Muddassir Mohd
Department of Chemistry, College of Science, King Saud University Riyadh 11451 Saudi Arabia
RSC Adv. 2020 Nov 6;10(66):40543-40551. doi: 10.1039/d0ra07274e. eCollection 2020 Nov 2.
Metal complexes containing coordination bonds play a prominent role in many essential biological systems in living organisms. Examples of such complexes include hemoglobin containing iron, chlorophyll containing magnesium, and vitamin B containing cobalt. Although the thermodynamic and other collective properties of metal complexes are well established, their mechanical stability remains minimally explored. Single-molecule force spectroscopy has been used to determine the structural and mechanical properties of chemical bonds; however, it has been minimally utilized in the field of coordination chemistry. Thus, here, we select a unique molecule of interest, HA-Ru, {HA = hyaluronan and Ru = (bpy)Ru(4-pyNH)} and subject it to single-molecule force spectroscopy analysis to directly study its bond-rupture process. The molecule is excited by blue-light irradiation, and surprisingly, this whole process could be reversed without applying any external energy, such as heat or solvent exposure. Our results demonstrate the reversibility of the luminescent Ru complex to its original state, a phenomenon that can be further applied to other coordination compounds.
含有配位键的金属配合物在生物体的许多重要生物系统中发挥着重要作用。这类配合物的例子包括含铁的血红蛋白、含镁的叶绿素和含钴的维生素B。尽管金属配合物的热力学和其他集体性质已得到充分确立，但其机械稳定性仍未得到充分探索。单分子力谱已被用于确定化学键的结构和机械性质；然而，它在配位化学领域的应用却很少。因此，在这里，我们选择了一种独特的感兴趣的分子，HA-Ru，{HA = 透明质酸，Ru = (bpy)Ru(4-pyNH)}，并对其进行单分子力谱分析，以直接研究其键断裂过程。该分子通过蓝光照射激发，令人惊讶的是，整个过程可以在不施加任何外部能量（如热或溶剂暴露）的情况下逆转。我们的结果证明了发光钌配合物恢复到其原始状态的可逆性，这一现象可以进一步应用于其他配位化合物。
