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Large-scale urchin-like iron hydroxide and oxide nanostructures were self-assembled through a low-temperature hydrothermal process assisted by two-way phase transition under sonication. The as-obtained iron hydroxide and oxide nanomaterials were used as adsorbents in waste-water treatment, and showed very good ability to remove organic pollutants.

Various nanoparticles are used to fabricate innovative systems for drug encapsulation and cancer therapy. In this paper, the hierarchical core-shell nanostructures composed of gold nanoparticles and poly(dimethylsiloxane)-poly(ethylene glycol) (PDMS-PEG) block copolymers are fabricated via a hydrosilylation reaction. The obtained gold/copolymer nanocomposites display a desired amphiphilic property and can be well-dispersed in water when the PEG blocks are long enough. The hydrophobic drug hypocrellin B (HB) can be encapsulated into these water-dispersible nanocomposites based on the hydrophobic-hydrophobic interaction between HB molecules and PDMS segments. The gold/copolymer nanocomposites loaded with HB show a rational anticancer ability in the photodynamic therapy although the gold/copolymer nanocomposites without drug also have a little cytotoxicity. Such hierarchically structured core-shell nanocomposites can be considered as water-dispersible nanotanks for hydrophobic drugs in the development of multifunctional biodelivery systems.

A facile method is reported to manipulate a diphenylalanine peptide into hierarchically ordered structures with interesting peony-like flower morphology in the organic solvent tetrahydrofuran. The flowers formed in THF and showed, by scanning electron microscopy, that they are actually flake-built spherical aggregations, while the aggregations of FF that formed in other chosen organic solvents, such as DMSO and pyridine, show dispersive flakes. The building of the flower-like architectures is correlated to a nonclassical crystallization pathway. The similarity between the as-obtained peptide mesocrystals formed in different solvents has been investigated and discussed. Due to the roughness of the hierarchical peptide assemblies, an antiwetting surface is readily constructed with a low surface free energy fluoroalkylsilane.

In this study, a capsule/lipid composite system has been developed for targeted delivery of small molecular drugs (daunorubicin hydrochloride, DNR) to cancer cells. The lipid coating not only provides a sealed barrier to prevent the leakage of the encapsulated drugs, but also can be used as a means to attach biological functionality to capsule surfaces. A neoglycolipid incorporated into the supported lipid membrane has shown high affinity in lectin binding studies (concanavalin A), while a folate-linked lipid in the lipid membrane provides a functional capacity to target cancer cells (MCF-7). Folate-targeted capsules are much more efficient than the non-targeted capsules in delivering DNR to MCF-7 cells. The system provides a way to create a biomimetic delivery vehicle for the effective and selective targeting of drugs.

Polyaniline tower-shaped hierarchical nanostructures were prepared through an unusual route by a limited hydrothermal reaction. The evolution of these superstructures was investigated and the relative mechanism was discussed. This growth process is quite different from that of traditional inorganic layer-like superstructures. The room temperature conductivity of the superstructures was about 10−2 to10−1S cm−1. It may pave a new way for obtaining other conductive polymers with similar superstructures.

Biodegradable and multifunctionalized nanotubes are of special interest since they can be applied to biological systems including bioseparation, biocatalysis and biomolecule delivery. In this paper, magnetic polypeptide nanotubes were fabricated through the layer-by-layer (LbL) assembly of poly-L-lysine hydrochloride (PLL), poly-L-glutamic acid (PGA) and magnetic nanoparticles within the inner pores of polycarbonate templates with subsequent removal of the templates. The wall thickness and inner diameter of as-prepared nanotubes can be tuned by changing the assembled layers, and the length and outer diameter are dependent on the used templates. These magnetic polypeptide nanotubes can be used as a DNA carrier and manipulated under magnetic force.

Multi-functional mesoporous silica nanoparticles (MSNs) coated with poly(N-isopropylacrylamide) (PNIPAM) composite nanomaterials have been designed and synthesized by atom transfer radical polymerization (ATRP) on the surface of MSN through the “grafting-from” approach. Such materials not only provide porous cores which can act as suitable reservoirs, but also possess thermosensitive polymer shells which can entrap hydrophilic guest molecules, like FITC, into the cores upon varying the temperature. The materials can easily carry guest molecules into human breast carcinoma cells (MCF-7) and show little cytotoxicity to the cells. It is demonstrated that such MSN@PNIPAM materials can be applied in biological systems for cellular imaging or as biosensors.

A hydrophobic photodynamic therapy drug, hypocrellin B (HB), was accumulated in water-solubilized natural polyelectrolyte microcapsules. The HB can be effectively encapsulated, delivered and subsequently taken up by cancer cells. These intracellular HB-loaded microcapsules show biocompatibility under darkness and high cytotoxicity after irradiation which provides the possibility of controlled delivery and release of drugs.