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Recent strategies for the sustainable preparation of cellulose nanocrystals were comprehensively reviewed. Current challenges and future perspectives on this research topic were discussed as well.

An in situ formed antibacterial platform was designed for near-infrared controlled pharmacotherapy and photothermal therapy of drug-resistant bacteria.

Abundant pH and UV light stimuli-responsive behaviors of Gemini surfactant 12-3(OH)-12·2Br− and trans-ortho-hydroxyl cinnamic acid in aqueous solution.

The combination of strengthened lamellar liquid crystal at the oil-water interface and the HSO crystal network inside the droplet endowed the emulsion with excellent sustainable release property.

Mixed systems of the Gemini cationic surfactant trimethylene-1,3-bis (dodecyldimethylammonium bromide) (12-3-12·2Br-) and the photosensitive additives trans-methoxy sodium cinnamates with different substituent positions (trans-ortho-methoxy cinnamate, trans-OMCA; trans-meta-methoxy cinnamate, trans-MMCA; and trans-para-methoxy cinnamate, trans-PMCA) were selected for investigating the effects of the substituting position of methoxy on the system phase diagram and UV light-responsive behavior of the wormlike micelles. The differences in phase behaviors of the selected systems were analyzed by calculating the potential distribution, molecular volume, and free energy of solvation of cinnamates and the binding energies between photosensitive additives and the surfactant. The photoresponsive behaviors of wormlike micelle solutions formed in the selected systems were studied by the rheological method and UV-vis and H nuclear magnetic resonance (1H NMR) spectroscopy; the kinetics of photoisomerization of trans-OMCA, trans-MMCA, and trans-PMCA were studied by first-order derivative spectrophotometry. The results reveal that the methoxy substituent position has a great influence on the phase behavior and photosensitivity of the studied systems. In addition, the photoisomerization of the studied cinnamates follows the first-order opposite reaction laws; the different reaction rates play the decisive role in the photosensitivity of the wormlike micelles. This paper would afford a deeper understanding of the UV light-responsive mechanism at the molecular level and provide essential guidance in preparing smart materials with adjustable light sensitivity.

A series of single surfactant systems, i.e, quaternary ammonium-based gemini surfactants with different spacers and alkyl chain lengths (m-n-m; m = 12, n = 2, 3, 4, 6; n = 3, m = 12, 14, 16), halogen-free surface-active ionic liquid (HF-SAILs) with different symmetries ([Cnmim][C12H25SO4]; n = 6, 8, 10, 12), and single-chain cationic surfactants including 1-dodecyl-3-methylimidazolium bromide ([C12mim]Br) and dodecyltrimethylammonium bromide (DTAB), along with certain combinations of different surfactants (12-3-12/[C12mim]Br and 12-3-12/DTAB) were applied to an aqueous/liquid crystal interface (ALI). All the surfactants could induce an orientational transition of liquid crystals (LCs) from a planar to homeotropic state, which caused a bright-to-dark optical shift. It was proved that double-chain surfactants and the mixed surfactants inclined to adsorb at the ALI triggering the orientational transition. Inspiringly, a quicker and more sensitive dark-to-bright optical response was observed for mixed surfactant system-decorated interfaces in contact with proteins (such as bovine serum albumin (BSA), lysozyme, and trypsin) as opposed to the single surfactant systems. The ALI decorated by the 12-3-12/[C12mim]Br system was particularly efficient and exhibited the most sensitive optical response for BSA (0.01 ng mL−1). The order parameters (SCD) of surfactants tails at the interface and the free energy of proteins with 12-3-12 and [C12mim]Br were calculated, respectively. The results explain that the 12-3-12/[C12mim]Br-laden ALI shows a quicker and more sensitive optical response for BSA. This work inspired us to study mixed surfactant systems-decorated LC interfaces and further provides new insights for different chemical and biological applications.

The lower critical solution temperature (LCST) behaviour of block copolymer 2-(2-methoxyethoxy) ethyl methacrylate and oligo (ethylene glycol) methacrylate (P(MEO2MA-b-OEGMA)) was studied by molecu...

In this work, a novel redox hydrogel was proposed for ultrasensitive label-free electrochemical detection of a carcinoembryonic antigen (CEA). The redox hydrogel composed of cellulose nanocrystals (CNCs), methylene blue (MB), multi-walled carbon nanotubes (MWCNTs), and polydopamine-reduced graphene oxide-gold nanoparticles (PDA–rGO–AuNPs) was formed by electrostatic and hydrophobic interactions among these components. The larger surface to volume ratio, outstanding hydrophilicity, excellent film-forming ability and the gelatinization of CNCs provided the premise for the formation of a gel with excellent properties including larger specific surface area (101.05 m2 g−1), better adhesive ability to glassy carbon electrodes (GCEs), etc. The addition of MWCNTs to hydrogel could improve the adsorption of redox MB. The synthesized PDA–rGO–AuNPs gel was integrated into a hydrogel not only for improving the conductivity but also for providing more sites for immobilization of antibodies. The obtained CNC–MB–MWCNT–PDA–rGO–AuNPs gel was then applied to modify GCE and the gel/GCE demonstrated higher stability and exhibited a strong redox performance (current signal appeared at −0.156 V (vs. Ag/AgCl)). The immunoassay platform was constructed after the gel/GCE was incubated with anti-CEA and blocked by bovine serum albumin (BSA) in succession. The proposed immunosensor exhibited a wider linear range from 1 fg mL−1 to 200 ng mL−1 with an ultralow detection limit of 0.011 fg mL−1 (at a signal to noise ratio of 3). Furthermore, the immunosensor demonstrated higher selectivity, excellent reproducibility, remarkable stability, and better reliability for real sample analysis, which implied a promising potential for the determination of CEA in clinical application.

Precise and early detection of carcinoembryonic antigen (CEA) as a tumor marker of various cancers provides the best hope for the treatment of the deadly malignancy. Thus, the design of an immunosensor with high sensitivity is significant for early and accurate detection of CEA. In this work, a novel label-free electrochemical immunosensor was designed for the detection of CEA based on a nanostructured conductive polymer hydrogel loaded with gold nanoparticles (AuNPs). The hydrogel (BSNa-CNC-PPy) was simply prepared via in situ synthesis of polypyrrole (PPy) using cellulose nanocrystalline (CNC) and sodium benzenesulfonate (BSNa) as dopants to participate in the formation of the three-dimensional nano-hydrogel. AuNPs were further electrodeposited on the surface of BSNa-CNC-PPy gel-modified glassy carbon electrode (GCE). The immunoassay platform was obtained when the AuNPs/BSNa-CNC-PPy gel/GCE was incubated with anti-CEA and blocked by bovine serum albumin in succession. By combining the advantages of biocompatibility, nanostructure, outstanding hydrophilicity, excellent film-forming ability as well as the gelatinization of CNC, the CNC-PPy gel/GCE showed high conductivity (electroactive surface area), strong hydrophilicity, and film-forming property. The introduction of BSNa improved the conductivity of BSNa-CNC-PPy gel/GCE further due to enhanced interchain charge transport of PPy chains. The BSNa-CNC-PPy gel/GCE showed a 214% increase in electroactive surface area and the dried BSNa-CNC-PPy gel demonstrated a large specific surface area (76.59 m2 g−1), which were superior to those of existing conducting polymer hydrogels. AuNPs were apt to immobilize a mass of antibodies and accelerate electron transfer. The fabricated CEA-detecting immunosensor displayed a wide linear detection range of 1 fg mL−1 to 200 ng mL−1 and an ultralow limit of detection of 0.06 fg mL−1 (at a signal to noise ratio of 3). In addition to high sensitivity, the immunosensor exhibited excellent stability, high selectivity, good reproducibility, and strong reliability for real sample analysis. The proposed label-free electrochemical immunosensor has potential to be a diagnostic tool in clinical analysis of CEA.

Photoresponsive systems with controllable self-assembly morphologies and adjustable rheological properties have attracted widespread interest by researchers in the past few years. Among them, the p...

The presence of a highly alkaline environment or large amounts of Ca2+ in concrete exerts a great influence on the dispersion of graphene oxide (GO) particles. Therefore, the development of a highly efficient GO dispersant to adapt to complex concrete environments is important. In this work, novel phosphate-modified small molecular polydentate polymers were synthesized and used as efficient dispersants for cement and high-concentration GO solutions. The chemical structure of the polymers was confirmed by 1H NMR and IR spectroscopy, and the effect of adsorption groups on the adsorption ability of polymers was studied by using adsorption experiments and theoretical calculations. Results showed that the dispersant inositol hexaphosphate–methoxy polyether (IHP-MP) features a high adsorption equilibrium constant and strong adsorption ability. IHP-MP exhibited not only good water-reducing and slump-retaining properties but also remarkable cement hydration-retarding effects due to its numerous phosphate groups. IHP-MP could be used as an auxiliary GO dispersant with the comb polymer PCE to effectively reduce the viscosity and improve the stability of GO solutions. SEM, TGA and IR characterization indicated that IHP-MP strongly interacts with the surface groups of GO particles.

The instability in solution and aggregation-induced self-quenching of indocyanine green (ICG) have weakened its fluorescence and photothermal properties, thus inhibiting its application in practice. In this study, the cationic and anionic liposomes containing ICG were prepared based on 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dipalmitoyl

The surface electrostatic properties of the liquid foam, involving the electrokinetic (EK) phenomena in the liquid-gas interface, have significant effects on the stability of foam. Here, we established a theoretical model for ion transport in liquid films by combing the liquid flow and surface reaction. We find that the surface electrostatic properties of liquid foams were influenced unexpectedly by the pressure-induced flow. The liquid flow will induce the potential and concentration differences at flow direction. When the pressure drop increases to a certain high value, the induced potential and salt concentration difference increases, which leads to the change of the surface electrostatic properties such as zeta potential and the surface charge density. This change shows that the surface electrostatic properties of the foam films depend on the coupling of various factors including ion distribution, pressure drop, etc., which deepens our understanding of the electrostatic properties of the foam films.

Mixed systems of the Gemini cationic surfactant trimethylene-1,3-bis (dodecyldimethylammonium bromide) (12-3-12·2Br

In this work, the chromogenic catalysis of 3,3’,5,5’-tetramethylbenzidine (TMB) with horseradish peroxidase (HRP) in presence of hydrogen peroxide (H2O2), the most widely used chromogenic reaction ...

Azobenzene is one of the most commonly used photoresponsive molecules due to its light induced trans/cis transition, and it is widely used in many fields such as drug delivery. In this paper, we us...

Pulmonary administration is widely used for the treatment of lung diseases. The interaction between drug molecules and pulmonary surfactants affects the efficacy of the drug directly. The location and distribution of drug molecules in a model pulmonary surfactant monolayer under different surface pressures can provide vivid information on the interaction between drug molecules and pulmonary surfactants during the pulmonary administration. Ketoprofen is a nonsteroidal anti-inflammatory drug for pulmonary administration. The effect of ketoprofen molecules on the lipid monolayer containing 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-glycerol (DPPG) is studied by surface pressure (π)-area (A) isotherms and compressibility modulus (Cs-1)-surface pressure (π) isotherms. The location and distribution of ketoprofen molecules in a lipid monolayer under different surface pressures are explored by surface tension, density profile, radial distribution function (RDF), and the potential of mean force (PMF) simulated by molecular dynamics (MD) simulation. The introduction of ketoprofen molecules affects the properties of DPPC/DPPG monolayers and the location and distribution of ketoprofen molecules in monolayers with various surface pressures. The existence of ketoprofen molecules hinders the formation of liquid-condensed (LC) films and decreases the compressibility of DPPC/DPPG monolayers. The location and distribution of ketoprofen molecules in the lipid monolayer are affected by cation-π interaction between the choline group of lipids and the benzene ring of ketoprofen, the steric hindrance of the lipid head groups, and the hydrophobicity of ketoprofen molecule itself, comprehensively. The contact state of lipid head group with water is determined by surface pressure, which affects the interaction between drug molecules and lipids and further dominates the location and distribution of ketoprofen in the lipid monolayer. This work confirms that ketoprofen molecules can affect the property and the inner structure of DPPC/DPPG monolayers during breathing. Furthermore, the results obtained using a mixed monolayer containing two major pulmonary surfactants DPPC/DPPG and ketoprofen molecules will be helpful for the in-depth understanding of the mechanism of inhaled administration therapy.

The alkylimidazolium tetrafluoroborate ionic liquids (ILs) ([Cnmim][BF4] n = 2, 4, 6, 8, 10) and anionic surfactant sodium dodecyl sulfate (SDS) were combined together to produce effective mediums for chromogenic catalysis of tetramethylbenzidine (TMB) with horseradish peroxidase (HRP) in the presence of H2O2. The chromogenic performance, kinetic behavior, and the possible influencing mechanism for the chromogenic catalysis of HRP-H2O2-TMB were discussed in detail. Therein, the roles of ionic liquids (ILs) were highlighted by the combination of experiments and theoretical calculations. The SDS/[C4mim][BF4] combination displayed superiority in chromogenic catalysis by improving both the substrate solubility and product stability to the maximum extent possible. Furthermore, SDS/[C4mim][BF4] combination showed uniqueness for TMB in improving the chromogenic performance compared with other chromogenic substrates of HRP. Inspired by the efficient chromogenic system, an enhanced enzyme-linked immunosorbent assa...

The photoresponsive wormlike micelles constructed by Gemini surfactants and cinnamate derivatives play a great role in the field of smart materials. However, how the structure of cinnamate derivatives affects the photoresponsive behavior of micelles is still a hotspot for scientists to research. Here, three kinds of aromatic salts with different ortho-substituted groups including trans- o-methoxy cinnamate ( trans-OMCA), trans- o-hydroxy cinnamate ( trans-OHCA), and trans-cinnamate ( trans-CA) were introduced into Gemini surfactant 12-3-12·2Br- aqueous solutions to construct photoresponsive wormlike micelles through their noncovalent interactions. Their properties were researched using the rheological method, cryo-transmission electron microscopy, and 1H NMR and two-dimensional nuclear Overhauser effect spectra. The results show that these cinnamate derivatives could well construct wormlike micelles with 12-3-12·2Br-. Furthermore, subtle differences in the ortho substituents' structure have a significant effect on the photoresponsive behavior of formed wormlike micelles. Specifically, the zero viscosity (η0) of 40 mM 12-3-12·2Br-/24 mM trans-OHCA mixed solution decreases from 26.72 to 2.6 Pa·s with the shortening of the length of wormlike micelles after UV irradiation. Correspondingly, the η0 for the same ratio of 12-3-12·2Br-/ trans-OMCA decreases from 2.42 to 0.06 Pa·s and the wormlike micelles are transited into rodlike micelles and even spherical micelles after the same UV irradiation time. However, the variation of wormlike micelles in the 12-3-12·2Br-/ trans-CA system induced by UV light is not obvious with η0 being maintained at around 2.89 Pa·s. This study will help us better understand the effects of chemical groups on macrophenomena and microinteraction for micellar systems. It provides a theoretical basis for the construction of photoresponsive micelles, thus widening their application in the field of soft materials.

In this work, four types of comb-like dispersants and one linear dispersant were synthesized to explore the effect of dispersant structure on the bubble structure in water solution and mortar system for the first time. Dispersants were modified with different adsorption groups (i.e., carboxylic acid, phosphate ester, and sulfonic groups). Polymer structures were identified using gel permeation chromatography and infrared spectroscopy. Surface tension test indicated that the comb-like dispersants exhibited lower surface tension than that of the linear dispersants (NSF-2), thereby demonstrating that the polycarboxylate superplasticizer (PCE) solutions possessed high surface activity. The analysis of the foamability and foam stability of the comb-like and linear dispersants were comprehensively investigated at different concentrations. Comb-like dispersants possessed higher foam height and better foamability performance than those of the linear dispersants. The bubbles of the dispersant PCE-3 were smaller in terms of the mean area and possessed higher number of bubbles than those of the other dispersants, which may be essential in reducing the viscosity of the slurry. A similar result was also obtained in the mortar system tested using the AVA instrument for PCE-3 and NSF-2. Adsorption and rheological behavior test indicated that comb-like dispersant PCE-3 is the most effective in reducing the viscosity of the slurry among all the dispersants tested. This result is consistent with that of the foamability experiment.

Machine learning (ML) methods were applied to predict the capacitance of carbon-based supercapacitors. Hundreds of published experimental datasets are collected for training ML models to identify the relative importance of seven electrode features. This present method could be used to predict and screen better carbon electrode materials.

Liquid crystals (LCs) are widely used for drug delivery due to their controlled and sustained drug release properties. In this paper, drug crystallization encapsulated liquid crystal emulsion, a novel drug delivery system, was proposed. The lamellar liquid crystals formed by hydrogenated lecithin, which are similar to the skin stratum corneum lipid structure, are adopted as the drug carrier to encapsulate non-steroidal anti-inflammatory drugs (NSAIDs). As the model drug, ketoprofen exists in the hydrophobic core of emulsion as a drug crystal when squalane is used as the oil phase. The microstructure, sustained drug release behaviors, physicochemical property and biocompatibility of the system were examined by polarized light microscopy, rheological measurements, differential scanning calorimetry, X-ray diffraction, small-angle X-ray scattering, in vitro release study, and in vitro cellular cytotoxicity assay. The results have shown that the novel system lowers the drug crystal melting point and improves the thermal stability of liquid crystal structure. Besides, the excellent biocompatibility and sustained release property through the additional dissolution step of drug crystal show its application potentials in the topical cosmeceuticals. The results will also be helpful for in-depth understanding of the physical state of encapsulated drug in the liquid crystal carrier systems.

A new lubricating coating with functionalized graphene oxide (fGO) consisting of graphene oxide (GO) with different oxidation degrees, n-octylamine basal plane functionalized GO (bGO), and edge functionalized GO (eGO) was developed with or without 3-aminopropyltrimethoxysilane (APTMS) to reduce friction in macroscale contact with water. The optimal preparation condition of the coating was obtained by the single factor evaluation of a series of factors (20 % APTMS aqueous solution, 12 h immersion time, 0.05 mg/mL GO aqueous solution, and 100 °C curing temperature). The effect of the oxidation degree and functionalization of GO on the friction-reducing and anti-wear behavior of the coating was explored. The coatings with a higher GO oxidation degree exhibited better friction-reduction and anti-wear performance. In addition, the friction-reducing capability of the APTMS-bGO coating was greater than that of APTMS-eGO.

Photoresponsive systems with controllable self-assembly morphologies and adjustable rheological properties have attracted widespread interest by researchers in the past few years. Among them, the photoresponsive systems consisting of

Mixed surfactants have potential applications in various fields. The understanding and prediction of their macro- and microscopic properties are of great importance in the designing of these materi...

The deposition and transport of toxicants on pulmonary surfactant are important processes in human health and medical care. We have introduced classical density functional theory (CDFT) to provide insight into this process. Nine typical toxicants in PM2.5 were considered, and their free energy and structural information have been examined. The free energy profile indicates that PbO, As2O3, and CdO are the three toxicants most easily deposited in the pulmonary alveolus, which is consistent with survey data. CuO appears to be the easiest toxicant to transport through the surfactant. Structural analysis indicates that the toxicants tend to pass through the surfactant with rotation. The configuration of the pulmonary surfactant was examined by extending our previous work to polymer systems, and it appears that both the configurational entropy and the direct interaction between the surfactant and the toxicant dominate the configuration of the pulmonary surfactant.

Photoresponsive systems with adjustable self-assembly morphologies and tunable rheological properties have aroused widespread concern of researchers in recent years because of their prospect applications in controlled release, microfluidics, sensors, and so forth. In this paper, we combine a cationic Gemini surfactant 12-3-12·2Br– and trans-2-methoxy-cinnamate (trans-OMCA) together to create a representative UV-responsive self-assembly system. The system displays abundant self-assembly behaviors, and the self-assemblies with different states and different scales including wormlike micelles, vesicles, and lyotropic liquid crystals (LCs) as well as an aqueous two-phase system (ATPS) are observed even at lower surfactant concentration. The UV-responsive behavior of the formed self-assemblies is investigated systematically. The results have shown that the photoisomerization of OMCA from trans form to cis form under UV light irradiation alters the hydrophobicity and steric hindrance effect of OMCA and thus aff...

The interaction between star-shaped copolymer poly(2-(dimethylamino)ethyl methacrylate-b-2-(2-methoxyethoxy)ethyl methacrylate) (CDPDPM) and anionic surfactant sodium dodecyl sulfate (SDS) in aqueous solutions are investigated by using fluorescence and dynamic light scattering (DLS) techniques. The effects of nonionic surfactant dodecyl β-D-maltopyranoside (C12G2) and salts including inorganic salt ammonium bromide (NH4Br) and organic salt tetra-n-butylammonium bromide (Bu4NBr) on the interaction between CDPDPM and SDS have been explored systematically. The results have suggested that SDS molecules can bind on CDPDPM by electrostatic interaction between the positively charged CDPDPM and negatively charged SDS and thus weaken the binding ability of CDPDPM to water molecules. CDPDPM exhibits temperature-responsive aggregation behavior in aqueous solution gradually with the increase of SDS concentration and the lower critical solution temperature (LCST) decreases correspondingly. The introduction of nonionic surfactant C12G2 changes the interaction between CDPDPM and SDS significantly by participate the formation of complexes and the stability of the CDPDPM/SDS complexes declines leading to the chance of forming larger complexes is deprived at higher temperature. The addition of NH4Br to the CDPDPM/SDS system can retard the binding of SDS on the polymer chains because of electrostatic shielding. Correspondingly, LCST is higher and the formed aggregates are smaller. For CDPDPM/Bu4NBr/SDS system, the phenomenon is similar to that of the CDPDPM/C12G2/SDS system. This should be attributed to the nature of Bu4N+, possesses not only positive charges but also certain hydrophobicity, and thus Bu4N+ has the ability to participate and facilitate the formation of SDS micelles. Obviously, the LCST of the mixed system can be tailored by adjusting the system composition on purpose.

The gelation behavior and properties of sodium deoxycholate (NaDC) and L-aspartic acid (Asp) in aqueous solution were investigated in detail at 25 °C. The linear polymer poly(2-(2-methoxyethoxy)ethyl methacrylate-co-oligo-(ethylene glycol) methacrylate) (P(MEO2MA90-co-OEGMA10)) and star-shaped polymer poly(2-(dimethylamino)ethyl methacrylate-b-2-(2-methoxyethoxy)ethyl methacrylate) (CDPDPM) were introduced in NaDC/Asp hydrogels for exploring the effects of polymers on the properties of NaDC/Asp hydrogels and the mechanism underlying gelation processes by polymers was proposed. The hydrogels were characterized by phase behavior observation, polarized optical microscopy (POM), cryogenic scanning electron microscopy (cryo-SEM), X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and rheological measurements. Moreover, the adsorption performances of hydrogels with and without polymers to methylene blue (MB) were studied using a UV-vis spectrometer. The results indicated that the transition from sol to gel state was observed with an increase in the Asp concentration in the system. Both linear and star-shaped polymers can participate in the formation of a gel network structure, so that the density of network structure and the mechanical strength of hydrogels increased. Furthermore, it was found that the viscoelasticity of the CDPDPM-containing hydrogel was much higher than that of the P(MEO2MA90-co-OEGMA10)-containing hydrogel under the same condition, indicating that CDPDPM performed better in strengthening the network structure of the hydrogels than P(MEO2MA90-co-OEGMA10) due to the special structure that provided more binding sites for hydrogen bonding and stronger hydrophobicity that inhibited the swelling and dissolution of hydrogels. On coming in contact with the MB solution, the CDPDPM-containing hydrogel can adsorb MB and maintain the hydrogel state for recycling. On the contrary, the NaDC/Asp hydrogel dissolved and P(MEO2MA90-co-OEGMA10)-containing hydrogel collapsed in the MB solution. The properties of the hydrogels are expected to be tailored by introducing polymers with different properties, including the charge numbers, the number of available binding sites, and hydrophobic properties.

MoS2 coating is an effective way to suppress the growth of lithium dendrites, but the study of the layer spacing effect is still lacking. In this work, the diffusion and adsorption of lithium ions on the MoS2 were studied by multiscale simulations. The transport of lithium ions on the MoS2 was investigated by a continuum method, which shows that the smaller layer spacing of 1 nm can enhance the ion diffusion. The QDFT method was used to study the lithium ions transport on 1T- and 2H- MoS2 with layer spacing of 0.65 nm - 1.15 nm. Results indicate that lithium dendrites are more difficult to grow on 2H- MoS2. For both types of MoS2, enlarged layer spacing can reduce lithium dendrites growth and 0.75 nm is the most suitable interlayer distance for MoS2 expanding. We hope our results can provide guidance to the synthesis of dendrite-free lithium metal batteries.

Polymer superplasticizer and residual polyether have a key effect on the quantity and size distribution of air-voids in hardened concrete. In this study, the surface activity and foam properties of polydentate phosphonate-modified polymers RM-1 and RM-2 in aqueous solution were studied. Results revealed that the propylene oxide (PO) units in the polymer structure affected the foaming properties of polymers. The compounding performance of polymers RM-1 and RM-2 with ester-type polycarboxylate superplasticizer (PCE-1) in aqueous solution and cement mortar was also studied. This kind of phosphonate-modified polymers can be used as excellent concrete rheological modifier agents because they generate many small bubbles when compounded with PCE-1. Analysis of the foam properties of polymer RM-1 in aqueous solution and cement pore solution revealed that the calcium ions in cement pore solution are beneficial to stabilize the bubbles produced by the polymer. This study provides a new way to study the properties of phosphonate admixture and its combination with PCE from the perspective of bubble and rheology in aqueous solution and cement mortar.

A series of star-shaped block copolymers (CDPDPM) of 2-(dimethylamino)ethyl methacrylate (DMAEMA) and 2-(2-methoxyethoxy)ethyl methacrylate (MEO2MA) with tunable stimuli-responsive behavior are synthesized via sequential atom transfer radical polymerization (ATRP) with the 2-bromoisobutyryl-terminated β-cyclodextrin (β-CD) as a core. The properties of these star-shaped copolymers are characterized by FT-IR, NMR and GPC analyses. Meanwhile, the thermo-sensitive behaviors of CDPDPM with different compositions and pH values are investigated by dynamic light scattering (DLS) and UV–vis measurements. The results have shown that the synthesized polymer CDPDPM exhibits both pH- and thermo-responsive behaviors in aqueous solutions. The star-shaped copolymers with the nearly equal mole fraction of DMAEMA and MEO2MA show two-step thermo-induced aggregation behavior in water at a pH near the isoelectric point (IEP), which corresponds to the formation of branch aggregates and large aggregates consisting of clustered branch aggregates, respectively. The mole fraction of DMAEMA and MEO2MA in polymer affects the thermal-responsive behaviors of polymer itself. Moreover, the micellar behaviors of the synthesized copolymers in aqueous solution are explored. The aggregation process of the copolymer can be generalized into intramolecular aggregation of the hydrophobic chains (corresponding to CI), formation of premicelles, the aggregation and rearrangement of the premicelles (namely CMC), as well as the formation of multicore structures. The CI and CMC values depend on both the MEO2MA molar fraction and the carbon backbone length of polymers. The aggregation number (N) and the sizes of polymer micelles (Dh) vary with the polymer composition, polymer concentration and ambient environment.

The traditional surfactant sodium dodecyl sulfate (SDS) and ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate ([Emim][BF 4 ]) have been combined to create a novel efficient medium for chromogenic catalysis of 3,3′,5,5′-tetramethylbenzidine with horseradish peroxidase in presence of H 2 O 2 . The results have shown the [Emim][BF 4 ] in the mediums can promote the rate of formation of the blue chromogen, the SDS is responsible for the stabilization of the blue chromogen due to the electrostatic attraction between positively charged blue chromogen and the negatively charged surfactant. The SDS/[Emim][BF 4 ] combination not only enhance catalytic activity of HRP remarkably but also stabilize the blue chromogen formed in the HRP oxidation of the substrate TMB compared to the conventional medium. Based on the superior combination of SDS and [Emim][BF 4 ], the colorimetric assay for detecting HRP activity and H 2 O 2 concentration was established. This work demonstrates a novel efficient medium for chromogenic catalysis with potential applications in biosensors and clinical diagnosis.

The authors describe biocompatible nanomicelle based drug carriers that can be used for simultaneous (a) fluorescence tracking, (b) pH-controlled release of the cancer drug doxorubicin (DOX), and (c) targeting the folate receptor. The pH-sensitive triblock copolymer is composed of poly-2-(diisopropylamino) ethyl methacrylate and methoxypoly (ethylene glycol) which were prepared by radical polymerization and ‘click’ chemistry. The copolymers undergo self-assembly to form spherical micelles with diameters between 100 and 200 nm and a pH-trigger capability at pH values from 5.8 to 6.2. The micelles enabled DOX to be released at pH 5.0 at a much higher rate than at pH 7.4. Studies on cellular uptake revealed selective internalization of the DOX-loaded nanomicelles into HeLa cells where they can be imaged fluorometrically. Quantitative analysis of the green fluorescence indicated that the FITC-labeled micelles possess a transfection efficiency of about 79% while that of the nanomicellles with folate is only ∼40% under the same conditions. Confocal laser scanning microscopy indicates that the micelles invade the lysosome of HeLa cells and that the DOX released by micelles causes strong cell lethality. In our preception, this work provides useful insights in terms of designing multifunctional drug carriers and of improving the applicability of copolymer micelles for drug delivery systems.

The principal problem in the area of drug delivery is achieving better selectivity and controllability. A new core–shell nanoparticle composite (denoted MSN@Tf@Polymer) with dual-pH-sensitivity has been prepared as a drug carrier for intracellular drug delivery and release. MSN@Tf@Polymer consists of mesoporous silica nanoparticles (MSN), green-transferrin (Tf) and diblock copolymer (poly-2-diisopropylamino ethylmethacrylate-b-methoxy-poly ethyleneglycol: mPEG45-PDPAn). The core–shell structure is self-assembled layer by layer. Results show that nearly 80% doxorubicin hydrochloride (DOX) loaded in MSN@Tf@Polymer could be released in 5 h at pH 5.0, which is an improvement from the results obtained at pH 6.5 and pH 7.4. MTT assay and fluorescence inversion microscope experiments indicate that MSN@Tf is successfully taken up by liver cancer cells (Huh7) without apparent cytotoxicity, and Tf has strong intensity of fluorescence for subcellular localization. Confocal laser scanning microscopy (CLSM) experiments indicate that MSN@Tf@Polymer is able to enter the lysosome of the tumor cells. Furthermore, cell apoptosis experiments prove that DOX loaded in MSN@Tf@Polymer has the best anti-tumor effect compared with free DOX and DOX in bare MSN. MSN@Tf@Polymer has high biocompatibility, enhanced drug loading, site-specific delivery and in situ stimulus release and will also hopefully be applied as an intracellular drug delivery system.

One important thing in tumor chemotherapy is to develop the targeting, precise timing, and quantitative drug delivery/release system. According to the weak acid of tumor extracellular environment, a pH-sensitive bola-type triblock copolymer (PEG m -PDPA n -PEG m ) was synthesized and mixed with phospholipid to form functional hybrid liposomes (liposome@Bola). When compared to pure liposome, the stability of the liposome@Bola was enhanced greatly and the drug leakage was inhibited at pH 7.4. However, under pH 6.0, the drug released quickly through the nanopores on the lipid bilayer created by the escape of copolymers. Under a strongly acidic environment, the drug release of liposome@Bola could be blocked again due to the coverage of free copolymers. The kinetic curves of drug release had been modeled by using some frequently used models. It was found that the release of liposome@Bola under pH 6.0 was biphasic with a slow release by means of membrane permeation and a rapid second phase which was released through nanopores on liposome membrane. The results indicated that the pH-responsive liposome@Bola could be expected to be a good potential in controllable drug delivery system.

One growing issue is how to use the weakly acidic conditions in endosomes/lysosomes for designing highly pH-sensitive drug carriers to deliver chemotherapeutic drugs accurately. In this paper, pH-sensitive amphiphilic triblock copolymers PEG8-PDPAn-PEG8 (n = 30, 50 and 100) were synthesized. Micelles composed of the copolymers were found to enter into lysosomes using a lysosome tracker method. The pH-sensitivity makes the micelles stable at pH 7.4 but swell and become looser at pH 6.0 due to protonation. Then, doxorubicin (DOX) was efficiently encapsulated in the hydrophobic cores of the micelles and released continuously in a weakly acidic environment. Cell toxicity assays were carried out using 2 human cell lines (HEK293 and Huh7) and showed good cyto-compatibility. In vitro cell viability tests proved that the DOX-loaded micelles could be more efficiently taken up by Huh7 tumor cells than free DOX, as well as actively trigger intracellular DOX release. Furthermore, in addition to small molecules (DOX), the copolymer micelles could also deliver macromolecules (such as transferrin, which could not enter into cells by itself) into lysosomes/endosomes. These nontoxic and multifunctional micelles can serve as a promising treatment candidate for efficient intracellular drug delivery and real-time monitoring.