A new series of unsubstituted and halogenated silicon(IV) phthalocyanines with two axial poly(ethylene glycol) (PEG) chains having an average molecular weight of 550 or 750 (PEG550 or PEG750) have been synthesised by treating the corresponding silicon phthalocyanine dichloride with PEG methyl ether in the presence of NaH. The compounds have been unambiguously characterised with 1H NMR and MALDI-TOF mass spectrometry. With two bulky polymeric substituents, the compounds are essentially non-aggregated in common organic solvents. The longer PEG750 chain enhances the hydrophilicity of the phthalocyanine ring and is more effective to prevent aggregation and fluorescence quenching by Cu(OAc)2. Substitution with heavier halogen atoms on the periphery of the ring leads to a reduction in fluorescence emission and an increase in singlet oxygen quantum yield, as a result of heavy atom effect. The compounds Si(PcX8)(PEG750)2
[X = H (4b), Cl (4c), Br (4d)] are photocytotoxic towards HepG2 human hepatocarcinoma cells and J774 mouse mammary tumour cells. Although halogenation results in an increase in singlet oxygen quantum yield, the general photocytotoxicity follows the order 4b > 4d > 4c. This can be attributed to the opposite effect of aggregation, which follows the order 4a < 4b < 4c in the growth medium. The interactions of 4b–d with bovine serum albumin (BSA) have also been investigated by a fluorescence quenching method and a non-covalent conjugate of 4b and BSA has been prepared. Conjugation with BSA leads to a higher photocytotoxicity against J774 cells, which have a BSA-loving macrophage origin.
通过在 NaH 存在下用 P
EG 甲醚处理相应的二
氯化
硅酞菁,合成了一系列新的未取代和卤化
硅(IV)
酞菁,这些
酞菁具有两条轴向聚
乙二醇(P
EG)链,其平均分子量为 550 或 750(P
EG550 或 P
EG750)。这些化合物已通过 1H NMR 和 MALDI-TOF 质谱法明确表征。由于含有两个大分子取代基,这些化合物在普通有机溶剂中基本上不会聚集。较长的 P
EG750 链增强了
酞菁环的亲
水性,能更有效地防止聚集和 Cu(OAc)2 的荧光淬灭。由于重原子效应,在环的外围取代较重的卤素原子会导致荧光发射的减少和单线态氧量子产率的增加。化合物 Si(PcX8)(P
EG750)2 [X = H (4b)、Cl (4c)、Br (4d)]对 HepG2 人肝癌细胞和 J774 小鼠乳腺肿瘤细胞具有光毒性。虽然卤化会导致单线态氧量子产率的增加,但一般的光毒性遵循 4b > 4d > 4c 的顺序。这可归因于聚集的相反效应,即在生长介质中聚集的顺序为 4a < 4b < 4c。我们还通过荧光淬灭法研究了 4b-d 与牛血清白蛋白(BSA)的相互作用,并制备了 4b 与 BSA 的非共价共轭物。与 BSA 的共轭作用使 4b-d 对 J774 细胞具有更高的光毒性,因为 J774 细胞起源于喜欢
BSA 的巨噬细胞。