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Poor interfacial contact between solid‐state electrolytes and electrodes limits high‐voltage performance of solid‐state lithium batteries. A new gel electrolyte is proposed via in‐situ polymerization, incorporating fluoroethylene carbonate (FEC) solvent and ionic liquid1‐butyl‐1‐methylpiperidinium bis(trifluoromethylsulfonyl)imide (PP14TFSI). This combination synergistically enhances Li ion transport, achieving a transfer number of 0.58 and improved electrochemical performance. FEC protects the Al current collectors from LiPF6 corrosion and promotes a protective interfacial layer formation. PP14TFSI improves interfacial contact and provides stable components. An interface layer of fluorine and nitrogen composites forms, preventing side reactions. LiCoO2||PPE||Li cell exhibits robust cycling stability at 4.45 V, retaining ~80 % capacity after 200 cycles at room temperature with 0.2 C and 1 C rates, showing increased coulombic efficiency. NCM811||PPE||Li cell also displays exceptional cycling. In‐situ polymerization and FEC‐ionic liquid coordination enable high‐voltage solid‐state lithium metal batteries for practical use. [ABSTRACT FROM AUTHOR]

Curcumin (Cur) is an acidic polyphenol with some effects on α‐glucosidase (α‐Glu), but Cur has disadvantages such as being a weak target, lacking passing the blood–brain barrier and having low bioavailability. To enhance the curative effect of Cur, the hybrid composed of ZnO nanoparticles decorated on rGO was used to load Cur (ZnO@rGO‐Cur). The use of the multispectral method and enzyme inhibition kinetics analysis certify the inhibitory effect and interaction mechanism of ZnO@rGO‐Cur with α‐Glu. The static quenching of α‐Glu with both Cur and ZnO@rGO‐Cur is primarily driven by hydrogen bond and van der Waals interactions. The conformation‐changing ability by binding to the neighbouring phenolic hydroxyl group of Cur increased their ability to alter the secondary structure of α‐Glu, resulting in the inhibition of enzyme activity. The inhibition constant (Ki, Cur > Kis,ZnO@rGO‐Cur) showed that the inhibition effect of ZnO@rGO‐Cur on α‐Glu was larger than that of Cur. The CCK‐8 experiments proved that ZnO@rGO nanocomposites have good biocompatibility. These results suggest that the therapeutic potential of ZnO@rGO‐Cur composite is an emerging nanocarrier platform for drug delivery systems for the potential treatment of diabetes mellitus. [ABSTRACT FROM AUTHOR]

Herein, the visible light‐photocatalytic performance of synthesized ZnO/Gr composite materials with different Gr content under various conditions, i.e., pH, dye concentration, and different scavengers (to understand the photocatalytic activity mechanism) is systematically investigated. Photocatalytic performance is evaluated with the degradation of methylene blue (MB) in solution under sunlight irradiation. The presence of graphene (Gr) in the ZnO/Gr composites shows enhanced photocatalytic activity compared to pure ZnO under natural sunlight illumination. The highest photodegradation efficiency of ≈94% when the content of Gr is 1 wt% in comparison to ≈76% for the pure ZnO, corresponding to reaction rate constants of 0.01038 and 0.00615 min−1, respectively. Compared to recent publications, the degradation efficiency is high with relatively high dye concentration, low catalyst amount, and large solution volume. The enhanced visible light absorption and the reduction of bandgap value are attributed to the enhanced photocatalytic properties of the hybridized composite. Moreover, the investigation of the effect of scavenger substances shows that H2O2 strongly enhanced their photocatalytic ability, suggesting that holes (h+) contribute as the reactive agent in the photodegradation process. [ABSTRACT FROM AUTHOR]

Wearable sensors are currently one of the top emerging areas with enormous growth potential. Low‐cost fabrication techniques using simple and scalable printing technologies are making a significant impact on their development. Recent advances in high‐performance gas/vapor sensors based on carbon nanomaterials have shown potential applications ranging from disease diagnostics to environmental monitoring and defences. Herein, a hybrid sensing material of 1D carbon nanotubes (CNTs) and 2D graphene is developed, and a conductive ink is formulated, which is applied for fabricating a nitrogen dioxide (NO2) gas sensor array within a compact design utilizing extrusion printing. To improve NO2‐sensing performance and optimal operating temperature, a reverse‐side layer is designed, which combines MXene and poly(3,4‐ethylenedioxythiophene)‐doped poly(styrene sulfonate) (PEDOT:PSS), and functions as a Joule heater. The printed CNT–graphene‐based sensor with an embedded MXene/PEDOT:PSS heater is capable of detecting trace amounts of NO2 gas (1 ppm) at 65 °C. The sensor is able to distinguish between various gases/volatile organic compounds and target NO2 gas based on their chemical affinities. The printed CNT–graphene sensor array also demonstrates a high‐level of recoverability, satisfied stability, durability, and reproducibility, which render this sensor a suitable candidate for practical applications. [ABSTRACT FROM AUTHOR]

Neural tissue engineering aims to restore the function of nervous system tissues using biocompatible cell‐seeded scaffolds. Graphene‐based scaffolds combined with stem cells deserve special attention to enhance tissue regeneration in a controlled manner. However, it is believed that minor changes in scaffold biomaterial composition, internal porous structure, and physicochemical properties can impact cellular growth and adhesion. The current work aims to investigate in vitro biological effects of three‐dimensional (3D) graphene oxide (GO)/sodium alginate (GOSA) and reduced GOSA (RGOSA) scaffolds on dental pulp stem cells (DPSCs) in terms of cell viability and cytotoxicity. Herein, the effects of the 3D scaffolds, coating conditions, and serum supplementation on DPSCs functions are explored extensively. Biodegradation analysis revealed that the addition of GO enhanced the degradation rate of composite scaffolds. Compared to the 2D surface, the cell viability of 3D scaffolds was higher (p < 0.0001), highlighting the optimal initial cell adhesion to the scaffold surface and cell migration through pores. Moreover, the cytotoxicity study indicated that the incorporation of graphene supported higher DPSCs viability. It is also shown that when the mean pore size of the scaffold increases, DPSCs activity decreases. In terms of coating conditions, poly‐ l‐lysine was the most robust coating reagent that improved cell‐scaffold adherence and DPSCs metabolism activity. The cytotoxicity of GO‐based scaffolds showed that DPSCs can be seeded in serum‐free media without cytotoxic effects. This is critical for human translation as cellular transplants are typically serum‐free. These findings suggest that proposed 3D GO‐based scaffolds have favorable effects on the biological responses of DPSCs. [ABSTRACT FROM AUTHOR]

The coexistence of multiple toxic water pollutants (heavy metals, organic dyes, oils, and organic solvents) limits the sustainable supply of clean water worldwide and urges the development of advanced water purification technology that can remove these contaminants simultaneously. Since its discovery, graphene‐based materials have gained substantial attention toward development of new‐generation sorbents for water purification. Despite several recently published reviews on water purification technology using graphene and its derivatives, there is still a gap in the review considering multiple water‐pollutant remediation using advanced graphene materials. In this review, in the first instance, a comparative structure–function–performance relationship between graphene‐based sorbents and the multipollutants in water is established. A fundamental correlation is made between the sorption performance for diverse pollutants in water with the more specific adsorption properties (surface area, pore size, type of functional groups, C/O, C/N, and C/S atomic ratio) of advanced graphene sorbents. Second, the underlying interaction mechanisms are uncovered between different classes of water pollutants using single graphene‐based sorbents. Third, the rational design of advanced multipollutant sorbents based on graphene is elaborated. The reality, challenges, and opportunities of advanced graphene materials as emerging sorbents for sustainable water purification technology are finally presented in the last section. [ABSTRACT FROM AUTHOR]

Polluted waters are complex systems with many different co‐existing contaminants that make their simultaneous removal a very challenging task. To address this problem, all‐in‐one ad/ab‐sorbent with unique combination of interfacial properties and multiple surface chemistry is developed to simultaneously and efficiently remove several pollutants including heavy metals, dyes, oils, and organic solvents. By mimicking the wetting micro‐topology of a darkling beetle with a combined hydrophilic‐hydrophobic surface, a new bioinspired adsorbent, graphene biopolymer foam (Alg‐Fe3O4‐rGO‐4S) for removal of multiple water pollutants is engineered by combining alginate (Alg) and reduced graphene oxide (rGO) functionalized with tetrathiol that is also decorated with iron oxide nanoparticles (Fe3O4). This concept is first proved by single pollutant removal, showing adsorption capacity of 789.7 ± 36 mg/g for methylene blue (MB), 107.0 ± 2.1 mg/g for Hg (II), 73.5 ± 0.7 mg/g for Cu (II), and rapid oil‐water separation with high sorption capacity (11–18 g/g). A remarkable performance for simultaneous removal of their mixtures in milli‐Q, river, and sea water is demonstrated with efficiency for MB (≈90%), Cu (II) (>99.99%) and Hg (II) (100%) and rapid (≈30 s) uptake of organic solvents and oils. The obtained results indicate a valuable potential of proposed concept for simultaneous removal of co‐existing water pollutants. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and arsenate (As) are notorious environmental contaminants, and co‐contamination usually requires opposing treatment strategies due to their differing physico‐chemical properties. Developing adsorbents that can bind both contrasting contaminants simultaneously is desirable. Two prepared graphene materials, graphene oxide (GO) and iron‐oxide‐modified reduced‐GO (FeG), are evaluated for Cd‐ and As‐sorption, and performance is compared to a mixed‐mode commercial adsorbent. Negatively charged GO shows affinity toward cationic Cd, and positively charged FeG shows affinity toward anionic As. Sorption is pH dependent: Increase in pH‐promotes Cd‐sorption and retards As‐sorption. GO displays excellent Cd‐sorption even in acidic conditions. The maximum amounts adsorbed by GO and FeG are 782 μmol Cd g−1 and 408 μmol As g−1, respectively. Competition by calcium strongly suppresses Cd‐sorption, whereas competition by phosphate does not hinder As‐sorption. A mixture of GO and FeG demonstrates successful simultaneous sorption of Cd and As from co‐contaminated solutions, including a natural water sample, displaying greater sorption than the commercial adsorbent. Data highlight the potential application of graphene materials in effective mixed‐mode remediation of multiple contaminants (cations and anions). [ABSTRACT FROM AUTHOR]

Abstract: The unique physical and chemical properties of graphene‐based nanomaterials (GNMs) have inspired a diverse range of scientific and industrial applications. The market value of GNMs is predicted to reach $US 1.3 billion by 2023. Common to many nanomaterials, an important and unresolved question is the environmental consequences of the increases in GNMs use. The current deficiencies in studies reporting ecotoxicology data for GNMs include differences in analytical methodologies for quantification, no standardized test guidelines, differences in morphology of GNMs, the lack of Chemical Abstract Service numbers, and the quality of the reported data. The assessment of potential adverse effects on aquatic organisms typically relies on guideline values based on species sensitivity distributions (SSDs) of toxicity data. We present preliminary water quality guideline values for graphene oxide NMs in freshwaters. Data include 10 species from 7 phyla (bacteria and fungi were not included). The most sensitive organism was found to be the freshwater shrimp Palaemon pandaliformis. The derived guideline values for 99, 95, 90, and 80% species protection were 350, 600, 830, and 1300 μg/L, respectively. These results will contribute to the regulatory derivations of future water quality guideline values for graphene‐based NMs. Environ Toxicol Chem 2018;37:1340–1348. © 2018 SETAC [ABSTRACT FROM AUTHOR]

Development of next-generation sensor devices is gaining tremendous attention in both academia and industry because of their broad applications in manufacturing processes, food and environment control, medicine, disease diagnostics, security and defense, aerospace, and so forth. Current challenges include the development of low-cost, ultrahigh, and user-friendly sensors, which have high selectivity, fast response and recovery times, and small dimensions. The critical demands of these new sensors are typically associated with advanced nanoscale sensing materials. Among them, graphene and its derivatives have demonstrated the ideal properties to overcome these challenges and have merged as one of the most popular sensing platforms for diverse applications. A broad range of graphene assemblies with different architectures, morphologies, and scales (from nano-, micro-, to macrosize) have been explored in recent years for designing new high-performing sensing devices. Herein, this study presents and discusses recent advances in synthesis strategies of assembled graphene-based superstructures of 1D, 2D, and 3D macroscopic shapes in the forms of fibers, thin films, and foams/aerogels. The fabricated state-of-the-art applications of these materials in gas and vapor, biomedical, piezoresistive strain and pressure, heavy metal ion, and temperature sensors are also systematically reviewed and discussed, and their sensing performance is compared. [ABSTRACT FROM AUTHOR]

Noise is an environmental pollutant with recognized impacts on the psychological and physiological health of humans. Many porous materials are often limited by low sound absorption over a broad frequency range, delicacy, excessive weight and thickness, poor moisture insulation, high temperature instability, and lack of readiness for high volume commercialization. Herein, an efficient and robust lamella-structure is reported as an acoustic absorber based on self-assembled interconnected graphene oxide (GO) sheets supported by a grill-shaped melamine skeleton. The fabricated lamella structure exhibits ≈60.3% enhancement over a broad absorption band between 128 and 4000 Hz (≈100% at lower frequencies) compared to the melamine foam. The enhanced acoustic absorption is identified to be structure dependent regardless of the density. The sound dissipation in the open-celled structure is due to the viscous and thermal losses, whereas it is predominantly tortuosity in wave propagation and enhanced surface area for the GO-based lamella. In addition to the enhanced acoustic absorption and mechanical robustness, the lamella provides superior structural functionality over many conventional sound absorbers including, moisture/mist insulation and fire retardancy. The fabrication of this new sound absorber is inexpensive, scalable and can be adapted for extensive applications in commercial, residential, and industrial building structures. [ABSTRACT FROM AUTHOR]

Computers have become smarter, smaller, and more efficient due to the downscaling of silicon-based components. Top-down miniaturisation of silicon-based computer components is fast reaching its limitations because of physical constraints and economical non-feasibility. Therefore, the possibility of a bottom-up approach that uses molecules to build nano-sized devices has been initiated. As a result, molecular logic gates based on chemical inputs and measurable optical outputs have captured significant attention very recently. In addition, it would be interesting if such molecular logic gates could be developed by making use of ion sensors, which can give significantly sensitive output information. This review provides a brief introduction to anion receptors, molecular logic gates, a comprehensive review on describing recent advances and progress on development of ion receptors for molecular logic gates, and a brief idea about the application of molecular logic gates. [ABSTRACT FROM AUTHOR]

To treat skeletal conditions such as bone infections, osteoporotic fractures, and osteosarcoma, it would be ideal to introduce drugs directly to the affected site. Localized drug delivery from the bone implants is a promising alternative to systemic drug administration. In this study we investigated electrochemically nanoengineered Ti wire implants with titania nanotubes (TNTs), as minimally invasive drug-releasing implants for the delivery of drugs directly into the bone tissue. Since trabecular bone in vivo contains a highly interconnected bone marrow, we sought to determine the influence of marrow on drug release and diffusion. Electrochemical anodization of Ti wires (length 10 mm) was performed to create an oxide layer with TNTs on the surface, followed by loading with a fluorescent model drug, Rhodamine B (RhB). Cores of bovine trabecular bone were generated from the sternum of a young steer, and were processed to have an intact bone marrow, or the marrow was removed. RhB-loaded TNTs/Ti wires were inserted into the bone cores, which were then cultured ex vivo using the ZetOS™ bioreactor system to maintain bone viability. Release and diffusion of RhB inside the bone was monitored using fluorescence imaging and different patterns of drug transport in the presence or absence of marrow were observed. Scanning electron microscopy of the implants after retrieval from bone cores confirmed survival of the TNTs structures. Histological investigation showed the presence of bone cells adherent on the implants. This study shows a potential of Ti drug-releasing implants based on TNTs technology towards localized bone therapy. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 714-725, 2016. [ABSTRACT FROM AUTHOR]

Current development of drug microcarriers is mainly based on spherical shapes, which are not biologically favorable geometries for complex interactions with biological systems. Scalable synthesis of drug carriers with nonspherical and anisotropic shapes featuring sustained drug-releasing performances, biocompatibility, degradability, and sensing capabilities is challenging. These challenges are addressed in this work by employing Nature's optimized designs obtained from low-cost diatomaceous earth mineral derived from single-cell algae diatoms. Silica diatoms with unique shapes and 3D microcapsule morphology are converted into silicon diatom replicas with identical structure by a magnesiothermic reduction process. The results reveal that prepared silicon diatoms have a set of unique properties including favorable microcapsule structure with high surface area and micro/mesoporosity providing high drug loading, fast biodegradability, and intrinsic luminescence, which make them highly suitable for low-cost production of advanced drug microcarriers. Their sustained drug release >30 days combined with self-reporting function based on silicon luminescence properties using nonluminescent and luminescent drugs for intravitreal drug therapy is successfully demonstrated. These silicon diatoms offer promising potential toward scalable production of low-cost and advanced microcarriers for broad medical therapies, including theranostics and microrobotic guided drug delivery devices. [ABSTRACT FROM AUTHOR]

The use of conventional therapy based on a single therapeutic agent is not optimal to treat human diseases. The concept called 'combination therapy', based on simultaneous administration of multiple therapeutics is recognized as a more efficient solution. Interestingly, this concept has been in use since ancient times in traditional herbal remedies with drug combinations, despite mechanisms of these therapeutics not fully comprehended by scientists. This idea has been recently re-enacted in modern scenarios with the introduction of polymeric micelles loaded with several drugs as multidrug nanocarriers. This Concept article presents current research and developments on the application of polymeric micelles for multidrug delivery and combination therapy. The principles of micelle formation, their structure, and the developments and concept of multidrug delivery are introduced, followed by discussion on recent advances of multidrug delivery concepts directed towards targeted drug delivery and cancer, gene, and RNA therapies. The advantages of various polymeric micelles designed for different applications, and new developments combined with diagnostics and imaging are elucidated. A compilation work from our group based on multidrug-loaded micelles as carriers in drug-releasing implants for local delivery systems based on titania nanotubes is summarized. Finally, an overview of recent developments and prospective outlook for future trends in this field is given. [ABSTRACT FROM AUTHOR]

Cerebral amyloid angiopathy (CAA) is a major feature of Alzheimer's disease pathology. In CAA, degeneration of vascular smooth muscle cells (VSMCs) occurs close to regions of the basement membrane where the amyloid protein (Aβ) builds up. In this study, the possibility that Aβ disrupts adhesive interactions between VSMCs and the basement membrane was examined. VSMCs were cultured on a commercial basement membrane substrate (Matrigel). The presence of Aβ in the Matrigel decreased cell-substrate adhesion and cell viability. Full-length oligomeric Aβ was required for the effect, as N- and C-terminally truncated peptide analogues did not inhibit adhesion. Aβ that was fluorescently labelled at the N-terminus (fluo-Aβ) bound to Matrigel as well as to the basement membrane heparan sulfate proteoglycan (HSPG) perlecan and laminin. Adhesion of VSMCs to perlecan or laminin was decreased by Aβ. As perlecan influences VSMC viability through the extracellular signal-regulated kinase (ERK)1/2 signalling pathway, the effect of Aβ1–40 on ERK1/2 phosphorylation was examined. The level of phospho-ERK1/2 was decreased in cells following Aβ treatment. An inhibitor of ERK1/2 phosphorylation enhanced the effect of Aβ on cell adhesion. The studies suggest that Aβ can decrease VSMC viability by disrupting VSMC–extracellular matrix (ECM) adhesion. [ABSTRACT FROM AUTHOR]

Amyloid protein (Aβ1–40) aggregation and conformation was examined using native and sodium dodecyl sulfate/polyacrylamide gel electrophoresis, and the results compared with those obtained by atomic force microscopy, and with Congo red binding, sedimentation and turbidity assays. The amount of Aβ aggregation measured was different, depending upon the method used. Incubation for 15 min at pH 5.0 or in the presence of Fe2+, Cu2+ or Zn2+ did not alter the level of Aβ oligomers observed on SDS and native gels. However, the slow aggregation of Aβ to form high molecular mass species over 5 days was inhibited. In contrast, when Aβ aggregation was monitored using a Congo red binding assay or sedimentation assay, a rapid increase in Aβ aggregation was observed after incubation for 15 min at pH 5.0, or in the presence of Fe2+, Cu2+ or Zn2+. The low pH-, Zn2+- or Cu2+-induced Aβ aggregation measured in a turbidity assay was reversible. In contrast, a considerable proportion of the Aβ aggregation measured by native and SDS/PAGE was stable. Atomic force microscopy studies showed that Aβ aged at pH 5.0 or in the presence of Zn2+ produced larger looser rod-shaped aggregates than at pH 7.4. Aβ that had been aged at pH 7.4 was more cytotoxic than Aβ aged at pH 5.0. Taken together, the results suggest that Aβ oligomerizes via two mutually exclusive mechanisms to form two different types of aggregates, which differ in their cytotoxic properties. [ABSTRACT FROM AUTHOR]

Keywords: batteries; graphene/MoS2 composite; hydrogen evolution; solar cells; supercapacitors Graphene/MoS SB 2 sb composites emerge as exceptional candidates for energy storage applications due to the combined properties of high mechanical robustness and high electrical conductivity. Batteries, graphene/MoS2 composite, hydrogen evolution, solar cells, supercapacitors. [Extracted from the article]

A. Santos, D. Losic, and co‐workers demonstrate on page 5107 the preparation of luminescent silicon diatom replicas with unique porous microcapsule structures, by conversion from silica diatoms using a reduction process. These silicon diatoms are biodegradable and have intrinsic luminescence, sensing and drug‐releasing properties which make them outstanding candidates for low‐cost micro‐carriers for drug delivery, theranostics, and guided micro‐robotic devices. [ABSTRACT FROM AUTHOR]