Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université Bourgogne Franche-Comté, 9 avenue Alain Savary, BP 47870, F-21078 Dijon Cedex, France.
Department of Chemistry, McGill University, Montréal, Québec H3A 0B8, Canada.
J Am Chem Soc. 2021 Oct 13;143(40):16332-16336. doi: 10.1021/jacs.1c07186. Epub 2021 Sep 28.
Colloidal bismuth therapeutics have been used for hundreds of years, yet remain mysterious. Here we report an X-ray pair distribution function (PDF) study of the solvolysis of bismuth disalicylate, a model for the metallodrug bismuth subsalicylate (Pepto-Bismol). This reveals catalysis by traces of water, followed by multistep cluster growth. The ratio of the two major species, {BiO} and {BiO}, depends on exposure to air, time, and the solvent. The solution-phase cluster structures are of significantly higher symmetry in comparison to solid-state analogues, with reduced off-center Bi displacements. This explains why such "magic-size" clusters can be both stable enough to crystallize and sufficiently labile for further growth.
胶体铋疗法已经使用了数百年，但仍然神秘。在这里，我们报告了对二水杨酸铋的溶剂解的 X 射线对分布函数（PDF）研究，这是金属药物次水杨酸铋（Pepto-Bismol）的模型。这揭示了痕量水的催化作用，随后是多步簇生长。两种主要物质{BiO}和{BiO}的比例取决于暴露于空气、时间和溶剂。与固态类似物相比，溶液相簇结构具有更高的对称性，其中 Bi 位移减小。这解释了为什么这种“神奇大小”的簇既能稳定到足以结晶，又能足够不稳定以进一步生长。
