Photophysical behaviour and photodynamic activity of zinc phthalocyanines associated to liposomes
Photophysical behaviour and photodynamic activity of zinc phthalocyanines associated to liposomes
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DOI：
10.1039/c0pp00289e
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发表时间：
2011-01-01
影响因子：
3.1
通讯作者：
Lissi, Eduardo
中科院分区：
文献类型：
--
作者：
Garcia, Angelica M.;Alarcon, Emilio;Lissi, Eduardo
酞菁是一种大环化合物，可作为光敏剂用于治疗各种感染和疾病以及光动力疗法。然而，这些化合物的临床应用的一个缺点是它们形成低聚物（特别是二聚体）的强烈倾向，这种现象降低了它们作为光敏剂的效率。在本论文中，我们研究了ZnPc和ZnF16Pc在有机溶剂（THF）和脂质体制剂（DMPC、DPPC和DSPC）中的光物理和光化学性质。我们的研究结果表明，通过吸收光谱、三重态量子产率和单线态氧量子产率测量，染料掺入脂质体会降低脂质体的聚集度。此外，我们研究了脂质体制剂中两种酞菁对人宫颈癌（HeLa）细胞的光动力学活性。ZnF16Pc的光物理行为和光毒性与其聚集程度相关。二聚体不具有光活性，ZnF16Pc的光化学反应取决于作为单体存在的分数。另一方面，ZnPc在三种脂质体中的聚集最小，其光物理和光化学性质相似。然而，其体外光毒性依赖于脂质体。
Phthalocyanines are macrocyclic compounds that can be employed as photosensitizers in the treatment of various infections and diseases, as well as in photodynamic therapy. Nevertheless, a disadvantage for the clinical application of these compounds is their strong tendency to form oligomers (especially dimers), a phenomenon that reduces their efficiency as photosensitizers. In the present contribution, we have studied the photophysical and photochemical properties of ZnPc and ZnF16Pc in an organic solvent (THF) and liposomal formulations (DMPC, DPPC and DSPC). Our results show that dye incorporation into liposomes decreases its aggregation degree, as revealed by absorption spectra, triplet quantum yield, and singlet oxygen quantum yield measurements. Additionally, we studied the photodynamic activity of both phthalocyanines in liposomal formulation on human cervical carcinoma (HeLa) cells. For ZnF16Pc the photophysical behavior and phototoxicity in vitro correlate with the aggregation degree. The dimers are not photoactive and the photochemistry of ZnF16Pc depends of the fraction present as monomer. On the other hand, ZnPc aggregation is minimal and its photophysical and photochemical properties are similar in the three liposomes studied. Nevertheless, its phototoxicity in vitro is liposome dependent.