Institute of Physics, University of Silesia, 75 Pulku Piechoty 1, 41-500 Chorzow, Poland.
Silesian Center for Education and Interdisciplinary Research (SMCEBI), 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland.
J Phys Chem B. 2022 May 26;126(20):3789-3798. doi: 10.1021/acs.jpcb.2c01284. Epub 2022 May 17.
Crystallization is one of the major challenges in using glassy solids for technological applications. Considering pharmaceutical drugs, maintaining a stable amorphous form is highly desirable for improved solubility. Glasses prepared by the physical vapor deposition technique got attention because they possess very high stability, taking thousands of years for an ordinary glass to achieve. In this work, we have investigated the effect of reducing film thickness on the α-relaxation dynamics and crystallization tendency of vapor-deposited films of celecoxib (CXB), a pharmaceutical substance. We have scrutinized its crystallization behavior above and below the glass-transition temperature (). Even though vapor deposition of CXB cannot inhibit crystallization completely, we found a significant decrease in the crystallization rate with decreasing film thickness. Finally, we have observed striking differences in relaxation dynamics of vapor-deposited thin films above the compared to spin-coated counterparts of the same thickness.
结晶是将玻璃态固体应用于技术领域的主要挑战之一。就药物而言，保持稳定的无定形形式对于提高溶解度非常理想。通过物理气相沉积技术制备的玻璃因其具有非常高的稳定性而受到关注，普通玻璃需要数千年才能达到这种稳定性。在这项工作中，我们研究了降低薄膜厚度对塞来昔布（CXB）的蒸气沉积膜的α弛豫动力学和结晶趋势的影响，CXB 是一种药物物质。我们在玻璃化转变温度（）以上和以下仔细研究了其结晶行为。尽管 CXB 的气相沉积不能完全抑制结晶，但我们发现随着薄膜厚度的降低，结晶速率显著降低。最后，我们观察到在高于 时，气相沉积的薄膜的弛豫动力学与相同厚度的旋涂薄膜有明显的差异。
