Water-soluble cyclometalated platinum(II) and iridium(III) complexes: synthesis, tuning of the photophysical properties, and in vitro and in vivo phosphorescence lifetime imaging

作者：Solomatina Anastasia I; Su Shih Hao; Lukina Maria M; Dudenkova Varvara V; Shcheslavskiy Vladislav I; Wu Cheng Ham; Chelushkin Pavel S; Chou Pi Tai^*; Koshevoy Igor O; Tunik Sergey P^*

来源：RSC Advances, 2018, 8(31): 17224-17236.

DOI：10.1039/c8ra02742k

This paper presents synthesis and photophysical investigation of cyclometalated water-soluble Pt(u) and Ir(III) complexes containing auxiliary sulfonated diphosphine (bis(diphenylphosphino)benzene (dppb), P boolean AND P*) ligand. The complexes demonstrate considerable variations in excitation (extending up to 450 nm) and emission bands (with maxima ranging from ca. 450 to ca. 650 nm), as well as in the sensitivity of excited state lifetimes to molecular oxygen (from almost negligible to more than 4-fold increase in degassed solution). Moreover, all the complexes possess high two-photon absorption cross sections (400-500 GM for Pt complexes, and 600-700 GM for Ir complexes). Despite their negative net charge, all the complexes demonstrate good uptake by HeLa cells and low cytotoxicity within the concentration and time ranges suitable for two-photon phosphorescence lifetime (PLIM) microscopy. The most promising complex, [(PPY)(2)Ir(sulfo-dppb)] (Ir1*), upon incubation in HeLa cells demonstrates two-fold lifetime variations under normal and nitrogen atmosphere, correspondingly. Moreover, its in vivo evaluation in athymic nude mice bearing HeLa tumors did not reveal acute toxicity upon both intravenous and topical injections. Finally, Id* demonstrated statistically significant difference in lifetimes between normal tissue (muscle) and tumor in macroscopic in vivo PLIM imaging.

• 出版日期2018