Photodynamic therapy (PDT) is a promising cancer treatment that can be implemented using various agents. The conventional photosensitizer Al (III) phthalocyanine chloride tetrasulfonic acid (Pc) has limitations of selectivity in tumor targeting, low affinity to cancer cells, and low two-photon absorption. This study presents a novel photosensitizer FA-TiO₂-Pc, which has the TiO₂ nanoparticle conjugated with a tumor targeting agent of folic acid (FA), and Pc. FA-TiO₂-Pc possessed high targeted photodynamic therapeutic activity and excellent biocompatibility. This promising photosensitizer showed high therapeutic drug efficiency in vitro at a low concentration dose and short incubation time under one-photon excitation (OPE). In vivo, when treated with a low dose of FA-TiO₂-Pc and low light irradiation, the tumor growth was depressed in mice bearing HeLa xenograft tumors with minimal side effects. In addition, the two-photon absorption of FA-TiO₂-Pc was also enhanced compared to Pc, proving that FA-TiO₂-Pc system has a great potential to be used for the therapy of the folate receptor positive cancer cells in both OPE-PDT and two-photon excitation (TPE)-PDT agents.

光动力疗法（PDT）是一种有前途的癌症治疗方法，可以使用多种药物实施。常规的光敏剂Al（III）酞菁氯化物四磺酸（Pc）在肿瘤靶向中的选择性，对癌细胞的低亲和力和低的两个光子吸收方面具有局限性。这项研究提出了一种新型的光敏剂FA-TiO ₂ -Pc，它具有与叶酸（FA）和Pc的肿瘤靶向剂共轭的TiO ₂纳米颗粒。FA-的TiO ₂-Pc具有高靶向光动力治疗活性和优异的生物相容性。这种有前途的光敏剂在低浓度剂量下在体外具有很高的治疗药物效率，并且在单光子激发（OPE）下孵育时间短。在体内，当用低剂量的FA-TiO ₂ -Pc和弱光照射治疗时，荷HeLa异种移植肿瘤的小鼠的肿瘤生长受到抑制，副作用最小。另外，与Pc相比，FA-TiO ₂ -Pc的双光子吸收也得到增强，证明FA-TiO ₂ -Pc系统具有巨大的潜力可用于治疗叶酸受体阳性癌细胞。 OPE-PDT和两光子激发（TPE）-PDT剂。