Boosting the photosensitization type I process will enhance the phototherapy efficacy because the superoxide radicals (O₂⁻) generated during type I process are more toxic than the singlet oxygen (¹O₂) in type II process. Herein, [Ru(Hdtza)(phen)₂][PF₆] (1) and [Ru(pytz)(phen)₂][PF₆] (2) (phen = 1,10-phenanthroline) based on two nitrogen-rich tetrazole ligands, di(2H-tetrazol-5-yl) amine (H₂dtza) and 5-(2-pyridyl)tetrazole (Hpytz) have been developed for photodynamic therapy (PDT) against lung cancer, respectively. Nanoprecipitation was used to prepare the nanoparticles (NPs) of both compounds. [Ru(Hdtza)(phen)₂][PF₆] NPs mainly undergo an electron transfer process to generate O₂⁻ while [Ru(pytz)(phen)₂][PF₆] the direct energy transfer to produce ¹O₂, which is responsible for the higher phototoxicity of [Ru(Hdtza)(phen)₂][PF₆] NPs (IC₅₀ ~ 4.8 μg/mL) than that of [Ru(pytz)(phen)₂][PF₆] NPs (IC₅₀ ~ 13.6 μg/mL) on human lung cancer cells (A549). Furthermore, in vivo study indicates that the tumor proliferation of nude mice can be effectively inhibited with the help of laser when the mice were injected with [Ru(pytz)(phen)₂][PF₆] NPs. This work may provide a simple strategy to design type I photosensitizers for enhanced photodynamic therapy.

增强光敏I型过程将提高光疗效果，因为I型过程中产生的超氧自由基（O ₂ ^-）比II型过程中的单线态氧（¹ O ₂）毒性更大。这里，[Ru(Hdtza)(phen) ₂ ][PF ₆ ] ( 1 ) 和[Ru(pytz)(phen) ₂ ][PF ₆ ] ( 2 ) (phen = 1,10-菲咯啉) 基于两个氮-富四唑配体，二(2H-四唑-5-基)胺(H ₂dtza) 和 5-(2-吡啶基) 四唑 (Hpytz) 已分别用于针对肺癌的光动力疗法 (PDT)。纳米沉淀用于制备两种化合物的纳米颗粒 (NPs)。[Ru(Hdtza)(phen) ₂ ][PF ₆ ] NPs主要通过电子转移过程产生O ₂ ^-而[Ru(pytz)(phen) ₂ ][PF ₆ ]直接能量转移产生¹ O ₂，这导致 [Ru(Hdtza)(phen) ₂ ][PF ₆ ] NPs (IC ₅₀  ~ 4.8 μg/mL) 的光毒性高于[Ru(pytz)(phen) ₂ ][PF ₆ ]纳米颗粒（IC₅₀  ~ 13.6 μg/mL) 对人肺癌细胞 (A549)。此外，体内研究表明，当裸鼠注射[Ru(pytz)(phen) ₂ ][PF ₆ ] NPs时，激光可以有效抑制裸鼠的肿瘤增殖。这项工作可能为设计用于增强光动力疗法的 I 型光敏剂提供一种简单的策略。