Magnetoplasmonic gold nanorods for the sensitive and label-free detection of glutathione.

This work exploits the magneto-optical activity of gold nanorods for the detection of sub-micromolar concentrations of glutathione using magnetic circular dichroism spectroscopy. Modulations of the magnetoplasmonic response of nanorods serve as the basis of the sensing methodology, whereby the presence of glutathione induces the end-to-end assembly of nanorods. In particular, the nanorod self-assembly enables a localized electric field in the nanocavities with adsorbed thiol molecules, whose field strength is amplified by the external magnetic field as confirmed by finite-element modeling, enabling their high-sensitivity detection.

Versatile fabrication of metal sulfide supraparticles by an decomposition-assembly strategy.

Supraparticles (SPs) are of great importance in both fundamental and applied studies due to their emerging collective properties, synergistic effects, and various applications. Metal sulfide nanomaterials are of vital importance in biomedicine, catalysis, battery materials, and other fields. Herein, an decomposition-assembly strategy for the versatile fabrication of metal sulfide SPs is developed.

Conformational evolution following the sequential molecular dehydrogenation of PMDI on a Cu(111) surface.

Molecular spatial conformational evolution following the corresponding chemical reaction pathway at surfaces is important to understand and optimize chemical processes. Combining experimental and theoretical methods, the sequential N-H and C-H dehydrogenation of pyromellitic diimide (PMDI) on a Cu(111) surface are reported. STM experiments and atomistic modeling allow structural analysis at each well-defined reaction step.

Inhibition of cardiomyocyte apoptosis post-acute myocardial infarction through the efficient delivery of microRNA-24 by silica nanoparticles.

MicroRNA-24 (miR-24) is an apoptosis suppressor miRNA downregulated in cardiomyocytes after acute myocardial infarction (AMI). However, due to the lack of effective delivery strategies, the role of anti-apoptotic miR-24 in cardiomyocytes post-acute myocardial infarction remains unexplored. Here, we used a silica nanoparticle-based polyelectrolyte (polyethylenimine, PEI) delivery system to study the role of miR-24.

Low-fouling CNT-PEG-hydrogel coated quartz crystal microbalance sensor for saliva glucose detection.

Saliva glucose detection based on a quartz crystal microbalance (QCM) sensor has emerged as a promising tool and a non-invasive diagnostic technique for diabetes. However, the low glucose concentration and strong protein interference in the saliva hinder the QCM sensors from practical applications. In this study, we present a robust and simple anti-fouling CNT-PEG-hydrogel film-coated QCM sensor for the detection of saliva glucose with high sensitivity.

Enhanced negative magnetoresistance near the charge neutral point in Cr doped topological insulator.

Negative magnetoresistance (MR) is not only of great fundamental interest for condensed matter physics and materials science, but also important for practical applications, especially magnetic data storage and sensors. However, the microscopic origin of negative MR is still elusive and the nature of the negative MR in magnetic topological insulators has still not been completely elucidated. Here, we report magnetotransport studies on Cr doped (Bi Sb )Te topological insulator thin films grown by magnetron sputtering.

A reconstructed porous copper surface promotes selectivity and efficiency toward C products by electrocatalytic CO reduction.

Electrocatalytic synthesis of multicarbon (C) products from CO reduction suffers from poor selectivity and low energy efficiency. Herein, a facile oxidation-reduction cycling method is adopted to reconstruct the Cu electrode surface with the help of halide anions. The surface composed of entangled Cu nanowires with hierarchical pores is synthesized in the presence of I, exhibiting a C faradaic efficiency (FE) of 80% at -1.

Optimizing Surface Chemistry of PbS Colloidal Quantum Dot for Highly Efficient and Stable Solar Cells via Chemical Binding.

The surface chemistry of colloidal quantum dots (CQD) play a crucial role in fabricating highly efficient and stable solar cells. However, as-synthesized PbS CQDs are significantly off-stoichiometric and contain inhomogeneously distributed S and Pb atoms at the surface, which results in undercharged Pb atoms, dangling bonds of S atoms and uncapped sites, thus causing surface trap states. Moreover, conventional ligand exchange processes cannot efficiently eliminate these undesired atom configurations and defect sites.

Rubidium Ions Enhanced Crystallinity for Ruddlesden-Popper Perovskites.

Tailoring the organic spacing cations enables developing new Ruddlesden-Popper (RP) perovskites with tunable optoelectronic properties and superior stabilities. However, the formation of highly crystallized RP perovskites can be hindered when the structure of organic cations become complex. Strategies to regulate crystal growing process and grains quality remain to be explored.

Cobalt/nitrogen codoped carbon nanosheets derived from catkins as a high performance non-noble metal electrocatalyst for oxygen reduction reaction and hydrogen evolution reaction.

Novel energy devices which are capable of alleviating and/or solving the energy dilemma such as overall water splitting and fuel cells require the development of highly efficient catalysts, especially cheap high performance non-precious metal (NPM) catalysts. Here, we prepare highly efficient NPM catalysts of cobalt and nitrogen codoped carbon nanosheets (Co/N-CNSs) for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) using harmful environment-polluting waste of biomass catkins as carbon precursors a mild mechanical exfoliation and chemical process which is facile, low-cost, environmentally friendly and up-scalable. Compared with a commercial platinum-based catalyst (commercial 20% Pt/C), the Co/N-CNS electrocatalysts show outstanding ORR activity, acceptable HER activity and long term stability with an onset potential of 0.

Shape-dependent close-edge 2D-MoS nanobelts.

Atomic-thin MoS materials have attracted increasing attention due to their potentials in numerous fields. However, in 2D-MoS sheets, the edge region usually has unique features differing from the interior region, which has potential application in enhancing catalysts and shape-dependent 2D-nanodevices. However, fabricating it cost-effectively is still very difficult.

Unveiling the Effects of Hydrolysis-Derived DMAI/DMAPbI Intermediate Compound on the Performance of CsPbI Solar Cells.

Introducing hydroiodic acid (HI) as a hydrolysis-derived precursor of the intermediate compounds has become an increasingly important issue for fabricating high quality and stable CsPbI perovskite solar cells (PSCs). However, the materials composition of the intermediate compounds and their effects on the device performance remain unclear. Here, a series of high-quality intermediate compounds are prepared and it is shown that they consist of DMAI/DMAPbI .

Small molecule-decorated gold nanoparticles for preparing antibiofilm fabrics.

The increase in antibiotic resistance reported worldwide poses an immediate threat to human health and highlights the need to find novel approaches to inhibit bacterial growth. In this study, we present a series of gold nanoparticles (Au NPs) capped by different N-heterocyclic molecules (N_Au NPs) which can serve as broad-spectrum antibacterial agents. Neither the Au NPs nor N-heterocyclic molecules were toxic to mammalian cells.

Ag@BiOCl super-hydrophobic nanostructure for enhancing SERS detection sensitivity.

Surface-enhanced Raman scattering (SERS) has received widespread attention in the rapid detection of trace substances. The super-hydrophobic surface of structures has a significant impact on improving SERS performance. Usually a low concentration of objective molecules is randomly distributed in a large area on a non-hydrophobic SERS substrate, resulting in the Raman signals of the molecules not being easily detected.

The effect of size and surface ligands of iron oxide nanoparticles on blood compatibility.

Superparamagnetic iron oxide nanoparticles (SPIONs) have been widely used and have attracted increased attention for their unique physicochemical properties, especially in biomedical sciences as contrast agents following intravenous administration. However, only few studies have systematically reported the blood compatibility of iron oxide nanoparticles with different physicochemical properties such as different sizes and surface ligands. Therefore, we selected three widely used organic ligands (polyacrylic acid, hyaluronic acid, and chitosan) with modified SPIONs at the same size of 5-6 nm, and polyacrylic acid-modified SPIONs with different sizes (5, 10, and 30 nm) at different concentrations to evaluate their haemocompatibility.

Surface chemistry of gold nanoparticles for health-related applications.

Functionalization of gold nanoparticles is crucial for the effective utilization of these materials in health-related applications. Health-related applications of gold nanoparticles rely on the physical and chemical reactions between molecules and gold nanoparticles. Surface chemistry can precisely control and tailor the surface properties of gold nanoparticles to meet the needs of applications.

Self-Supply of O and HO by a Nanocatalytic Medicine to Enhance Combined Chemo/Chemodynamic Therapy.

Combined chemo/chemodynamic therapy is a promising strategy to achieve an improved anticancer effect. However, the hypoxic microenvironment and limited amount of HO in most solid tumors severely restrict the efficacy of this treatment. Herein, the construction of a nanocatalytic medicine, CaO@DOX@ZIF-67, via a bottom-up approach is described.

Peptide conformation and oligomerization characteristics of surface-mediated assemblies revealed by molecular dynamics simulations and scanning tunneling microscopy.

The characteristics of peptide conformations in both solution and surface-bound states, using poly-glycine as a model structure, are analyzed by using molecular dynamics (MD) simulations. The clustering analysis revealed significant linearization effect on the peptide conformations as a result of adsorption to surface, accompanied by varied adsorption kinetics and energetics. Depending on the inter-peptide interaction characteristics, distinctively different surface-mediated oligomerization modalities, such as antiparallel conformations, can be identified in MD and confirmed by scanning tunneling microscopy (STM) analysis of the assembly structures.

Isothermal kinase-triggered supramolecular assemblies as drug sensitizers.

Protein kinases, the main regulators of a vast map of cellular processes, are the most attractive targets in drug discovery. Despite a few successful examples of protein kinase inhibitors, the drug discovery strategy of downregulating protein kinase activity has been quite limited and often fails even in animal models. Here, we utilize protein kinase A (PKA) activity to design PKA-triggered supramolecular assemblies with anticancer activities.

A Generalized Methodology of Designing 3D SERS Probes with Superior Detection Limit and Uniformity by Maximizing Multiple Coupling Effects.

Accurate design of high-performance 3D surface-enhanced Raman scattering (SERS) probes is the desired target, which is possibly implemented with a prerequisite of quantifying formidable multiple coupling effects involved. Herein, by combining theory and experiments on 3D periodic Au/SiO nanogrid models, a generalized methodology of accurately designing high performance 3D SERS probes is developed. Structural symmetry, dimensions, Au roughness, and polarization are successfully correlated quantitatively to intrinsic localized electromagnetic field (EMF) enhancements by calculating surface plasmon polariton (SPP), localized surface plasmon resonance (LSPR), optical standing wave effects, and their couplings theoretically, which is experimentally verified.

Controlling Injection Barriers for Ambipolar 2D Semiconductors via Quasi-van der Waals Contacts.

Barriers that charge carriers experience while injecting into channels play a crucial role on determining the device properties of van der Waals semiconductors (vdWS). Among various strategies to control these barriers, inserting a graphene layer underneath bulk metal may be a promising choice, which is still lacking experimental verification. Here, it is demonstrated that graphene/metal hybrid structures can form quasi-van der Waals contacts (q-vdWC) to ambipolar vdWS, combining the advantages of individual metal and graphene contacts together.

Correction: Improving the inhibitory effect of CXCR4 peptide antagonist in tumor metastasis with an acetylated PAMAM dendrimer.

[This corrects the article DOI: 10.1039/C8RA08526A.].

A ternary SnSSe alloy for flexible broadband photodetectors.

Layered two-dimensional (2D) materials often display unique functionalities for flexible 2D optoelectronic device applications involving natural flexibility and tunable bandgap by bandgap engineering. Composition manipulation by alloying of these 2D materials represents an effective way in fulfilling bandgap engineering, which is particularly true for SnS Se alloys showing a continuous bandgap modulation from 2.1 eV for SnS to 1.