Sponge Phase Producing Porous CeO2 for Catalytic Oxidation of CO

The aggregation behavior of mixtures of the alkaline amino acid L ‐Arginine (L ‐Arg) and bis(2‐ethylhexyl)phosphoric acid (DEHPA) in water was studied in detail. At a fixed L ‐Arg concentration, a phase sequence of micellar phase (L₁ phase), vesicle phase (L_αv phase), planar lamellar phase (L_αl phase), and sponge phase (L₃ phase) was obtained with increasing DEHPA concentration due to changes in the packing parameter. The phase transition of the lamellar structures was determined by freeze‐fracture TEM and ²H NMR spectroscopy. Rheological measurements reflected the phase transition through significant variations of both the elastic modulus and the viscous modulus. Porous CeO₂ materials were produced by utilizing the L₃ phase as template, and the porous CeO₂ exhibited excellent catalytic oxidation activity toward CO due to its high surface area, which provides more active sites for CO conversion.     

Size‐Regulable Vesicles Based on Anion–π Interactions

Taking tetraoxacalix[2]arene[2]triazine as a functionalization platform, a series of new amphiphilic molecules were synthesized in 18 to 53 % yields by using a fragment coupling protocol. These amphiphilic molecules self‐assembled into stable vesicles in a mixture of THF and water, with the surface of the vesicles engineered by electron‐deficient cavities. Various anions are able to selectively influence the size of self‐assembled vesicles, following the order of F^?<ClO₄^?<SCN^?<BF₄^?<Br^?<Cl^?<NO₃^?, as revealed by DLS measurements. Such a sequence was independent with the hydration cost and in agreement with the binding strength of anions with tetraoxacalix[2]arene[2]triazine host molecule, indicating that the anion–π interaction most probably competed over other possible weak interactions and accounted for this interesting selectivity. In addition, the chloride permeation process across the membrane of the vesicles was also preliminarily studied by means of fluorescent experiments. This study, in addition to providing the potentiality of heteracalixaromatics as new models to construct functional vesicles, opens a new avenue to study the anion–π interactions in aqueous and also potentially in living systems.     

Functionalized Membranes for Photocatalytic Hydrogen Production

Functionalized vesicles for photocatalytic hydrogen production in water have been prepared by co‐embedding of amphiphilic photosensitizers and a hydrogen‐evolving catalyst in phospholipid membranes. The self‐assembly allows a simple two‐dimensional arrangement of the multicomponent system with close spatial proximity, which gave turnover numbers up to 165 for the incorporated amphiphilic cobaloxime water reduction catalyst 3 b under optimized conditions in purely aqueous solution. Superior photocatalytic activity in fluid membranes indicates that mobility and dynamic reorganization of catalytic subunits in the membrane promote the visible‐light‐driven hydrogen production. The functionalized membranes represent nanostructured assemblies for hydrogen production in aqueous solution mimicking natural photosynthesis.     

Voltage‐Driven Reversible Insertion into and Leaving from a Lipid Bilayer: Tuning Transmembrane Transport of Artificial Channels

Three new artificial transmembrane channel molecules have been designed and synthesized by attaching positively charged Arg‐incorporated tripeptide chains to pillar[5]arene. Fluorescent and patch‐clamp experiments revealed that voltage can drive the molecules to insert into and leave from a lipid bilayer and thus switch on and off the transport of K⁺ ions. One of the molecules was found to display antimicrobial activity toward Bacillus subtilis with half maximal inhibitory concentration (IC₅₀) of 10 μM which is comparable to that of natural channel‐forming peptide alamethicin.     

Self‐Assembly of DNA–Oligo(p‐phenylene‐ethynylene) Hybrid Amphiphiles into Surface‐Engineered Vesicles with Enhanced Emission

Surface‐addressable nanostructures of linearly π‐conjugated molecules play a crucial role in the emerging field of nanoelectronics. Herein, by using DNA as the hydrophilic segment, we demonstrate a solid‐phase “click” chemistry approach for the synthesis of a series of DNA–chromophore hybrid amphiphiles and report their reversible self‐assembly into surface‐engineered vesicles with enhanced emission. DNA‐directed surface addressability of the vesicles was demonstrated through the integration of gold nanoparticles onto the surface of the vesicles by sequence‐specific DNA hybridization. This system could be converted to a supramolecular light‐harvesting antenna by integrating suitable FRET acceptors onto the surface of the nanostructures. The general nature of the synthesis, surface addressability, and biocompatibility of the resulting nanostructures offer great promises for nanoelectronics, energy, and biomedical applications.     

Cationic Vesicles Based on Amphiphilic Pillar[5]arene Capped with Ferrocenium: A Redox‐Responsive System for Drug/siRNA Co‐Delivery

A novel ferrocenium capped amphiphilic pillar[5]arene (FCAP) was synthesized and self‐assembled to cationic vesicles in aqueous solution. The cationic vesicles, displaying low cytotoxicity and significant redox‐responsive behavior due to the redox equilibrium between ferrocenium cations and ferrocenyl groups, allow building an ideal glutathione (GSH)‐responsive drug/siRNA co‐delivery system for rapid drug release and gene transfection in cancer cells in which higher GSH concentration exists. This is the first report of redox‐responsive vesicles assembled from pillararenes for drug/siRNA co‐delivery; besides enhancing the bioavailability of drugs for cancer cells and reducing the adverse side effects for normal cells, these systems can also overcome the drug resistance of cancer cells. This work presents a good example of rational design for an effective stimuli‐responsive drug/siRNA co‐delivery system.     

Salt,Shake, Fuse—Giant Hybrid Polymer/Lipid Vesicles through Mechanically Activated Fusion

Large (200 nm) poly(ethylene oxide)‐b‐poly(butadiene) polymer vesicles fuse into giant (>1 μm) vesicles with mild agitation in dilute aqueous NaCl solutions. This unusual effect is attributed to the salt‐induced contraction of the poly(ethylene oxide) corona, reducing steric resistance between vesicles and, with agitation, increasing the probability of contact between the hydrophobic cores of adjacent membranes. In addition, NaCl and agitation facilitated the creation of giant hybrid vesicles from much smaller homogeneous polymersomes and liposomes. Whereas lipid vesicles do not readily fuse with each other under the same circumstances, they did fuse with polymersomes to produce hybrid polymer/lipid vesicles.     

Self‐Propelled Janus Mesoporous Silica Nanomotors with Sub‐100 nm Diameters for Drug Encapsulation and Delivery

The synthesis of an innovative self‐propelled Janus nanomotor with a diameter of about 75 nm that can be used as a drug carrier is described. The Janus nanomotor is based on mesoporous silica nanoparticles (MSNs) with chromium/platinum metallic caps and propelled by decomposing hydrogen peroxide to generate oxygen as a driving force with speeds up to 20.2 μm s^?1 (about 267 body lengths per second). The diffusion coefficient (D) of nanomotors with different H₂O₂ concentrations is calculated by tracking the movement of individual particles recorded by means of a self‐assembled fluorescence microscope and is significantly larger than free Brownian motion. The traction of a single Janus MSN nanomotor is estimated to be about 13.47×10^?15 N. Finally, intracellular localization and drug release in vitro shows that the amount of Janus MSN nanomotors entering the cells is more than MSNs with same culture time and particle concentrations, meanwhile anticancer drug doxorubicin hydrochloride loaded in Janus MSNs can be slowly released by biodegradation of lipid bilayers in cells.     

Self-assembly behavior of copolymers with super segregated structure containing fluorinated segments

Copolymers with super segregated structure of hydrophilic methoxy poly（ethylene glycol） （mPEG） and fluorophilic poly（1H,1H,2H,2H-perfluorodecyl acrylate） （PFA） were prepared. And just because of this super segregated structure which was resulted from the extremely strong incompatibility between the two blocks, several interesting self- assembly behaviors of the copolymers were displayed and studied under different conditions. Transmission electron microscope （TEM） showed that with the increase of PFA in the polymerization system, the incompatibility in this super segregated structure became stronger, and the self-assembly behavior changed from ball-like or rod-like to vesicles, and finally collapsed to sheet-like. The self-assembly behavior changed likewise when the initial concentration increased. And the interesting formation of these barrel-like and spindle-like vesicles was finally studied with different cooling speeds. It＇s finally found that with this super segregation structure, these new self-assembly morphology might be formed due to the extremely strong incompatibility between mPEG and PFA segments.