Photodynamic Therapy with Conjugated Polymer Nanoparticles: Recent Advances and Therapeutic Considerations

Many types of cancers require elevated levels of Reactive Oxygen Species (ROS) for uncontrolled proliferation. However, this also makes tumor cells more susceptible to ROS induced cell death by additional oxidative stress caused by external stimuli. By selectively targeting cancer cells and tumors that exhibit high levels of ROS with nanotechnology-based materials to trigger further elevation of ROS therapeutic possibilities become available. Specifically, light-activated treatment through Photodynamic Therapy (PDT) has been demonstrated as a feasible approach with Photophryn as the leading FDA approved sensitizer. However, such small molecule sensitizers do still have significant hurdles to overcome, including poor solubility, non-targeted delivery, and low absorption of light. In this mini review, recent advances in the development of Conjugated Polymer Nanoparticles (CP-NPs) solving these issues are discussed, including amplified ROS generation, tumor targeting, theranostic capabilities, and multimodal CP-NPs. We also give an outlook towards further needs in CP-NP development for clinical application.