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The cover picture features the self-assembly of anisotropic colloidal particles, which can improve the fundamental understanding of crystallization and the glass transition as well as be applied for materials with advanced optical and mechanical properties. A DC electric field device is used to rapidly self-assemble spheroids. The main image depicts a suspension of colloidal spheroids subject to a DC electric field, which leads to the formation of a crystalline phase. The confocal microscopy (CLSM) image of one such structure is shown between the electrodes, and the upper left corner shows a 3D rendering of the assembly, as generated by image processing of CLSM results. The electric field device is overlaid on a scanning electron microscopy image of the disordered spheroids, and the background image is a larger-scale confocal microscopy image of an electric-field-induced assembly. For further information, please read the Full Paper “Liquid Crystal Order in Colloidal Suspensions of Spheroidal Particles” by M. J. Solomon and co-workers beginning on page 1551. Image credit: Benjamin Schultz, Mahesh Ganesan, and Aayush A. Shah.

The cover image features a highly efficient nanolithography technique with a minimal number of processing steps, integrating directed block-copolymer self-assembly with single-step ZnO nanoimprinting. Diverse shapes of the ZnO patterns are readily attainable by UV-assisted, single-step imprinting of sol–gel precursors. The ZnO provides high thermal stability and low line-edge roughness, both of which are crucial for further directed blockcopolymer assembly. According to the ZnO trench shape, various self-assembled nanoscale morphologies—such as surface-parallel nanocylinder arrays, hierarchical nanopatterns of surface-parallel and vertical cylinder arrays, and co-axial nano-ring arrays—can be formed in the graphoepitaxially assembled block-copolymer thin films. For more information, please read the Full Paper “Graphoepitaxy of Block-Copolymer Self-Assembly Integrated with Single-Step ZnO Nanoimprinting” by S. O. Kim, J.-H. Jeong, and co-workers, beginning on page 1563.

A detailed review of the experimental approaches followed for the structuration of magnetic nanoparticles on surfaces is presented. Special attention is given to understand the parameters that control self-assembly, including the use of biological templates. Finally, the implementation of all the knowledge previously gained is translated to the integration and implementation on sensors and devices.

A bimodular genetic fusion comprising a delivery module (scFv) and a capture module (SNAP) is proposed as a novel strategy for the site-specific covalent conjugation of targeting peptides to nanoparticles. An scFv mutant selective for HER2 tumor antigen is chosen as the targeting ligand. SNAP-scFv is immobilized on magnetofluorescent nanoparticles and its targeting efficiency against HER2-positive cells is assessed by flow cytometry and immunofluorescence.

Hybrid magnetic phospholipidic-based tubular and helical microagents are wirelessly manipulated by means of a 5-DOF electromagnetic system. Two different strategies are used to manipulate these nanostructures in simulated biologic capillaries. Tubules are pulled by applying magnetic field gradients and oriented by magnetic fields. Helices exhibit a cork-screw motion similar to the swimming strategy used by motile bacteria such as E. coli.

A fano resonance is observed in highly symmetric nanostructures comprising Au nanosphere cores and dielectric shells. It arises from the interference between the narrow plasmon resonance of the Au nanosphere core and the broad scattering background of the dielectric shell. The Fano resonance behavior is dependent on the gap distance between the core and shell and the shell material.

Nanofibers are synthesized by electrospinning highly loaded water-based precursor–polymer hybrid solutions followed by thermal treatment to control crystal structure. Electrical conductivity and magnetic coercivity, as shown, are tested displaying independent magnetic and electrical property control from coercive to superparamagnetic and resistive to near-bulk conductivity at room temperature.

High-quality cobalt-doped ceria nanostructures with triangular column, triangular slab, and disklike shapes are synthesized by tuning the doping amount of cobalt nitrate in a facile hydrothermal reaction. The cobalt-doped ceria nanodisks display significantly enhanced catalytic activity in CO oxidation due to exposed highly active crystal planes and the presence of numerous surface defects.

In-plane nanofluidic channels with 3D topography are fabricated. Nanochannel masters are written by electron beam lithography in SU-8 resist and shaped by electron-beam-induced etching (EBIE) with water as the precursor gas. Nanofunnel replicas cast from unmodified and EBIE-modified masters show that the funnel tip dimensions decrease from a 150-nm depth and 80-nm width to a 70-nm depth and 40-nm width.

Single-crystalline Au_xAg_1–x nanowires (NWs) are synthesized by a topotaxial method using Ag vapor transport. Au_0.5Ag_0.5 NWs are more inert than Ag NWs to oxidation and have significant plasmonic activity in the blue wavelength region. They have strong surface- enhanced Raman scattering enhancement comparable to that of Ag NWs. The characteristics of Au_0.5Ag_0.5 NWs make them candidates for improved plasmonic devices.

A pulsed CVD approach is demonstrated to grow short arrays of continuous single-wall carbon nanotubes (SWNTs) in increments as small as 25 nm. The fast nucleation and growth kinetics and array height are measured in real-time within each subsecond gas pulse by time-resolved laser reflectivity.

A mitochondria-targeting photoacoustic modality using unmodified single-walled carbon nanotubes (SWNTs) and pulse laser irradiation suppresses tumor growth by selectively destroying tumor tissue without causing epidermis injury, due to the higher mitochondrial transmembrane potential in cancerous cells than normal cells. A new photoacoustic method for cancer treatment is provided.

Rapid assembly of anisotropic colloidal particles is essential to create complex, uniform, and scalable crystal structures for applications. In this study, DC electric fields are used to accelerate the self-assembly process of spheroidal particles. The image shows confocal microscopy images and renderings from image processing of the field-induced 3D ordering. The assembly is shown to have high-quality orientational order and previously unobserved periodic and dense layered ordering.

ZnO topographic patterns with various pattern shapes formed by a single-step nanoimprinting process can serve as templates for graphoepitaxial block-copolymer assembly, generating complex hierarchical nanopatterns where surface-parallel and surface-perpendicular nanocylinder arrays are alternately arranged.

A versatile device for the creation of grayscale protein patterns by photobleaching in a reproducible manner is developed. Filtered, collimated light is projected onto a digital mirror device, which is set according to a digital grayscale image. This image is demagnified and projected onto a substrate for the creation of protein patterns.

Whole animal magnetic resonance imaging (MRI) and fluorescence analyses demonstrate that poly(glycidyl methacrylate) (PGMA) nanoparticles coated with polyethylenimine (PEI) and containing an MRI contrast agent (superparamagnetic iron oxide nanoparticles) and fluorophore (rhodamine B), remain close to the site of injection into a partial injury of the optic nerve, which is a central nervous system white matter tract.

Membrane tubulation protein amphiphysin induces the assembly of 1D tubulated liposomes with functional nanoparticles, such as quantum dots, embedded within the lipid bilayer under ambient conditions. The functional lipid tubule is developed within 15 min at 37 °C, and shows high aspect ratio and stability for more than 20 h.

A novel amphiphilic biodegradable poly(aspartic acid (AA)-co-lactic acid (LA))/DPPE co-polymer is synthesized and used to prepare doxorubicin (DOX)-loaded nanoparticles for tumor therapy. These nanoparticles are prepared by double emulsion method and exhibit pH-responsive drug release profiles. It is of great interest that these poly(AA-co-LA)/DPPE nanoparticles can efficiently deliver a chemotherapy drug DOX into the nuclei specifically within tumor cells and show dose- and time-dependent cytotoxicity.

The effect of hydrogenation of graphene and graphite surfaces is studied by scanning tunneling microscopy and spectroscopy. An Ar/H₂ plasma is used to chemically modify the surface of the samples, opening an energy bandgap of 0.4 eV. Moderate annealing is enough to close this bandgap and the samples can be hydrogenated again to yield a similar semiconducting behavior.

A novel printing method for highly aligned nanowires that are self-assembled at pre-defined microstructures using hydrodynamic flow of solvent and entropic force fields is demonstrated. Si nanowires are successfully aligned and printed onto flexible substrate with high density and aligning accuracy without any additional treatments using direct gravure printing.