Metallated porphyrin-doped conjugated polymer nanoparticles for efficient photodynamic therapy of brain and colorectal tumor cells

Abstract

Aim: Assess biocompatibility, uptake and photodynamic therapy (PDT) mechanism of metallated porphyrin doped conjugated polymer nanoparticles (CPNs) in human brain and colorectal tumor cells and macrophages.

Materials & methods: CPNs were developed employing 9,9-dioctylfluorene-alt-benzothiadiazole, an amphiphilic polymer (PS-PEG-COOH), and platinum octaethylporphyrin. T98G, SW480 and RAW 264.7 cell lines were exposed to CPNs to assess uptake and intracellular localization. Additionally, a PDT protocol using CPNs was employed for the in vitro killing of cancer and macrophage cell lines.

Results & conclusion: CPNs were well incorporated into glioblastoma and macrophage cells with localization in lysosomes. SW480 cells were less efficient incorporating CPNs with localization in the plasma membrane. In all cell lines PDT treatment was efficient inducing oxidative stress that triggered apoptosis.

Keywords: ROS; apoptosis; brain tumor; colorectal tumor; conjugated polymer nanoparticles; metallated porphyrin; photodynamic therapy.