A triphenylamine functionalized photosensitizer as a promising candidate for osteosarcoma cancer phototheranostics

Abstract

Osteosarcoma is a malignant tumor affecting an increasing number of individuals worldwide. In this paper, a triphenylamine (TPA) functionalized photosensitizer DPPTPA was synthesized for cancer theranostics. The conjugation of TPA onto the DPP moiety not only prolongs the absorbance to the near-infrared region (NIR) but also adds to the phototoxicity of DPPTPA. DPPTPA NPs prepared by the nanoprecipitation method exhibit considerable cytotoxicity under laser irradiation, with a half-maximal inhibitory concentration (IC₅₀) of 4.38 μg mL⁻¹ for inhibiting HOS cell proliferation. The green channel of a confocal laser scanning microscope confirmed efficient cellular uptake. Furthermore, in vivo studies indicated that tumor proliferation was suppressed effectively upon laser irradiation. In contrast, the tumor volume in the non-irradiation group remained like that in the control group, indicating high phototoxicity and low dark toxicity. The results demonstrate the potential of DPPTPA nanoparticles for cancer phototheranostics.