser: For development of medical drugs

Abstract

Polymorphic control is a matter of great importance in the pharmaceutical industry. In the research and development of a new drug, all polymorphs of the target compound are investigated by the screening process, and the most suitable with the appropriate properties is selected for the commercial product. Thus, “selective crystallization” of a “high-quality” unstable phase is needed. In previous study, we have developed polymorph controlling techniques; crystallization of the metastable phase by ultrasonic irradiation or femtosecond laser irradiation, and polymer induced nucleation. In order to apply the techniques to crystallization polymorphs of various compounds, in this study we have sophisticated them using a challenging model materials, indomethacin, acetaminophen and aspirin (acetylsalicylic acid). Here we will introduce the crystallization technique of metastable phase and the control technique of crystal growth mode by femtosecond laser irradiation.