报告题目：CationicIridium(III) and Ruthenium(II) Complexes as Broadband Reverse SaturableAbsorbers and/orin vitroTheranostic Photodynamic Therapy (PDT)Reagents
报告人：Wenfang Sun教授(James A. Meier Senior Professor, NorthDakota State University, USA)
报告时间：2017年6月16日(周五)上午10：00 – 11：00
Abstract：Iridium(III) and ruthenium(II) complexes with moderate ground-state absorption in thevisible to the near-IR region, long-lived triplet excited states and strongtriplet excited-state absorption, and near-IR emission are promising agents forbroadband reverse saturable absorption (RSA) and photodynamic therapy as wellas bioimaging. The synthesis, photophysics, reverse saturable absorption,andin vitrophotodynamic therapeutic effect and bioimaging of twoseries of cationic biscyclometalated Ir(III) complexes with extendedp-conjugationon the diimine ligand and/or the cyclometalating ligands and one series of Ru(II)complexes with trisdiimine ligands are reported. Most of the complexespossess moderate charge-transfer absorption bands between 400 and 600 nm; andthese bands are extended to 800 nm when thep-conjugation of thecyclometalating ligands increases. They are all emissive in the red tothe NIR region in solutions at room temperature. The nature and energiesof the lowest singlet and emitting triplet excited states are primarilyinfluenced by the degree ofp-conjugation of the ligands. Most of the complexes cangenerate singlet oxygen efficiently, and exhibit a photodynamic therapeuticeffect upon visible or red light activation, with one of the Ir(III) complexespossessing the largest phototherapeutic index reported to date (> 400) forIr(III) complexes upon white light activation. Interactions with DNAsuggest that other mechanism of action may be at play for the photosensitizingeffect. These complexes also produce strong intracellular luminescencethat highlights their potential as theranostic PDT agents. In addition,many of the complexes exhibit strong RSA for ns laser pulses at 532 nm, and theRSA performance is influenced by the nature of the diimine and/orcyclometalating ligands.