Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, Department of Chemistry, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK.
Inorg Chem. 2023 Feb 13;62(6):2672-2679. doi: 10.1021/acs.inorgchem.2c03698. Epub 2023 Jan 30.
Following electrospray ionization, it is common for analytes to enter the gas phase accompanied by a charge-carrying ion, and in most cases, this addition is required to enable detection in the mass spectrometer. These small charge carriers may not be influential in solution but can markedly tune the analyte properties in the gas phase. Therefore, measuring their relative influence on the target molecule can assist our understanding of the structure and stability of the analyte. As the formed adducts are usually distinguishable by their mass, differences in the behavior of the analyte resulting from these added species (e.g., structure, stability, and conformational dynamics) can be easily extracted. Here, we use ion mobility mass spectrometry, supported by density functional theory, to investigate how charge carriers (H, Na, K, and Cs) as well as water influence the disassembly, stability, and conformational landscape of the homometallic ring [CrF(OCBu)] and the heterometallic rotaxanes [NHRR'][CrMF(OCBu)], where M = Mn, Fe, Co, Ni, Cu, Zn, and Cd. The results yield new insights on their disassembly mechanisms and support previously reported trends in cavity size and transition metal properties, demonstrating the potential of adduct ion studies for characterizing metallosupramolecular complexes in general.
电喷雾电离后，分析物通常伴随着带电荷的离子进入气相，在大多数情况下，这是在质谱仪中进行检测所必需的。这些小的电荷载体在溶液中可能没有影响，但可以显著调节气相中分析物的性质。因此，测量它们对目标分子的相对影响可以帮助我们理解分析物的结构和稳定性。由于形成的加合物通常可以通过其质量来区分，因此这些添加物种（例如结构、稳定性和构象动力学）导致的分析物行为的差异可以很容易地提取出来。在这里，我们使用离子淌度质谱法，并辅以密度泛函理论，研究了电荷载体（H、Na、K 和 Cs）以及水如何影响同金属环[CrF(OCBu)]和杂金属轮烷[NHRR'][CrMF(OCBu)]的解组装、稳定性和构象景观，其中 M = Mn、Fe、Co、Ni、Cu、Zn 和 Cd。这些结果为它们的解组装机制提供了新的见解，并支持了先前报道的空腔大小和过渡金属性质趋势，证明了加合物离子研究在一般情况下表征金属超分子配合物的潜力。
