The use of hydrogen as an energy carrier to replace gasoline to fuel cars is widely discussed (see image). To achieve this goal, safe and high-capacity hydrogen-storage materials are needed. This Review article summarizes progress towards development of nanoporous materials based on organic polymers such as hypercrosslinked polymers, polymers of intrinsic microporosity, and covalent organic frameworks suitable to store hydrogen.

High-aspect-ratio II–VI semiconductor nanowires (NWs; see image) are prepared using solution–liquid–solid growth employing simple Bi salts. NW size control is achieved by varying the Bi content of the preparation, leading to wire diameters between 5 and 11 nm. Corresponding size-dependent trends are seen in the linear absorption/band-edge emission of the wires, suggesting carrier confinement.

Soft-processed organic transistors that exceed in performance compared to their counterparts made via standard microfabrication are demonstrated. The image shows the detail of an optical picture of the P3HT–Pt interface of an additively soft-patterned transistor, with Pt electrodes defined by MIMIC and P3HT stripes obtained by LCW.

The octahedral [Re₆Se₈(CN)₆]⁴⁻ ions with various bridging metal ions form well-defined cubic and hexagonal mesostructures (see image) in the presence of liquid-crystal template in formamide. The interaction between the positively charged micellar head groups of the template and the [Re₆Se₈(CN)₆]⁴⁻ ions is a pure noncovalent electrostatic interaction. These materials are coordination polymers with exceptionally large 1D or 3D potential pores because of the dimension of mesoscale liquid-crystal template.

A transmission electron microscopy (TEM) image shows the significant uptake of C₇₀ particles by a plant leaf cell. The C₇₀ particles appear as numerous small aggregates in the vacuole and the cell walls of the leaf cell are shown as dark layered structures in the image. Scale of image: 5 × 6 µm.

Large-area micropatterns of poly(acrylic acid) (PAA) nanodomains favorable for biological cell attachment are produced in a nonfouling poly(ethylene oxide) (PEO) matrix (see image). Nanoimprint-assisted microcontact stripping techniques are used to micropattern polystyrene nanobeads deposited on PAA. Subsequent etching of the nanobeads, followed by deposition of PEO by plasma-enhanced chemical vapor deposition, produces the fouling/non-fouling surface.

Enzyme-filled stable polymeric capsules (polymersomes) that are permeable to low-molecular-weight (pro-fluorescent) substrates can be sorted based on the activity of encapsulated enzymes using flow cytometry (see image). Enzymatic activity is screened by the build-up of fluorescent product that is prevented from leaking out by co-encapsulation of a trapping agent.

A laser fabrication technique for metal nanostructures is developed. Owing to the control of the growth of metal particles by surfactants, the spatial resolution of the technique breaks the classical limitation of the light. Three-dimensional silver nanostructures are experimentally demonstrated (see image).

Microdroplets are naturally well-defined reactors for performing reactions on the microscale. An innovative technique is presented to achieve one-step compound droplet formation in a microfluidic-channel structure. The image shows a droplet in the formation process and a droplet flowing downstream of the channel with mixing/reaction occurring inside it. Red and green colors denote different regents.

Uniform 100-nm megranate-like FeCo/gelatin nanospheres are self-assembled through the efficient chelation of small primary FeCo NCs with gelatin polypeptide chains in a one-pot reaction (see image). The unique nanospheres efficiently combine rapid magnetic response, huge active surface, and high capacity of controlled loading and releasing of DNA molecules.

Cube roots: Chemiresistors based on cubic monolayer-capped nanoparticles (MCNPs) produce a higher electrical response upon exposure to volatile organic compounds than those based on spherical MCNPs. These observations are explained in terms of the higher swellability of cubic MCNPs compared to spherical MCNPs (see picture).

The fabrication of graphitic carbon nanostructures using electron beam lithography followed by high- temperature pyrolysis is demonstrated. The procedure produces conductive structures of a variety of shapes and sizes (see image). It is shown that carbon nanowires with a predefined conductance can be fabricated. The application of these structures as nanoband electrodes is also demonstrated.

Photocontrollable DNA Nanodevices: Using structurally addressable DNA as a scaffold, an optically addressable nanodevice with the photoconvertible protein Dronpa and Atto647N is fabricated (see image). The device is characterized using single-molecule spectroscopy. As nanodevices are well suited for the investigation of cellular processes, the ability to optically detect and address this nanodevice in the context of a living cell is shown.

The treatment of a human lung carcinoma model in vivo using siRNA sequences leading to cytotoxicity and cell death is carried out. Carbon-nanotube-mediated delivery of siRNA by intratumoral administration leads to successful suppression of tumor volume, and prolonged survival of human lung tumor-bearing animals (see image).

A microfluidic device containing a double-grooved substrate for cell docking and positioning is presented. Numerical simulations of microcirculations within double grooves (see image) elucidate the dependence of the flow pattern on groove geometry. Cell docking and retention are measured experimentally for double grooves of two aspect ratios and three depth ratios, and correlate directly to the microcirculation pattern.

Although electrospun nanofiber meshes (see image) have morphological similarities with natural extracellular matrixes, surface roughness and chemistry are still key parameters for enhanced cellular performance. This work shows that three different cell types (osteoblasts, fibroblasts, and chondrocytes) prefer specific plasma surface modifications, suggesting that the surface chemistry also has a key role in the biological performance of nanostructured surfaces.

In vitro derby imaging of RGD peptide targeting integrin α_vβ₃ protein (green in image) and AS1411 aptamer targeting nucleolin protein (red) using two different quantum dots (605 and 655 nm) is successfully visualized in HeLa cells, simultaneously. Fluorescent imaging signatures of the overlay (yellow) from the integrin α_vβ₃ and nucleolin show the co-localization in the cellular membrane.

3D-cell-culture-based nanoparticle toxicity testing shows significantly reduced toxic effects compared to the conventional cytotoxicity testing in 2D cell culture (see image). Tissue-like morphology and phenotypic change are the major factors in diminishing toxicity by limiting cellular interaction and diffusion of nanoparticle-induced toxicants.