Instituto de Estructura de la Materia-CSIC c/Serrano 119, 28006 Madrid (Spain).
Chemphyschem. 2013 Oct 7;14(14):3294-302. doi: 10.1002/cphc.201300321. Epub 2013 Aug 15.
The structure and stability of adenine crystals and thin layers has been studied by using scanning tunneling microscopy, X-ray diffraction, and density functional theory calculations. We have found that adenine crystals can be grown in two phases that are energetically quasi-degenerate, the structure of which can be described as a pile-up of 2D adenine planes. In each plane, the structure can be described as an aggregation of adenine dimers. Under certain conditions, kinetic effects can favor the growth of the less stable phase. These results have been used to understand the growth of adenine thin films on gold under ultra-high vacuum conditions. We have found that the grown phase corresponds to the α-phase, which is composed of stacked prochiral planes. In this way, the adenine nanocrystals exhibit a surface that is enantiopure. These results could open new insight into the applications of adenine in biological, medical, and enantioselective or pharmaceutical fields.
通过使用扫描隧道显微镜、X 射线衍射和密度泛函理论计算，研究了腺嘌呤晶体和薄膜的结构和稳定性。我们发现，腺嘌呤晶体可以在两个能量准简并的相中生长，其结构可以描述为二维腺嘌呤平面的堆积。在每个平面中，结构可以描述为腺嘌呤二聚体的聚集。在某些条件下，动力学效应可能有利于生长更不稳定的相。这些结果已被用于理解在超高真空条件下腺嘌呤在金上的薄膜生长。我们发现，所生长的相对应于 α 相，它由堆叠的前手性平面组成。通过这种方式，腺嘌呤纳米晶体表现出具有对映纯的表面。这些结果可能为腺嘌呤在生物、医学、对映选择性或药物领域的应用提供新的见解。
