Transformative breakthrough in cancer phototheranostics utilizing bioinspired chemistry of polydopamine-based multifunctional nanostructures

This review mainly examines advanced PDA-based theranostic techniques for improving the image-guided treatment of cancer, including light-to-heat-based PTT, targeted drug delivery, photodynamic therapy, photo-immune therapy, and combination therapy. It also discusses the biocompatibility, safety, advantages, and prospects for theranostic PDA-based tumor therapies. [Display omitted] •PDA has beneficial physicochemical properties for cancer phototheranostics.•The method for synthesizing their multifunctional nanostructures is discussed.•Modified PDA is suitable for photothermal, photodynamic, and immune cancer therapies.•PDA’s biocompatibility, degradability, and safety for cancer phototheranostics are discussed. Polydopamine (PDA), a biocompatible and biodegradable polymer derived from mussels, exhibits highly advantageous properties for biomedical utilization such as strong adhesive capability, high photothermal conversion efficiency, and potent drug-loading capacity. Hence, PDA-based nanoparticles (NPs) have recently emerged and have actively been harnessed as the phototheranostic agent of diseases such as cancer for their targeting abilities and multifunctionalities. For the first time, this review specifically focuses on the diverse multifunctionalized PDA-based NPs for cancer phototheranostic, based on their cancer targeting for photo-based therapies such as photothermal therapy, photodynamic therapy, photoimmunotherapy, and combinational phototherapy, as well as imaging. Furthermore, we describe the diverse shapes of PDA NPs and their synthesis process involving various bonds to achieve shape-dependent multifunctionalities, thereby facilitating their role as nanocarriers in cancer phototheranostics. We also briefly introduce the recent progress in the development of PDA-based nanovaccine for future cancer therapy while focusing on the existing limitations of PDA NPs and strategies to overcome those challenges. Finally, we discuss PDA’s biocompatibility, degradability, and safety and highlight such advantages for the potential clinical use of cancer phototherapy.