This Review highlights recent progress towards controlling the movement of fuel-driven nanomotors and discusses the challenges and opportunities associated with the achievement of such nanoscale motion control. Regulating the movement of artificial nanomotors often follows nature's elegant and remarkable approach for motion control. Such control of the movement of synthetic nanomotors is essential for performing various tasks and diverse applications.

Single-molecule Förster resonance energy transfer (FRET) imaging at micromolar concentrations of an analyte is demonstrated. A quantum dot (QD)–dye donor–acceptor pair permits the approach of physiological levels of fluorescently labeled analytes when imaging molecular dynamics. Single-molecule FRET imaging of myosin ATP hydrolysis is performed using QDs attached to myosin as a donor enzyme and Cy3-labeled ATP as an acceptor ligand at micromolar levels (see image).

Single enveloped viruses can be prepared on a large scale with high efficiency by a layer-by-layer method. The virus/polyelectrolyte core/shell nanoparticles (VCSPs) exhibit unique characteristics, such as direct observation by electron microscopy without staining, easy separation and concentration, rapid perinuclear delivery, and improved biological safety, which resolve the conventional shortcomings of viruses in nanoscale applications.

A small quantity of stiff microstructures in a 3D matrix regulates human mesenchymal stem cells to increase proliferation and slow differentiation after 10 days in culture. Cell morphology, clustering, and gene expression (see image) are significantly different although the stiff microstructures are only 0.07% of the total gel volume.

Artificial single nanochannels with chemical/structural asymmetry and controllable continuous change of ionic-current rectification are prepared by ion-sputtering technology. The nanochannel is embedded in a track-etched poly(ethylene terephthalate) (PET) membrane and sputtered with Pt on the tip side of the nanochannel.

Chemical synthesis, stability, and characterization of a new albumin-based magnetic nanocarrier containing cobalt ferrite nanoparticles is reported. The BSA–cobalt-based nanocarrier is tested as a theranostic nanomedicine: both diagnostic abilities in vivo and therapeutic hyperthermic effects on standard human tumor cell line (HeLa cells, see image) are investigated.

The simple production of micro/nanoscale patterns with very high aspect ratios exceeding that of the mold used is demonstrated using unconventional top-surface lithography. The method combines inkless contact printing and subsequent dry pattern development by oxygen reactive ion etching (see image), making it possible to form high-resolution, high-aspect-ratio patterns without the aid of expensive optical protocols.

A one-dimensional heterostructure comprising single-walled carbon nanotubes (CNTs) and CdSe nanowires is prepared via electrochemical deposition of Bi nanoparticles onto the nanotubes (see image), followed by solution–liquid–solid synthesis of the semiconductor nanowires.

Copper nanotubes (NTs) and nanowires (NWs) with Y- and step-shaped topologies (see image) are built via electrodeposition inside anodic aluminum oxide templates. Thermal-expansion measurements demonstrate that their thermal-expansion coefficients (TECs) are temperature dependent and that the TECs of the stem/large-diameter segments are more sensitive than those of the branch/small-diameter segments.

The emitted relaxation energy of an organic–inorganic nanohybrid upon repeated heating/cooling cycles exhibits a logarithmic time dependence (associated with hierarchically constrained dynamics), thereby providing a conspicuous fingerprint of emergent complex behavior. It is proposed that the emergence of complexity may be the rule, rather than the exception, concerning the interplay of individual and collective behavior.

A supramolecular hydrogen-bonded network adsorbed on Au(111) can corral thiol self-assembled monolayers (SAMs) inside its pores. Enhancing the thermodynamic stability of these SAM nanoislands by Cu underpotential deposition allows selective replacement of the network by a second thiol species. The resulting binary SAM (see image) retains the periodicity and symmetry of the original supramolecular mask.

Nanocrystal formation of the bacterial protein SbpA on silicon dioxide and silane coupling agents is studied with high-resolution atomic force microscopy and quartz crystal microbalance with dissipation. S-layer formation occurs in three steps: protein adsorption, protein self-assembly, and crystalline-domain reorganization (see image). Substrate chemistry influences crystalline-domain size and layer compliance but not the crystal lattice parameters.

Simultaneous control over the anisotropy, shape, and size of poly(lactide-co-glycolide) (PLGA) microparticles via electrohydrodynamic co-jetting is demonstrated by the fabrication of bicompartmental discoid and rod-shaped particles in addition to spheres (see image). This is achieved by controlling different solution and process parameters during co-jetting. Such designer particles can be employed as novel therapeutic agents for drug delivery and diagnostics.

A multifunctional SiO2-based nanostructure is synthesized by a novel method. Preformed CdSe quantum dots and magnetite nanoparticles are incorporated within the channels of SiO₂ nanotubes (see image). The resulting nanostructure possesses intriguing photoluminescent and superparamagnetic properties characteristic of its constituent components.

The superiority of deposited conducting-polymer nanotubes of poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(pyrrole) (PPy) on neural microelectrodes (see image) compared to their film counterparts is reported in terms of resistance to delamination, reduced impedance, increased charge-capacity density, neural attachment, and neurite outgrowth.

Fluorescent nanocarriers that mimic high-density lipoprotein can target epidermal growth factor receptor (EGFR)-expressing cancer cells (see picture). The nanocarriers have controllable size, cargo loading, and shielding properties. The small size and surface properties result in excellent tumor accumulation, the modular targeting of the nanoparticle being essential for tumor cell uptake.

Nanomechanical peeling of thin free-standing bundles of single-walled carbon nanotubes is performed by in situ nanomanipulation techniques (see image) inside a high-resolution scanning electron microscope. The adhesion strength between bundled nanotubes at various peel-front positions is determined from the deformation curvatures of the delaminated nanotube bundle based on a nonlinear-elastica model.

Plasmon coupling through chains of Ag nanoparticles is investigated using electron energy-loss spectroscopy. In-phase and anti-phase coupling modes are identified in dimers by anisotropic plasmon mapping. The in-phase mode is found to be optically active and the path of light transportation is visualized.

The utility of actin bundles for nanotransport applications is examined. Actin bundling affects the translational behavior of the actin filaments and may be useful for the transport of molecular cargo (streptavidin-functionalized beads) while the myosin motor may be regulated photonically. These data suggest that actin bundling may significantly improve the applicability of the myosin motor for future nanotechnological applications.

Graphene thin films are prepared using surfactant-stabilized dispersions of graphene in water. Electromechanical stability coupled with high transparency make these films attractive as transparent flexible conductors (see image).

Microcontact printing is used to create a Janus self-assembled monolayer on both gold and titanium oxide surfaces (see image). The newly formed surfaces are subjected to surface reactions and, as an example application, are used for the chemisorption of bovine serum albumin. At each stage, the JSAMs are characterized by X-ray photoelectron spectroscopy and dynamic water-contact-angle measurements.

Hollow mesoporous spheres of Fe₃O₄@SiO₂ exhibit relatively fast cell uptake and no cytotoxicity up to a concentration of 150 µg mL⁻¹ after 48 h of incubation. Doxorubicin hydrochloride (DOX)-loaded spheres exhibit a somewhat higher cytotoxicity than free DOX (see picture). The Fe₃O₄SiO₂ spheres have potential for drug loading and delivery into cancer cells to induce cell death.