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The cover picture shows nanocoral probes docking on a cancer-cell membrane (combination of false-color scanning electron micrograph and illustration). Nanocorals are a new class of bioinspired nanoprobes, which demonstrate independent cell-targeting and label-free biomolecular sensing capabilities. The highly roughened gold region of the nanocoral increases the molecular adsorption capacity and causes a strong surface-enhanced Raman spectroscopy signal. The smooth polystyrene region can adsorb antibodies, allowing the nanocoral to specifically bind to receptors on the cancer-cell membrane, making nanocorals multifunctional nanosensors for cellular diagnostics and treatment evaluation. For more information, please read the Communication “Bioinspired Nanocorals with Decoupled Cellular Targeting and Sensing Functionality” by L. P. Lee et al., beginning on page 503.

The cover picture shows a microfluidic channel between two reservoirs made of SiN on a SiO₂ substrate. In the channel lies several microelectrodes made of platinum. ZnO nanowires are grown from nanoparticles deposited on the electrodes using AC dielectrophoresis. The device shows n-type transport characteristics with 4 to 6 orders of magnitude modulation of conductance. ZnO nanowires are thereafter functionalized with 3-aminopropyltriethoxysilane to be used as pH sensors. For more information, please read the Full Paper “Site-Specific Self-Assembled Liquid-Gated ZnO Nanowire Transistors for Sensing Applications” by K. Balasubramanian et al., beginning on page 589.

Micro- and nanoarchitectural design of biomaterial structures is essential to reach the full potential of the biomaterials' chemical and biological properties. A useful strategy to fabricate biomaterials with unique and novel architectures is through the use of templates that have defined geometrical features.

Silicon-based chips offer high flexibility and versatility as they are based on semiconductor and MEMS technology. They can be top-down fabricated with well-controlled shape and size. Silicon microchips can be internalized into eukaryotic cells (see image) without interfering with cell viability. Engineered intracellular chips with different biomolecules attached to the surface can be used as intracellular sensors.

Nanocorals demonstrate independent cell-targeting and label-free biomolecular sensing capabilities. The highly roughened gold region of the nanocoral increases the adsorption capacity and causes a strong surface-enhanced Raman spectroscopy (SERS) signal. The polystyrene region can adsorb antibodies, allowing the nanocoral to specifically bind to receptors on the cancer cell membrane making nanocorals multifunctional nanosensors for cellular diagnostics and treatment evaluation.

The phase-separated structure of blends of the ferroelectric polymer P(VDF-TrFE) and the semiconducting polymer P3HT used in organic non-volatile memories is revealed with soft X-ray spectromicroscopy. These thin-film blends show a columnar morphology, with P3HT-rich columns enclosed in a continuous, essentially pure P(VDF-TrFE) phase favorable for data storage operation.

A novel photochemical method for the synthesis of fluorescent Au nanodots (size ≈1.2nm) is proposed (see image). The results clearly demonstrate that reduced graphene oxide sheets modified with functional organic molecules can be used as templates for the synthesis and in situ assembly of metal nanostructures, thus opening up new possibilities for future graphene-based chemical synthesis.

The size, shape, and surface chemistry of a gold nanostructure can influence its adsorption and internalization by a cell (see image). This work compares gold nanostructures of two different sizes, two different shapes, and three different surface functional groups.

A simple kinetic control strategy is used to tune the crystal structure of Au nanoparticles in a modified polyol synthesis. Single-crystalline nanoparticles, decahedral MTPs, and icosahedral MTPs with uniform crystal structure and narrow size distribution are obtained by only varying the HAuCl₄ concentration.

The compressive strength of nanosized-crystal metallic pillars is known to depend on their diameter. The role of pillar height is examined, and the suppression of generalized crystal plasticity is observed below a critical value. In situ compression tests on regular pillars and nanobuttons show the latter to be much harder, withstanding stresses >2GPa.

Nanoscale graphene oxide (NGO) with good biocompatibility and physiological stability is synthesized by functionalization with sulfonic acid groups and conjugation with folic acid. In the delivery of multiple drugs, cellular-uptake experiments show the targeted delivery of the anticancer drugs doxorubicin and camptothecin into cells (see picture) by the NGO via receptor-mediated endocytosis.

Negatively charged, hydrophobic gold and silver nanoparticles coated with cationic dodecylamine accumulate at the gas/water cavitation interface formed by ultrasound, and penetrate the gas-phase interior of microbubbles. The temperature inside the hot-spot microenvironment is high enough to melt the metallic nanoparticles and form binary Au/Ag-alloy nanostructures.

The frontispiece shows molecular models of semiconductor quantum dots functionalized with surface solubilizing ligands, a <20 residue peptide, myoglobin, mCherry, and a maltose binding protein that together cover a range of masses from <2.2 to ≈44 kDa. The corresponding study reports on determining the number of proteins or peptides that can be attached to semiconductor quantum-dot nanocrystals. This problem has intrigued materials scientists for years and is an important component of designing such bioconjugates. For more information, please read the Full Paper “Polyvalent Display and Packing of Peptides and Proteins on Semiconductor Quantum Dots: Predicted Versus Experimental Results” by I. L. Medintz et al., beginning on page 555.

Quantum dots (QDs) are loaded with a series of peptides and proteins of increasing size including a <20 residue peptide, myoglobin, mCherry, and maltose binding protein, which cover a range of masses from <2.2 to ≈44 kD. These data provide insight into the QD surface, binding capacity, and the role played by the nanoparticle's surface solubilizing ligands.

Catalytic silica–platinum sphere-dimer nanomotors in solution and nanorotors at the solid solution interface propelled by the decomposition of aqueous hydrogen peroxide on the platinum are probed experimentally and their motion is simulated theoretically for different dimensions of the platinum sphere component. The nature of the interaction between sphere dimer and substrate is analyzed and discussed.

Thermally stable, near-monodisperse Bi nanoparticles are synthesized from BiCl₃ and Na[N(SiMe₃)₂] in a one-step reaction, which avoids the preparation and use of Bi[N(SiMe₃)₂]₃. Diameter control in the range of 4–29 nm is achieved by varying the molar ratio of the reagents. The Bi nanoparticles catalyze the solution–liquid–solid (SLS) growth of diameter-controlled high-quality CdSe quantum wires.

Quantum yields related to photo-emissions originating from the photoexcitation of MgO nanocube corners and edges are measured (see image). In addition, these particles are utilized as a support for significantly smaller BaO clusters, which enhances the photoemission quantum yields by orders of magnitude.

A scalable bottom-up solution-based approach is reported for the site-specific realization of ZnO nanowire (ZnO-NW)-based field-effect transistors for sensing applications in liquids. Using integrated on-chip microchannels and microfabricated gate electrodes, electrochemically gated ZnO-NW transistors functioning in liquids (see image) are demonstrated. The combination of sensitivity, site specificity, and cost effectiveness shows promise for routine analytical and diagnostic applications.