Polydopamine (PDA) is a promising biomaterial derived from the self-polymerization of dopamine under alkaline conditions. With various reactive functional groups on the surface, PDA supports facile modification with thiol- and amine-containing molecules and coating on different types of materials. Owing to the biocompatibility, high cellular uptake, low cytotoxicity, and fluorescence quenching ability, PDA-based nanomaterials have found a wide range of biomedical applications, such as bioimaging, molecular diagnostics, gene delivery, controlled drug release, photothermal therapy, cancer theranostics, and antimicrobials. However, their limited biodegradability greatly obstructs their clinical translation. We have recently developed a series of polydopamine-based nanosystems with thioketal, disulfide, or diazo linkages, which are cleavable by reactive oxygen species, thiols, and reducing agents, respectively. These biodegradable nanoplatforms can be used to encapsulate a chemotherapeutic drug or photothermal agent, immobilize a photosensitizer, and incorporate a tumor-targeting peptide to form tumor-directed and stimuli-responsive nanodrugs for synergistic chemo and photodynamic therapy against cancer. The results will be reported and discussed in this presentation.
This work was supported by a General Research Fund from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. 14306320).