標題: Pseudopolymorph Control of L-Phenylalanine Achieved by Laser Trapping
作者: Wu, Chi-Shiun
Hsieh, Pei-Yun
Yuyama, Ken-ichi
Masuhara, Hiroshi
Sugiyama, Teruki
交大名義發表
應用化學系
National Chiao Tung University
Department of Applied Chemistry
公開日期: 1-Sep-2018
摘要: We demonstrate pseudopolymorph control of L-phenylalanine (L-Phe) with laser trapping method by tuning laser power, polarization, and initial solution concentration. When a continuous-wave near-infrared laser beam of 1064 nm was focused at an air/solution interface of L-Phe D2O solutions with different saturation, L-Phe crystallization was always observed within 30 min-irradiation, even from unsaturated solution. Either whisker- or plate-like crystals were generated depending on given conditions, and identified by Raman spectroscopy to be two L-Phe pseudopolymorphs of monohydrate and anhydrous forms, respectively. The absolute control of L-Phe pseudopolymorphism was achieved by changing the initial solution concentration. In unsaturated solution, laser trapping always produced only one anhydrous crystal at the focus, which can never be produced on spontaneous nucleation at ordinary temperatures and pressures, while in supersaturated solution, a number of monohydrate crystals were densely distributed in an area ranging from 500 mu m to 1 mm away from the focus. Moreover, in saturated solution, laser power and polarization contributed to the pseudopolymorphism. As laser power was increased, linearly and circularly polarized laser irradiation increased the formation probability of the anhydrous and monohydrate crystals, respectively. The dynamics and mechanism of laser trapping-induced pseudopolymorphism of L-Phe are discussed in view of the formation of a highly concentrated domain consisting of the liquid-like clusters and the stability of the clusters in the domain under electromagnetic field of trapping laser.
URI: http://dx.doi.org/10.1021/acs.cgd.8b00796
http://hdl.handle.net/11536/148121
ISSN: 1528-7483
DOI: 10.1021/acs.cgd.8b00796
期刊: CRYSTAL GROWTH & DESIGN
Volume: 18
起始頁: 5417
結束頁: 5425
Appears in Collections:Articles