Polyphenol-based
hollow nanoparticles have exhibited intriguing
properties in drug delivery, catalysis, and energy storage, and the
open-mouthed (bowl-shaped) structure is supposed to improve the performance
of the nanoparticles by increasing the accessibility of the inner
surface and the cavity. Up to now, cationic polymers, metal ions,
and sacrificial templates are generally applied in the preparation
of the polyphenol-based hollow nanoparticle, and these polyphenols
are usually confined to tannin acid and lignin. Seeking for the novel
assembly strategy with a wide selection of polyphenolic compounds
would open a new horizon for the design, preparation, and applications
of polyphenol-based functional materials. In this study, polyphenol
nanoparticles with bowl-shaped structure were efficiently prepared
through the polymerization-induced self-assembly of tea polyphenols
in a few minutes. The formation mechanism was proposed on the basis
of a series of TEM images revealing the morphology evolution process.
The nanoparticles with good stability in carbonization process are
candidates for bowl-shaped carbon spheres. These nanoparticles exhibit
potent radical scavenging capacity, anticancer activity, high adsorption
capacity of guest molecules (DOX and methylene blue), and pH-dependent
release property, with promising use as active delivery systems. Moreover,
the present polyphenol assembly strategy provides inspiration for
fundamental studies on structure–property–function relationship
of polyphenol-based materials.