Fig. 1

Chemical structures of (a) peripheral (ZnPc1) and (b) non-peripheral (ZnPc2) tetra-substituted cationic zinc phthalocyanines. (c) UV–Vis absorption spectra of ZnPc1 and ZnPc2 in DMSO and water (5 × 10 − 5 M). (d, e) Dark and PDT-induced cytotoxicity of ZnPcs on HUVECs. (f, g) PDT-induced ROS production in HUVEC. (d) PDT with ZnPc1 induced significant cytotoxicity, without affecting cell viability in the absence of light in HUVECs. In contrast, (e) PDT with the ZnPc2 molecule caused a dose-dependent cytotoxicity, without affecting cell viability in the absence of light. PDT light dose: 20 joules.cm⁻². Results are shown as means ± SD of three independent experiments. *p < 0.05, **p < 0.01 and ***p < 0.001. PDT light dose: 20 joules.cm⁻². Results are means ± SD of three independent experiments. *p < 0.05, **p < 0.01 and ***p < 0.001. PDT light dose: 20 joules.cm⁻².