Innovations and challenges of polyphenol-based smart drug delivery systems

Polyphenols, as widely existing natural bioactive products, provide a vast array of advanced biomedical applications attributing to their potential health benefits that linked to antioxidant, anti-inflammatory, immunoregulatory, neuroprotective, cardioprotective function, etc. The polyphenol compounds could dynamically interact and bind with diverse species (such as polymers, metal ions, biomacromolecules, etc.) via multiple interactions, including hydrogen bond, hydrophobic, π–π, and cation–π interactions due to their unique chemical polyphenolic structures, providing far-ranging strategies for designing of polyphenol-based vehicles. Natural polyphenols emerged as multifaceted players, acting either as inherent therapeutics delivered to combat diverse diseases or as pivotal assemblies of drug delivery vehicles. In this review, we focused on the rational design and application of metal-phenolic network (MPN) based delivery systems, polyphenol-based coating films, polyphenol hollow capsules, polyphenol-incorporated hydrogels, and polymer-polyphenol-based nanoparticles (NPs) in various diseases therapeutic, including cancer, infection, cardiovascular disease, neurodegenerative disease, etc. Additionally. the versatility and mechanisms of polyphenols in the field of biomacromolecules (e.g., protein, peptide, nucleic acid, etc.) delivery and cell therapy have been comprehensively summarized. Going through the literature review, the remaining challenges of polyphenol-containing nanosystems need to be addressed are involved, including long-term stability, biosafety in vivo, feasibility of scale-up, etc., which may enlighten the further developments of this field. This review provides perspectives in utilizing natural polyphenol-based biomaterials to rationally design next generation versatile drug delivery system in the field of biomedicine, which eventually benefits public health.