CHAPTER 4:Hydrophilic Ir(iii) Complexes for In vitro and In vivo Oxygen Imaging
CHAPTER 4:Hydrophilic Ir(iii) Complexes for In vitro and In vivo Oxygen Imaging
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第 4 章：用于体外和体内氧成像的亲水性 Ir(iii) 配合物
DOI：
10.1039/9781788013451-00071
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
S. Tobita
中科院分区：
文献类型：
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作者：
Toshitada Yoshihara;Y. Hirakawa;M. Nangaku;S. Tobita
铱（iii）配合物被有效地吸收到细胞中，并发出氧依赖性磷光，这可以在体内氧测量中利用。在这里，我们新合成了亲水性Ir（iii）配合物BTP-PEGn（n = 12，24和48）和PPY-PEG 24，它们在Ir（btp）3（btp =苯并噻吩基吡啶）的btp配体上具有不同链长的聚乙二醇（PEG）基团，在Ir（ppy）3（ppy =苯基吡啶）的ppy配体上具有24个单元长。BTP-PEGn和PPY-PEG 24可溶于水，分别发射红色和绿色磷光，其被水中的氧气有效地猝灭。通过稳态和时间分辨磷光测量确定了这些配合物的光物理性质。在配体上引入PEG链可显著抑制发色团与人血清白蛋白在水中的相互作用。HT-29细胞渗透实验表明，这些复合物的细胞摄取效率非常低。通过经由尾静脉向小鼠施用BTP-PEG 48来实现血管内染色。通过荧光和磷光寿命成像显微镜（FLIM/PLIM）获得肾皮质的寿命图像。使用BTP-PEG 48获得的PLIM图像清楚地显示了肾小管周围毛细血管和泌尿空间，并且根据寿命值评估了这些空间的氧水平。
Ir(iii) complexes are efficiently taken up into cells and emit oxygen-dependent phosphorescence, which can be exploited in in vivo oxygen measurements. Here, we newly synthesized the hydrophilic Ir(iii) complexes BTP-PEGn (n = 12, 24 and 48) and PPY-PEG24, which bear polyethylene glycol (PEG) groups of different chain lengths on the btp ligand of Ir(btp)3 (btp = benzothienylpyridine) and 24 units long on the ppy ligand of Ir(ppy)3 (ppy = phenylpyridine). BTP-PEGn and PPY-PEG24 were soluble in water and emitted red and green phosphorescence, respectively, that was efficiently quenched by oxygen in water. The photophysical properties of these complexes were determined by steady-state and time-resolved phosphorescence measurements. Introduction of a PEG chain onto the ligand significantly inhibited the interaction of the chromophores with human serum albumin in H2O. Cell permeation experiments using HT-29 cells showed that the cellular uptake efficiencies of these complexes are very low. Intravascular staining was achieved by administering BTP-PEG48 to mice via the tail vein. Lifetime images of the renal cortex were obtained by fluorescence and phosphorescence lifetime imaging microscopy (FLIM/PLIM). The PLIM images obtained using BTP-PEG48 clearly visualized the peritubular capillaries and urinary space, and the oxygen levels of these spaces were evaluated from the lifetime values.