Development of Molybdenum and Tungsten Cluster Complexes for Singlet Oxygen Generation and Biological Implications

由于其固有的光物理性质，含有[{M6I8}L6]2-簇（M = Mo， W）和6个末端配体(L)的金属碘化物配合物在发光器件、染料敏化太阳能电池、光学氧传感器和敏化剂等方面的潜在应用引起了人们的极大兴趣。我们在这个项目中的德国-俄罗斯联合财团的研究将涉及基于M = Mo， W的八面体[M6I8]簇核的簇化合物的制备和改性，包括开发新的碘化钨簇，如[M5I8]方锥体簇核，[M5M´I8]混合金属簇和[M5I8C]簇与覆盖非金属原子(C)。配体(L)取代反应在我们的研究小组中已经建立了八面体[{M6I8}L6]2-簇的取代反应，以产生含有混合配体偏离的[{M6I8}L6]2-簇的化合物。通过对化合物的制备和光化学研究，深入了解这些材料的性质，强调光致发光和单线态氧形成下的发光猝灭。开发稳定的Mo和W簇化合物，能够在固态和溶液中产生单线态氧，被认为是重要的，因为它涉及到正在考虑的化合物的独特潜力，在生物学意义上有用，但也有其他好处。团簇化合物的性质，部分具有高化学稳定性（取决于配体的类型），以及它们在发光和单线态氧生成方面具有可验证的高量子产量的潜力，因此不仅在制备化学而且在光谱学，物理学和生物学的某些领域都是一个挑战。这种化合物的建立对于未来卫生领域的应用可能是独一无二的，因为它们能够在各种介质（固体、溶液和基质）的视觉光照射条件下产生单线态氧。为了实现这一目标，也为了对这类化合物有更深入的理论理解，我们开发和优化了簇化合物，并根据几个标准调整了它们的性质，如在不同介质中的溶解度和化学稳定性、光化学稳定性和单线态氧量子产率。我们将制备水溶性团簇，将其固定在基质中或表面，研究其光物理性质，并研究其在生物环境中的活性，这意味着团簇化合物在生物相容性基质上的固定是重要的。在这些研究过程中，我们将确定、分析和了解团簇化合物的外部先决条件，与高单线态氧生成的（团簇到O2）能量转移条件有关。

Due to their intrinsic photophysical properties, metal iodide complexes containing [{M6I8}L6]2- clusters with M = Mo, W and six terminal ligands (L) have attracted considerable interest for their prospective applications as light-emitting devices, dye-sensitized solar cells, optical oxygen sensors, and sensitizers. Studies of our joint German-Russian consortium within this project will involve the preparation and modification of cluster compounds based on the octahedral [M6I8] cluster core with M = Mo, W, including the development of new tungsten iodide clusters, such as [M5I8] square pyramidal cluster core, [M5M´I8] mixed metal clusters, and [M5I8C] clusters with a capping non-metal atom (C). Ligand (L) substitution reactions are well-established in our research groups for octahedral [{M6I8}I6]2- clusters, to yield compounds with [{M6I8}L6]2- clusters including deviates with mixed ligands. Compounds are prepared and studied photochemically to get a deeper understanding regarding the properties of these materials emphasizing photoluminescence, and luminescence quenching under formation of singlet oxygen. The development of stable Mo and W clusters compounds, capable for singlet oxygen generation in solid state and in solution is considered important because it involves a distinguished potential of compounds under consideration, useful in biological implications but also for other benefit. The properties of cluster compounds, with in part high chemical stability (depending on the type of ligand) and their verifiable potential of exceptional high quantum yields for luminescence and singlet oxygen generation is exceptional and thus a challenge not only in preparative chemistry but also in some fields of spectroscopy, physics, and biology. The establishment of such compounds may be unique for future applications in hygiene, due to their capability of singlet oxygen generation under visuals light irradiation condition in various media (solid, solution, and in matrices). For this goal and for a deeper theoretical understanding of such compounds we develop and optimize cluster compounds and tune their properties related to several criteria, such as solubility and chemical stability in different media, photochemical stability and singlet oxygen quantum yields. We will prepare water soluble clusters, immobilized into, or on the surface of matrices, study photophysical properties, and investigate their activity in biological environments, meaning that an immobilization of cluster compounds on biocompatible matrices is important. In course of these studies we will determine, analyze and learn about external preconditions of cluster compounds, related to the (cluster to O2) energy transfer conditions for high singlet oxygen generation.