液状および固体状核形成を伴うL-フェニルアラニンの光捕捉結晶化

抄録

  This paper presents an overview of the formation, growth, and dissolution behavior of a plate-like L-phenylalanine (L-Phe) crystal induced by laser trapping in its unsaturated solutions. By focusing the near-infrared laser onto the air/solution interface of the sample solution, a single crystal of L-Phe is formed at the focal spot. The generated crystal exhibits continuous two-dimensional growth while being trapped at the laser focus. The apparent crystal growth is paused by decreasing the laser power. This equilibrium state is kept for a certain period, and then the crystal begins to dissolve. Through the analysis of the temporal changes in the crystal surface area, it is suggested that the crystal is surrounded by a highly concentrated domain consisting of liquid-like clusters (pre-nucleation clusters). Thus, laser trapping-induced crystallization of L-Phe proceeds in two steps, where initially liquid nucleation leads to the domain formation and the following solid nucleation generates an L-Phe crystal.