Laser-Excited Lanthanide Ion Luminescence in Chemistry and Biophysics ,

该项目将由生物物理项目和无机、生物无机和有机金属化学项目共同支持。该项目的重点是在化学和生物物理学方面开发有关溶液中单个金属环境的信息，这些信息可以从激光激发镧系金属离子铽（III）和铕（III）产生的发光中获得。重要的生物学信息，如血蛋白中钙离子结合位点之间的距离，可以从这些镧系离子取代天然金属离子时的发光研究中获得。激光激发镧系离子发光技术将进一步发展，以确定测量的发光参数（强度、频率、寿命、分裂）可用于获取有关存在的不同物种的数量、Eu（III）周围配体上的总电荷、离子的位置对称性等信息。配位水分子的数量，能量转移速率和配体交换动力学。研究发光镧系离子与溶液中各种自由扩散的无机受体离子之间的能量转移，以了解共振能量转移的机制。将探讨溶剂对与大分子结合的Ln（III）离子的可及性，并评估使用Eu（III）发光作为不同构象的DNA与金属离子相互作用的探针。t-RNA的结构，其金属离子结合特性，以及与靶分子的相互作用也将使用这些方法进行探索。对模型膜系统（磷脂双层囊泡）的研究将建立金属离子与这些系统的基本相互作用，并允许研究离子载体介导的金属离子运输。将探讨Eu(III)-羟基的基本配位化学和几种具有潜在应用价值的新型螯合剂，如离子载体、核磁共振成像剂和免疫分析标记。合成了一类新的大环配体冠亚砜，并探讨了与Ln（III）离子的络合作用。

This project will be supported jointly by the Biophysics Program and the Inorganic, Bioinorganic and Organometallic Chemistry Program. The focus of the project is the exploitation in chemistry and biophysics of the information about individual metal environments in solution which can be obtained from the luminescence which occurs as a result of laser excitation of the lanthanide metal ions terbium(III) and europium(III). Imporant biological information, such as the distances between calcium ion binding sites in blood proteins, can be obtained from studies of the luminescence of these lanthanide ions when they are substituted for the native metal ions. Laser-excited lanthanide ion luminescence techniques will be developed further to determine the extent to which measured parameters of the luminescence (intensities, frequencies, lifetimes, splittings) can be used to obtain information about the number of distinct species present, the total charge on the ligands surrounding Eu(III), the site symmetry of the ion, the number of coordinated water molecules, energy transfer rates, and ligand exchange kinetics. Energy transfer between luminescent lanthanide ions and various freely-diffusing inorganic acceptor ions in solution will be investigated to provide an understanding of the mechanism of resonant energy transfer. The accessability of solvent to Ln(III) ions bound to macromolecules will be probed, and the use of Eu(III) luminescence as a probe of the interaction of DNA in its various conformations with metal ions will be assessed. The structure of t-RNA, its metal ion binding characteristics, and interactions with target molecules will be explored also using these methods. An investigation of model membrane systems (phospholipid bilayer vesicles) will establish the basic interactions of metal ions with these systems and allow the study ofionophore-mediated transport of metal ions. The basic coordination chemistry of Eu(III)-hydroxo species and several novel chelating agents with potential applications as ionophores, nmr imaging agents and immunoassay labels will be explored. A new class of macrocyclic ligand, crown sulfoxides, will be synthesized and complexation with Ln(III) ions explored.