Alternating Magnetic Field Controlled Targeted Drug Delivery Based on Graphene Oxide-Grafted Nanosupramolecules

Graphene oxide (GO)-grafted nanosupramolecules have recently emerged as neoteric nano drug carriers in the therapy of refractory diseases. Herein, a multicomponent nanosupramolecular drug carrier based on a targeted peptide and magnetic GO is reported, the drug-release behavior of which can be regulated by an alternating magnetic field (AMF). This multicomponent nanosupramolecular carrier is composed of β-cyclodextrin (β-CD)/nickel nanoparticle-modified graphene oxide (GONiCD) and mitochondrial ion-targeting peptide (MitP)-grafted hyaluronic acid (HAMitP). Owing to the host–guest interaction between β-cyclodextrin and the cyclohexyl groups on MitP, GONiCD and HAMitP could form supramolecular assemblies during the doxorubicin (Dox) loading process, which not only remarkably enhances the drug-loading capacity, but also improves the drug-release efficiency under AMF stimulus. During co-incubation with tumor cells, the Dox-loaded assemblies could strongly target the tumor mitochondria and damage both the mitochondria and the nuclei, owing to Dox release from the assemblies induced by AMF. This study sheds light on the exploration of peptide caps for controlled drug loading/release of supramolecular nanocarriers for efficient drug delivery and anticancer therapy.     

One‐Pot Synthesis of Pomegranate‐Structured Fe3O4/Carbon Nanospheres‐Doped Graphene Aerogel for High‐Rate Lithium Ion Batteries

A unique hierarchically nanostructured composite of iron oxide/carbon (Fe₃O₄/C) nanospheres‐doped three‐dimensional (3D) graphene aerogel has been fabricated by a one‐pot hydrothermal strategy. In this novel nanostructured composite aerogel, uniform Fe₃O₄ nanocrystals (5–10 nm) are individually embedded in carbon nanospheres (ca. 50 nm) forming a pomegranate‐like structure. The carbon matrix suppresses the aggregation of Fe₃O₄ nanocrystals, avoids direct exposure of the encapsulated Fe₃O₄ to the electrolyte, and buffers the volume expansion. Meanwhile, the interconnected 3D graphene aerogel further serves to reinforce the structure of the Fe₃O₄/C nanospheres and enhances the electrical conductivity of the overall electrode. Therefore, the carbon matrix and the interconnected graphene network entrap the Fe₃O₄ nanocrystals such that their electrochemical function is retained even after fracture. This novel hierarchical aerogel structure delivers a long‐term stability of 634 mA h g^?1 over 1000 cycles at a high current density of 6 A g^?1 (7 C), and an excellent rate capability of 413 mA h g^?1 at 10 A g^?1 (11 C), thus exhibiting great potential as an anode composite structure for durable high‐rate lithium‐ion batteries.     

The Reductive Dehydration of Cellulose by Solid/Gas Reaction with TiCl4 at Low Temperature: A Cheap,Simple, and Green Process for Preparing Anatase Nanoplates and TiO2/C Composites

Metal oxides and metal oxide/carbon composites are entering the development of new technologies and should therefore to be prepared by sustainable chemistry processes. Therefore, a new aspect of the reactivity of cellulose is presented through its solid/gas reaction with vapour of titanium(IV) chloride in anhydrous conditions at low temperature (80 °C). This reaction leads to two transformations both for cellulose and titanium(IV) chloride. A reductive dehydration of cellulose is seen at the lowest temperature ever reported and results in the formation of a carbonaceous fibrous solid as the only carbon‐containing product. Simultaneously, the in situ generation of water leads to the formation of titanium dioxide with an unexpected nanoplate morphology (ca. 50 nm thickness) and a high photocatalytic activity. We present the evidence showing the evolution of the cellulose and the TiO₂ nanostructure formation, along with its photocatalytic activity. This low‐temperature process avoids any other reagents and is among the greenest processes for the preparation of anatase and also for TiO₂/carbon composites. The anisotropic morphology of TiO₂ questions the role of the cellulose on the growing process of these nanoparticles.     

Modification of the Solution Behavior of Pd12L24 Metal–Organic Nanocages via PEGylation

The dilute solutions behaviors of Pd₁₂L₂₄ metal–organic nanocage and its two PEGylated derivatives are explored. The basic nanocages can self‐assemble into vesicle‐like blackberry structures in polar solvents via counterion‐mediated attraction, whereas the PEGylated nanocages always stay as discrete ions under the same conditions, demonstrating that the PEGylation can improve the stability of the single nanocages. In addition, larger nanocages are found to self‐assemble in less polar solvents.     

Plasmonic nanostructures for local field enhancement in the UV region

In this work we describe an ultraviolet subwavelength focusing in plasmonic nanostructures. A system which provides a 20–25 times local field enhancement at a wavelength of 350 nm is proposed. This system represents a metalized V-shaped groove in a surface of a dielectric medium. Subwavelength focusing is achieved by a plasmon wave propagation along the surface of metal film and by the transfer of electromagnetic field through the dielectric medium. The influence of system parameters on a local field enhancement is investigated. A simplified model that allows for determining the geometric parameters of an optimized resonator is proposed.     

Well‐Defined Functional Linear Aliphatic Diblock Copolyethers: A Versatile Linear Aliphatic Polyether Platform for Selective Functionalizations and Various Nanostructures

Low‐temperature anionic ring‐opening homopolymerizations and copolymerizations of two glycidol derivatives (allyl glycidyl ether (AGE) and ethoxyethyl glycidyl ether (EEGE)) are studied using a metal‐free catalyst system, 3‐phenyl‐1‐propanol (PPA) (an initiator) and 1‐tert‐butyl‐4,4,4‐tris(dimethylamino)‐2,2‐bis[tris‐(dimethylamino)phosphoranylidenamino]‐2Λ⁵,4Λ⁵‐catenadi(phosphazene) (t‐Bu‐P₄) (a promoter) in order to obtain well‐defined functional linear polyethers and diblock copolymers. With the aid of the catalyst system, AGE is found to successfully undergo anionic ring‐opening polymerization (ROP) even at room temperature (low reaction temperature) without any side reactions, producing well‐defined linear AGE‐homopolymer in a unimodal narrow molecular weight distribution. Under the same conditions, EEGE also undergoes polymerization, producing a linear EEGE‐homopolymer in a unimodal narrow molecular‐weight distribution. In this case, however, a side reaction (i.e., chain‐transfer reaction) is found to occur at low levels during the early stages of polymerization. The chemical properties of the monomers in the context of the homopolymerization reactions are considered in the design of a protocol used to synthesize well‐defined linear diblock copolyethers with a variety of compositions. The approach, anionic polymerization via the sequential step feed of AGE and EEGE as the first and second monomers, is found to be free from side reactions at room temperature. Each block of the obtained linear diblock copolymers undergoes selective deprotection to permit further chemical modification for selective functionalization. In addition, thermal properties and structures of the polymers and their post‐modification products are examined. Overall, this study demonstrates that a low‐temperature metal‐free anionic ROP using the PPA/t‐Bu‐P₄ catalyst system is suitable for the production of well‐defined linear AGE‐homopolymers and their diblock copolymers with the EEGE monomer, which are versatile and selectively functionalizable linear aliphatic polyether platforms for a variety of post‐modifications, nanostructures, and their applications.