Biodegradable 'smart' NPs have the potential to achieve maximum efficacy and drug availability at the desired sites, and reduce the harmful side effects for healthy tissues in tumor therapy. It is necessary to select appropriate NPs and modify their characteristics according to treatment strategies of tumor therapy.

We develop a novel route based on the solution wetting method using anodic aluminum oxide (AAO) templates to fabricate hierarchical hybrid nanostructures assembled from polystyrene-encapsulated gold nanoparticles (Au@PS NPs). Hybrid nanostructures including nanotubes and nanospheres can be reliably prepared, in which the spatial arrangement of the Au@PS NPs is determined by the pore diameters of the templates and the molecular weights of the thiolended polystyrene (PS-SH) ligands. In particular, the Rayleighinstability-driven transformation plays a key role in the formation of the hybrid nanospheres.

Polystyrene (PS) nanotubes prepared using the solvent‐vapor‐induced wetting method with anodic aluminum oxide templates are for the first time applied to study the thermal stabilities of polymer nanotubes confined in cylindrical geometries. The morphologies of the PS nanotubes and the corresponding transformed PS nanostructures driven by the Rayleigh instabilities after thermal annealing treatments are characterized by scanning electron microscopy. Morphology diagrams of the Rayleigh‐instability‐induced nanostructures for PS nanotubes prepared via the solvent‐vapor‐induced wetting method and the solution wetting method are constructed to study the differences in kinetics for samples using different wetting methods. Slower transformation kinetics for the PS samples prepared by the solvent‐vapor‐induced wetting method than those prepared by the solution wetting method are observed, indicating the better thermal stabilities and the relatively denser packings of the polymer chains in the nanopores for the PS samples prepared using the solvent‐vapor‐induced wetting method.

To achieve multifunctional materials using a single kind of ingredient or particle, it is desired to develop simple methods to prepare anisotropic nanoparticles, such as mushroom-like nanoparticles, which can be applied to many fields. Here, we investigate the wetting of polymer nanospheres on the open ends of the nanopores of anodic alumina oxide templates, which offer asymmetric wetting environments, to fabricate mushroom-like anisotropic polymer nanoparticles with controllable morphologies. These nanostructures have special dynamic behaviors in aqueous solutions. In addition, we prepare mushroom-like Janus nanoparticles by altering the fabrication processes. This work not only demonstrates a novel method to prepare anisotropic polymer nanoparticles but also provides a detailed understanding of the wetting behaviors under asymmetric environments.

The formation of polymer nanostructures confined in cylindrical nanopores via a novel selective solvent-induced reconstruction process is investigated.