Cole Houston D, Vali Abbas, Roque John A, Shi Ge, Talgatov Alisher, Kaur Gurleen, Francés-Monerris Antonio, Alberto Marta E, Cameron Colin G, McFarland Sherri A
Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States.
Institut de Ciència Molecular, Universitat de València, 46071 València, Spain.
Inorg Chem. 2024 May 27;63(21):9735-9752. doi: 10.1021/acs.inorgchem.3c04382. Epub 2024 May 10.
A series of Ru(II) complexes incorporating two 4,4'-bis(trifluoromethyl)-2,2'-bipyridine (4,4'-btfmb) coligands and thienyl-appended imidazo[4,5-][1,10]phenanthroline (IP-T) ligands was characterized and assessed for phototherapy effects toward cancer cells. The [Ru(4,4'-btfmb)(IP-T)] scaffold has greater overall redox activity compared to Ru(II) polypyridyl complexes such as [Ru(bpy)]. - have additional oxidations due to the T group and additional reductions due to the 4,4'-btfmb ligands. - also exhibit T-based reductions. exhibits two oxidations and eight reductions within the potential window of -3 to +1.5 V. The lowest-lying triplets (T) for - are metal-to-ligand charge-transfer (MLCT) excited states with lifetimes around 1 μs, whereas T for - is longer-lived (∼20-24 μs) and of significant intraligand charge-transfer (ILCT) character. Phototoxicity toward melanoma cells (SK-MEL-28) increases with , with having a visible EC value as low as 9 nM and PI as large as 12,000. and retain some of this activity in hypoxia, where has a visible EC as low as 35 nM and PI as high as 2900. Activity over six biological replicates is consistent and within an order of magnitude. These results demonstrate the importance of lowest-lying ILCT states for phototoxicity and maintaining activity in hypoxia.
一系列包含两个4,4'-双（三氟甲基）-2,2'-联吡啶（4,4'-btfmb）共配体和噻吩基取代的咪唑并[4,5 - ][1,10]菲咯啉（IP - T）配体的钌（II）配合物被表征，并评估了其对癌细胞的光疗效果。与钌（II）多吡啶配合物如[Ru(bpy)]相比，[Ru(4,4'-btfmb)(IP - T)]支架具有更高的整体氧化还原活性。由于T基团存在额外的氧化，并且由于4,4'-btfmb配体存在额外的还原。还表现出基于T的还原。在 - 3至 +1.5 V的电位窗口内表现出两次氧化和八次还原。对于 - 而言，最低能量的三重态（T）是金属到配体电荷转移（MLCT）激发态，寿命约为1 μs，而对于 - 而言，T寿命更长（约20 - 24 μs）且具有显著的配体内电荷转移（ILCT）特征。对黑色素瘤细胞（SK - MEL - 28）的光毒性随着 增加， 具有低至9 nM的可见EC值和高达12,000的PI值。 在缺氧条件下保留了部分这种活性，其中 具有低至35 nM的可见EC值和高达2900的PI值。六个生物学重复的活性是一致的且在一个数量级内。这些结果证明了最低能量的ILCT态对光毒性和在缺氧条件下维持活性的重要性。
