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Abstract: For the first time, the interaction of casein micelle (CM) with gold nanoparticles (GNPs) was studied using TEM, UV–visible, FTIR and fluorescence spectroscopy methods. The results show that GNPs bind to CM surface, leading to the formation of GNP–CM conjugates. GNPs exhibit similar particle diameters, and the CM structure is retained in GNP–CM conjugates. Furthermore, GNP–CM conjugates display good stability against salt concentration and pH. The combination of these measurements suggests that GNPs presumably bind to CM surfaces via complexation with the carboxylate or amine groups on CM surfaces, but not by electrostatic action. [Copyright &y& Elsevier]

Abstract: The interactions of hemoglobin with glutamic acid-based gemini surfactants (L2G2C n ) and with n-dodecylammonium α-glutamate (GDA) have been studied with isothermal titration microcalorimetry, fluorescence spectroscopy, UV–vis spectroscopy, and circular dichroism. The results indicate that GDA monomer can make the hemoglobin denatured, and that when the concentration of GDA is higher than cmc, heme monomer is released from the hydrophobic cavity of hemoglobin. On the other hand, L2G2C n surfactants can also interact with hemoglobin. Compared with GDA, L2G2C n have a much smaller binding ability with hemoglobin, and the circular dichroism spectra results show that the secondary structure of hemoglobin is possibly stabilized by a small amount of L2G2C n , which may generate hydrophobic linkages between the nonpolar residues of hemoglobin. However, with further addition of L2G2C n , the secondary structure of hemoglobin is unfolded, and the percentage of α helix in hemoglobin molecule is decreased. In addition, the L2G2C n surfactant with a longer spacer can reduce the denaturing degree of hemoglobin. [Copyright &y& Elsevier]

Abstract: In the sodium dodecyl sulfate (SDS)/n-pentanol (n-C5H11OH)/water (H2O) system, LL is the coexisting region of W/O and O/W or bicontinuous microemulsions. In the LL region, the system separates into two phases (the upper phase and the lower phase) spontaneously. The distribution and structural behavior of hemoglobin (Hb) between the upper and lower phases in SDS/n-C5H11OH/H2O system were studied by UV–vis and circular dichroism (CD) spectroscopy. The results indicate that different structures of the two phases bring the conformational change of Hb. The addition of Hb results in the redistribution of SDS between the upper and lower phases. [Copyright &y& Elsevier]

Abstract: The interaction of the anionic surfactant sodium dodecyl sulfate (SDS) with 2.0 mg/ml casein was first investigated using isothermal titration calorimetry (ITC), dynamic light scattering (DLS), and fluorescence spectra. ITC results show that individual SDS molecules first bind to casein micelles by the hydrophobic interaction. The micelle-like SDS aggregate is formed on the casein chains when SDS concentration reaches the critical aggregation concentration (), which is far below the critical micellar concentration (cmc) of SDS in the absence of casein. With the further increase of SDS concentration to the saturate binding concentration , SDS molecules no longer bind to the casein chains, and free SDS micelles coexist with casein micelles bound with SDS aggregates in the system. DLS results show that the addition of SDS leads to an increase in the hydrodynamic radius of casein micelles with bound surfactant at SDS concentration higher than 4 mM, and also an increase in the casein monomer molecule (or submicelles) at SDS concentration higher than 10 mM. Fluorometric results suggest the addition of SDS leads to some changes in the binding process of hydrophobic probes to casein micelles. [Copyright &y& Elsevier]

Abstract: The influence of L-tryptophan (L-Trp) on the interphase electric properties of sodium dodecyl sulfate (SDS)/n-pentanol (n-C5H11OH)/water (H2O) system was studied by the method of AC impedance, and the distribution of L-Trp between the microemulsion phases with different structures in SDS/n-C5H11OH/H2O system was determined by UV–vis spectroscopy. The results show that L-Trp transfers from the lower phase (O/W or bicontinuous) to the upper phase (W/O), and that a small amount of SDS transfers from the upper phase to the lower phase correspondingly with the increase of the total SDS content at a constant weight ratio of n-C5H11OH/H2O=50/50 and a total L-Trp concentration of . In addition, the concentrations of L-Trp in both the upper and lower phases increase, but the SDS content decreases slightly in the upper phase and increases appreciably in the lower phase with the increase of the total L-Trp concentration at a constant total content of SDS. The interphase capacitance and the interphase charge-transfer current of the system increase, but the interphase resistivity decreases. [Copyright &y& Elsevier]

Abstract: The interactions of flavonoid, quercetin with sodium dodecyl sulfate (anionic surfactant) and cetyltrimethyl ammonium bromide (cationic surfactant) micelles were investigated. The average location site of quercetin in different micelles was determined by the cyclic voltammetry method with the aid of molecular optimization. The interaction parameters of quercetin with micelles of different charges such as binding constant K and normal binding energy ΔG were calculated. Furthermore, the morphologic change of the SDS and CTAB spherical micelles and rod-like micelles upon their interaction with quercetin was also observed. [Copyright &y& Elsevier]

Abstract: Electronic absorption spectra, fluorescence emission spectra, ATR-FTIR spectra, cyclic voltammetric measurements, and ab initio quantum calculation are used to study the properties of morin in CTAB micelles with different microstructures and microenvironments and to gain information about the binding of morin with CTAB micelles. Morin can be located in the CTAB micelle with its phenyl group (deviating with 38.98° from the planarity) only in the form of the monomer, which leads to increase of the planarity and extension of the π conjugation of the whole molecule. The embedding of two hydroxyl groups on the phenyl into a more hydrophobic microenvironment makes the oxidation peak of morin move to a higher potential with a decreased peak current. The binding of morin with CTAB micelles is a spontaneous () and endothermic process (), and the hydrophobic and electrostatic force is the main driving force for its solubilization. [Copyright &y& Elsevier]

[Display omitted] The cancer therapeutic efficacy of the peroxidase (POD)-mimicking nanozyme-based monotherapy is significantly hindered due to insufficient intratumoral hydrogen peroxide (H 2 O 2) and glutathione (GSH) consumption effect on reactive oxygen species (ROS). In this study, we present the development of poly (o -phenylenediamine)@gold nanoparticles (AuNPs) (PoPD@Au) nanocomposites for multifunctional catalytic-photothermal therapy. These nanocomposites exhibit triple distinct nanozymatic activities, i.e. , POD-like activity that catalyzes H 2 O 2 to ROS, glucose oxidase (GOx)-like activity that supplements endogenous H 2 O 2 , and GSH depleting activity that decreases the ROS consumption efficiency. This open source and reduce expenditure strategy for ROS generation allows for the amplification of tumor oxidative stress, thereby enhancing anti-tumor efficiency. Additionally, the PoPD@Au nanocomposites demonstrate outstanding photothermal conversion efficiency, contributing to the synergistic effect between PoPD and AuNPs. Moreover, we reveal the improved photothermal performance of PoPD@Au triggered by the tumor microenvironment pH, which provides additional benefits for targeted catalytic-photothermal therapy. This "four-in-one" design of PoPD@Au enables efficient anti-tumor effects both in vitro and in vivo , making it a universal strategy for engineering catalytic-photothermal therapeutic nanoagents. [ABSTRACT FROM AUTHOR]

[Display omitted] The key feature of living cells is multicompartmentalization for enzymatic reactions. Artificial cell-like multicompartments with micro domains are appealing to mimic the biological counterparts. In addition, establishing a sustainable, efficient, and controllable reaction system for enzymatic hydrolysis is imperative for the production of natural fatty acids from animal and plant-based fats. Reverse Janus emulsion microreactors, i.e. (W 1 + W 2)/O, is constructed through directly using natural fats as continuous phase and aqueous two-phase solutions (ATPS) as inner phases. Enzyme is confined in the compartmented aqueous droplets dominated by the salt of Na 2 SO 4 and polyethylene glycol (PEG). Enzyme catalyzed ester hydrolysis employed as a model reaction is performed under the conditions of agitation-free and mild temperature. Regulation of reaction kinetics is investigated by diverse droplet topology, composition of inner ATPS, and on-demand emulsification. Excellent enzymatic activity toward hydrolysis of plant and animal oils achieves 88.5 % conversion after 3 h. Compartmented micro domains contribute to condense and organize the enzymes spatially. Timely removal of the products away from reaction sites of oil/water interface "pushed" the reaction forward. Distribution and transfer of enzyme in two aqueous lobes provide extra freedom in the regulation of hydrolysis kinetics, with equilibrium conversion controlled freely from 14.5 % to 88.5 %. Reversible "open" and "shut" of hydrolysis is acheived by on-demand emulsification and spontaneous demulsification. This paper paves the way to advancing progress in compartmentalized emulsion as a sustainable and high-efficiency platform for biocatalytic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Understanding the structure-function relationships encoded on chiral catalysts is important for investigating the fundamental principles of catalytic enantioselectivity. Herein, the synthesis and self-assembly of naphthalene substituted bis - l / d -histidine amphiphiles (bis - l / d - NapHis) in DMF/water solution mixture is reported. The resulting supramolecular assemblies featuring well-defined P/M nanoribbons (NRs). With combination of the (P/M)-NR and metal ion catalytic centers (M n+ = Co2+, Cu2+, Fe3+), the (P)-NR-M n+ as chiral supramolecular catalysts show catalytic preference to 3,4-dihydroxy- S -phenylalanine (S -DOPA) oxidation while the (M)-NR-M n+ show enantioselective bias to R -DOPA oxidation. In contrast, their monomeric counterparts bis - l / d - NapHis-M n+ display an inverse and dramatically lower catalytic selectivity in the R/S -DOPA oxidation. Among them, the Co2+-coordinated supramolecular nanostructures show the highest catalytic efficiency and enantioselectivity (select factor up to 2.70), while the Fe3+-coordinated monomeric ones show nearly racemic products. Analysis of the kinetic results suggests that the synergistic effect between metal ions and the chiral supramolecular NRs can significantly regulate the enantioselective catalytic activity, while the metal ion-mediated monomeric bis - l / d - NapHis were less active. The studies on association constants and activation energies reveal the difference in catalytic efficiency and enantioselectivity resulting from the different energy barriers and binding affinities existed between the chiral molecular/supramolecular structures and R/S -DOPA enantiomers. This work clarifies the correlation between chiral molecular/supramolecular structures and enantioselective catalytic activity, shedding new light on the rational design of chiral catalysts with outstanding enantioselectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] Phototherapy, encompassing photothermal therapy and photodynamic therapy, is gaining attention as an appealing cancer treatment modality. To enhance its clinical implementation, a comprehensive exploration of the pivotal factors influencing phototherapy is warranted. In this study, the L/ d -cysteine (Cys)-copper ion (Cu2+) chiral nanoparticles, through the assembly of L/ d -Cys-Cu2+ coordination complexes, were constructed. We found that these nanoparticles interacted with chiral liposomes in a chirality-dependent manner, with d -Cys-Cu2+ nanoparticles exhibiting more than three times stronger binding affinity than l -Cys-Cu2+ nanoparticles. Furthermore, we demonstrated that the d -Cys-Cu2+ nanoparticles were more efficiently internalized by Hela cells in contrast with l -Cys-Cu2+. On this basis, indocyanine green (ICG), acting as both photothermal and photodynamic agent, was encapsulated into L/ d -Cys-Cu2+ nanoparticles. Experimental results showed that the l -Cys-Cu2+-ICG and d -Cys-Cu2+-ICG nanoparticles displayed almost identical photothermal performance and singlet oxygen (1O 2) generation capability in aqueous solution. However, upon laser irradiation, the d -Cys-Cu2+-ICG nanoparticles achieved enhanced anti-tumor effects compared to l -Cys-Cu2+-ICG due to their chirality-promoted higher cellular uptake efficiency. These findings highlight the crucial role of chirality in phototherapy and provide new perspectives for engineering cancer therapeutic agents. [ABSTRACT FROM AUTHOR]

[Display omitted] Degradation of polysaccharides based on lytic polysaccharide monooxygenases (LPMOs) has received considerably interest in the environment and energy fields since 2010. With the rapid development of nanozymes in various fields, it is highly desirable but challenging to develop LPMO-like nanozymes with high specificity and satisfied activity. Here, a defective copper-cobalt binuclear Prussian blue analogue (CuCoPBA) nanozyme was developed via a facile and ingenious methodology based on single histidine (His). For the first time, His-CuCoPBA nanozyme was found to exhibit LPMO-like activity with H 2 O 2 as a cosubstrate at room temperature and neutral pH, which can efficiently catalyze the degradation of galactomannans selectively. Significantly, the high degradation activity at pH 10 expands the application of Fenton-like nanozymes in alkaline condition. Singlet oxygen (1O 2), as a main reactive intermediate, plays a crucial role in the galactomannan degradation catalyzed by His-CuCoPBA nanozyme. Both control experimental and density functional theory (DFT) results indicate Cu - N x His contributes to the efficiently and selectively catalytic activity of His-CuCoPBA nanozymes by emulating the binding and catalytic sites of LPMOs. The present work not only represents a fundamental breakthrough toward degradation of polysaccharide based on nanozyme, but also contributes to understanding the catalytic mechanism of natural Cu-dependent LPMOs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A tunable confinement growth strategy is proposed to develop bimetallic oxides anode. • Well-defined ZnMn 2 O 4 nanoparticles are built to accommodate the volume variation. • DFT calculations reveal the synergetic effects between Mn and Zn atoms in ZnMn 2 O 4. • Optimal ZnMn 2 O 4 /C anode delivers significantly improved cycling stability. • Ex-situ X-ray absorption spectroscopy analysis identifies the delithiated Mn species. Spinel bimetallic transition metal oxide anode such as ZnMn 2 O 4 , has drawn increasing interest due to attractive bimetal interaction and high theoretical capacity. While it suffers from huge volume expansion and poor ionic/electronic conductivity. Nanosizing and carbon modification can alleviate these issues, while the optimal particle size within host is unclear yet. We here propose an in-situ confinement growth strategy to fabricate pomegranate-structured ZnMn 2 O 4 nanocomposite with calculated optimal particle size in mesoporous carbon host. Theoretical calculations reveal favorable interatomic interactions between the metal atoms. By the synergistic effects of structural merits and bimetal interaction, the optimal ZnMn 2 O 4 composite achieves greatly improved cycling stability (811 mAh g−1 at 0.2 A g−1 after 100 cycles), which can maintain its structural integrity upon cycling. X-ray absorption spectroscopy analysis further confirms delithiated Mn species (Mn 2 O 3 but little MnO). Briefly, this strategy brings new opportunity to ZnMn 2 O 4 anode, which could be adopted to other conversion/alloying-type electrodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Non-aqueous lamellar liquid crystal systems DBSA/MEA was constructed. • DBSA/MEA lamellar liquid crystal system has good lubrication and anti-corrosion properties. • Friction chemical reaction film and adsorption film improves the lubrication performance. • The coordination effect of MEA and Fe may be the key to improve corrosion resistance. Since lamellar liquid crystals (LLCS) could be used for lubrication, many LLCS systems have been constructed to improve lubrication performance. However, most studies focused on the LLCS of the water system, and its corrosiveness brought some limitations to its application. Therefore, it is necessary to construct a non-aqueous LLCS system with good lubrication and anti-corrosion properties to improve its applicability. Anionic surfactant dodecyl benzene sulfonic acid (DBSA) was used to construct non-aqueous LLCS in different solvents, including monoethanolamine (MEA) and diethanolamine (DEA). DBSA/H 2 O LLCS system was constructed for comparison. The LLCS was characterized by polarizing microscope (POM), small-angle X-ray scattering (SAXS), and rheology. Its microstructure was discussed. Meanwhile, we evaluated the lubrication and anti-corrosion performance of LLCS. Its lubrication mechanism was explained through tribology tests and X-ray photoelectron spectrometer (XPS) analysis of the wear scar surface. Its anti-corrosion mechanism was investigated by using the weightlessness method, electrochemical test method, and quantum chemical theoretical calculations. The DBSA/MEA non-aqueous LLCS system showed better lubrication performance than DBSA/DEA and DBSA/H 2 O LLCS. It can adsorb on the surface of the friction pair to form a lubrication friction film, which plays a better role in reducing friction and wear. The DBSA/MEA LLCS is less corrosive to metals because it can effectively isolate oxygen and water in the air between friction pairs. Furthermore, the lone pair electrons in the 2p orbital of the N atom in the MEA molecule could coordinate with the 3d empty orbital of the Fe atom, forming a protective film on the metal surface, which plays a good anti-corrosion effect. This work not only enriched the study of non-aqueous LLCS but also expanded its potential applications in the field of lubrication. [ABSTRACT FROM AUTHOR]

[Display omitted] Defects engineering has played an ever-increasing important role in electrochemistry, especially secondary lithium batteries. TiO 2 is regarded as a promising anode due to its attractive cycling stability, low volume strain and great abundance, while challenges of intrinsic poor electrical and ionic conductivity remain to be addressed. Herein, we report a three-in-one oxygen vacancy (V O)-involved pomegranate design for TiO 2- x /C composite anode, which provides highly improved electrical conduction, shortened Li+ pathway and promoted Li+ redox. N-doped mesoporous carbon acts as a robust scaffold to support the whole structure, electron highway and efficient reductant to generate V O on TiO 2 nanoparticles during crystallization. Theoretical calculations reveal the crucial role of surface V O on TiO 2 in Li electrochemistry. Resultantly, the optimal TiO 2- x /C anode achieves significantly enhanced cycling performance (203 mAh/g retained after 2000 cycles at 1 A/g). Postmortem analysis reveals the robustness of V O and reasonable structure stability upon cycles for improved battery performance. [ABSTRACT FROM AUTHOR]

[Display omitted] Tumor treatments based on phototherapy, such as photodynamic therapy (PDT) and photothermal therapy (PTT), are promising anticancer strategies. However, their dependence on light also poses several limitations for their application. Therefore, the establishment of a multifunctional nanotheranostic platform based on light therapy is needed to improve applicability of the technology. We designed yolk-shell magnetic Fe 3 O 4 @Carbon@Platinum-Chlorin e6 nanoparticles (MCPtCe6), which may be used for Magnetic resonance imaging (MRI) and synergistic catalytic-photodynamic-photothermal (catalytic-PDT-PTT) tumor therapy. We designed to compound multiple nanozymes and solve the drawbacks of single nanozyme and give additional functionalization to nanozymes for tumor therapy. Fe 3 O 4 has T2 weighted MRI ability. The designed yolk-shell structure can disperse Fe 3 O 4 in the carbon shell layer, which in turn can act as a carrier for PtNPs and improve the dispersion of both Fe 3 O 4 and Pt. Pt nanoparticles attached to the surface of N -doped carbon spheres enhanced the catalytic ability of the nanozyme to generate reactive oxygen species (ROS). The covalently linked photosensitizer chlorin e6 (Ce6) on the Fe 3 O 4 @C@Pt (MCPt) nanozyme is essential for the therapeutic effects of PDT. MCPtCe6 can be specifically activated by the microenvironment through an enzyme-like catalytic process and extend PDT/PTT in acidic and H 2 O 2 -rich microenvironments. The results showed that MCPtCe6 had a high photothermal conversion efficiency (η = 28.28%), indicating its feasibility for PTT. Further cellular and animal studies have revealed that catalytic-PDT-PTT therapy can effectively inhibit tumors both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: The emerging aqueous-based Cerberus emulsion droplets with multi-domains behave as an excellent platform to design cyto-mimetic compartmentalization for fabrication of anisotropic biomimetic materials and microreactors. However, the ultralow water/water interfacial tension impedes fabrication of aqueous Cerberus droplets in batch-scale and precisely topology regulation especially under lack of deep understanding of w/w interface properties. Experiments: Aqueous-based ternary phase diagram composed by salt, hydrophilic polymer and fluorocarbon compound is determined. Different emulsions employing the multiple aqueous solutions as internal phase and vegetable oil as continuous phase, are prepared by traditional vortex mixing based on the diagram. The construction mechanism of (W1 + W2 + W3)/O Cerberus droplets and relationship between droplet topology and the diagram are investigated. Findings: Diverse categories of aqueous-based emulsions from single emulsions, Janus emulsions, to Cerberus emulsions are delicately controlled in the same system based on the diagram. Various morphologies of Cerberus droplets such as linear and fan-like configurations are obtained, although spreading coefficient based on interfacial tension indicates preference of onion-like configuration. The viscosity plays an unexpected role in the construction of Cerberus droplets due to highly sensitive water/water interfaces within the droplets. Moreover, an empirical equation is perfectly applied, which endows quantitative prediction and control of lobe volume ratio within Cerberus droplets. [ABSTRACT FROM AUTHOR]

[Display omitted] • GNRs@Void@PPy yolk@shell nanostructures with tunable void space have been fabricated. • Synergistic enhancement of photothermal performance of GNRs@Void@PPy has been achieved. • The manipulation of the void space has offered GNRs@Void@PPy with high drug encapsulation efficiency. • The GNRs@Void@PPy holds great promise for tumor treatment through chemo-photothermal synergistic therapy. Synergistic therapy has been emerging as new trend for effective tumor treatment due to synchronous function and cooperative reinforcement of multi therapeutic modalities. Herein, gold nanorods (GNRs) encapsulated into polypyrrole (PPy) shell with tunable void space (GNRs@Void@PPy) showing yolk@shell nanostructures were innovatively designed. The exploitation of dual near-infrared (NIR) absorptive species offered synergistic enhancement of photothermal performance. In addition, the manipulation of the void space between them provided additional benefits of high drug encapsulation efficiency (92.6%) and, interestingly, tumor microenvironment and NIR irradiation triggered targeted drug releasing. Moreover, the GNRs@Void@PPy exhibited excellent biocompatibility, and optimal curative effect by chemo-photothermal synergistic therapy was achieved through both in vitro and in vivo antitumor activity investigation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Janus emulsions with a polymerizable monomer as inner oil phase were prepared. [•] The fundamentals of Janus emulsion formation were established. [•] The Janus topology of emulsion drops changes correspondingly with emulsion composition. [•] The size of Janus drops varied from hundreds to a few microns by adjusting stirring speed. [Copyright &y& Elsevier]

[Display omitted] • The PtFe-Fe 3 O 4 @N-C yolk@shell nanosphere was prepared. • The yolk@shell nanosphere exhibits enhanced catalytic activity. • The yolk@shell nanocatalyst was featured with high recyclability. Innovative design of nanocatalyst with high activity remains to be great challenge. Platinum (Pt) nanoparticle has already demonstrated to be excellent candidates in the field of catalysis. However, the scarcity and high price significantly hinder its large-scale production. In this work, dumbbell-like alloying nanoparticle of platinum-iron/ferroferric oxide (PtFe Fe 3 O 4) was prepared. On one hand, the design of the alloying nanoparticle can manipulate the d-band center of Pt, in further, the interaction with substrates. In addition, the dumbbell-like structured PtFe Fe 3 O 4 can offer heterogeneous interface, of which the interaction between PtFe and Fe 3 O 4 , supported by the X-ray photoelectron spectroscopic (XPS) results, leads to the enhanced catalytic efficiency. On the other hand, the introduction of Fe (iron) composition largely decreases the necessary amount of Pt, leading to efficient cost reduction. Moreover, to avoid the aggregation related activity attenuation problem, PtFe Fe 3 O 4 nanoparticle located in cavity of nitrogen heteroatom-doped carbon shell (PtFe Fe 3 O 4 @N C) as yolk@shell nanostructure was constructed and its improved catalytic performance was demonstrated towards the reactions of 4-nitrophenol (4-NP) reduction, β -ionone and benzhydrol oxidation. [ABSTRACT FROM AUTHOR]

Abstract: Drying condensed colloid suspension droplet on a horizontal glass substrate has been developed as a simple strategy to fabricate highly-ordered colloidal crystals. A uniform film obtained at above room temperature possessed a face-center-cubic (fcc) crystalline structure and excellent photonic properties. It was found that raising the drying temperature has resulted in a reduction in the lattice spacing of fcc colloidal crystals. The formation reason of uniform fcc colloidal crystals was directly related to the high drying temperature and the large colloid concentration. A ring-shaped stain generated by drying at room temperature has exhibited other highly-ordered microstructures with colloidal crystals, such as body center cubic (bcc) structure. [Copyright &y& Elsevier]

Abstract: The interaction between gelatin and sodium dodecyl sulfate (SDS) is investigated by calorimetry and photometric spectrum. The conformational change in gelatin chains upon binding of SDS, the morphology development of gelatin–SDS complex, and the nature of the interaction are studied by isothermal titration calorimetry (ITC), circular dichroism (CD), fluorescence, and freeze-fracture transmission electronic microscope micrograph (FF-TEM). The results show that the exothermic binding process is driven by both electrostatic and hydrophobic interaction. The triple helix structure of gelatin is decomposed to random coil upon the binding of SDS. The morphology of complex transfers from branch-like to “necklace-and-bead”. The interaction can be controlled by the concentration of SDS, the pH value of the solution, and the ionic strength of the system. [Copyright &y& Elsevier]

Abstract: Cyclodextrin (CD) modulated interactions between ionic surfactants with opposite charge and bovine serum albumin (BSA) at specific and nonspecific binding stages have been studied by isothermal titration calorimetry (ITC), fluorescence spectra and circular dichroism spectral measurements. At the specific binding stage with high affinity, the effectiveness of both α- and β-CD for hindering BSA–SDS interactions is quite weak; however, CD is more effective in hindering BSA–CTAB specific interactions. This is due to the cooperative electrostatic and hydrophobic interaction between BSA and SDS, and to the absence of the cooperative interaction between BSA and CTAB at the specific binding stage. For both BSA–SDS and BSA–CTAB systems (especially in the former system), α-CD is more effective in hindering BSA–surfactant interactions than β-CD. At the nonspecific binding stage, the addition of both α- and β-CD can hinder totally both BSA–SDS and BSA–CTAB hydrophobic interactions. This is caused by the more specific hydrophobic interaction between CD and surfactant compared with the hydrophobic interaction between BSA and surfactant. Our results show that the CD effect on the protein–surfactant interaction depends on both the nature of the protein–surfactant interaction and the complexing ability of CD with surfactant. [ABSTRACT FROM AUTHOR]

Abstract: The aggregation behavior of a mixed system consisting of a novel histidine-derived bolaamphiphile 1,12-dihistidine diaminododecane (H2D) and the conventional surfactant dodecyltrimethylammonium bromide (DTAB) has been investigated. The microstructure of the H2D/DTAB mixture has been identified by means of negative staining-TEM, dynamic light scattering (DLS), fluorescence spectra, FT-Raman spectroscopy, and differential scanning calorimetry (DSC). Rich morphologies are observed in the mixed system of H2D and DTAB over a relatively wide proportion range. At C DTAB/C H2D <12:1, vesicles are formed in the mixed system. At C DTAB/C H2D >12:1, vesicles and tube-like aggregates coexist, and more tube-like aggregates appear with further increase of C DTAB/C H2D. The formation mechanisms of the aggregation with various morphologies at different C DTAB/C H2D ratios are further deduced. [Copyright &y& Elsevier]

Abstract: In the present paper, we studied the interaction between n-dodecylammonium α-glutamate (GDA)/n-C5H11OH/H2O assemblies and methemoglobin by UV–vis spectroscopy, X-ray diffraction, electron spin resonance (ESR), rheology, and freeze-fractured transmission electron microscopy (FF-TEM). It is found that W/O microemulsion forms at a lower n-pentanol content and O/W microemulsion forms at a lower water content with the addition of methemoglobin. The existence of methemoglobin reduces the hexagonal liquid crystal region, while the lamellar liquid crystal region is little changed in the presence of methemoglobin. Moreover, methemoglobin and GDA/n-C5H11OH/H2O assemblies can affect their structures and properties and the change in behavior is dependent on the content of methemoglobin and the composition and structure of the GDA/n-C5H11OH/H2O system. The relationship among the changes in the structure and properties of GDA/n-C5H11OH/H2O assemblies, the content of methemoglobin, and the composition and structure of GDA/n-C5H11OH/H2O assemblies may provide some important theoretical information for elucidation of the interaction between methemoglobin and blood cell membrane and may also be helpful for the cure of some blood diseases. [Copyright &y& Elsevier]

Abstract: Photoisomerization of trans-stilbene (TS) was investigated in sodium dodecyl sulfate (SDS)/benzyl alcohol (BA)/H2O systems in order to establish the relationship between the reaction yields and the compositions and structures of molecular organized assemblies. The results show that, in SDS/BA/H2O systems with the structures of oil in water microemulsions, bicontinuous microemulsions, and hexagonal liquid crystals, the reaction yields are much larger than those in benzyl alcohol, both with and without the photosensitizer 9,10-anthracenedicarbonitrile. However, SDS/BA/H2O water in oil microemulsion and lamellar liquid crystal can obviously catalyze the photoisomerization of TS only when the photosensitizer is not present. The yield is increased with the increase in H2O content or with the decrease in BA content. [Copyright &y& Elsevier]

[Display omitted] • FeP, N -Carbon and Fe, P, N -Carbon hollow nanospheres were prepared. • Fe, P, N -Carbon showed the onset potential of 1.03 V and half wave potential of 0.89 V when used as ORR electrocatalysts. • The ORR performance of Fe, P, N -Carbon was better than that of FeP, N -Carbon. • The unique nanostructure and favorable chemical components contributed to excellent ORR performance. In recent years, carbon materials co-doped with transition metals and heteroatoms have been widely used in the oxygen reduction reaction (ORR) as an alternative to platinum/carbon catalysts because of their high efficiency, low price, and appropriate sustainability. Herein, we report the synthesis of FeP, N -doped carbon (FeP, N -Carbon) hollow nanospheres (HNSs) and Fe, P, N -doped carbon (Fe, P, N -Carbon) HNSs. The FeP, N -Carbon was obtained via the pyrolysis of poly(o -phenylenediamine) (PoPD) HNSs in the presence of Fe(NO 3) 3 and phytic acid (PA), whereas Fe, P, N -Carbon was obtained by first pyrolyzing PoPD HNSs with Fe(NO 3) 3 , followed by another cycle of pyrolysis with PA. Fe, P, N -Carbon exhibited a better ORR performance than FeP, N -Carbon, with an onset potential of 1.03 V, a half-wave potential of 0.89 V and a limiting current density of 5.75 mA cm−2. The findings will provide insights into the controlled synthesis of transition-metal-heteroatom-codoped carbon nanomaterials for the development of advanced ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: Taking advantage of photoinduced electron transfer, one dimensional organic nanomaterials with tunable donor-acceptor (D-A) interface provide a promising avenue to get high optoelectric properties. However, strong charge transfer interaction between D and A segments impedes the formation of long-range ordered structure, which limits the charge transport through efficient π electronic delocalization. Incorporation of chiral peptide offering various hydrogen bonding (H-bonding) along with asymmetric molecular structure enables substantially controllable D-A interface and tunable organization of the π -conjugates. Experiments: A new amphiphilic perylene diimide (CUPDI) with PDI as an acceptor is designed and synthesized. A polar chiral dipeptide composed of β -alanine and l -histidine with the imidazole ring as the donor i.e. , l -carnosine, is incorporated at one of imides. Transition of various supramolecular assemblies of CUPDI is realized by changing CUPDI concentration and solvents. The photoelectronic properties of the assemblies are investigated as well as their association with the microstructure of the nanomaterials. Findings: Delicately tuned hydrogen bonds between the peptides and π - π interaction between PDI cores in different solvents enable the formation of assemblies with multifarious microstructures such as small spherical aggregates, nanowires with uniform diameter, nanobelts, and irregular aggregates. The maximum amount of photocurrent enhancement is up to 1.08 µA observed for the nanobelt, four times higher than that of irregular aggregates. However, the nanowires show the best performance of 7.1-fold in response to ammonia. Thus, the photoelectric performances are strongly dependent on the the molecular arrangement within the nanomaterials. [ABSTRACT FROM AUTHOR]

[Display omitted] Recently, nanozymes have attracted sustained attention for facilitating next generation of artificial enzymatic cascade systems (ECSs). However, the fabrication of integrated multi-ECSs based on a single nanozyme remains a great challenge. Here, inspired by the biological function and self-assembling ability of arginine (R), we synthesized arginine-rich peptide-Pt nanoparticle cluster (ARP-PtNC) nanozymes that mimic two typical enzymatic cascade systems of uricase/catalase and superoxide dismutase/catalase in natural peroxisome. ARPs containing at least 10 arginine residues contribute to the cluster formation based on hydrogen bonding and coordination. The well-designed peptide-Pt hybrid nanozyme not only possesses excellent uricase-mimicking activity to degrade uric acid effectively, but also serves as a desired scavenger for reactive oxygen species (ROS) harnessing two efficient enzyme cascade catalysis of uricase/catalase and superoxide dismutase/catalase. The surface microenvironment of the hybrid nanozymes provided by arginine-rich peptides and the cluster structure contribute to the efficient multiply enzyme-like activities. Fascinatingly, the hybrid nanozyme can inhibit the formation of monosodium urate monohydrate effectively based on the architecture of ARP-PtNCs. Thus, ARP-PtNC nanozyme has the potential in gout and hyperuricemia therapy. Rational design of ingenious peptide-metal hybrid nanozyme with unique physicochemical surface properties provides a versatile and designed strategy to fabricate multi-enzymatic cascade systems, which opens new avenues to broaden the application of nanozymes in practice. [ABSTRACT FROM AUTHOR]

Reverse Janus emulsion, with droplets composed by "two rooms" of water phases, is a novel multiple emulsion attributed to excellent integration capability and biocompatibility. However, significant instability compared with normal Janus emulsions renders the stability issue of great importance. Moreover, the ultra-low aqueous-aqueous inner interfacial tension, the anisotropic nature of the droplets with distinct lobe composition, and the random orientation in the continuous phase endow the complicated and various demulsification mechanisms. Reverse Janus emulsion of (W 1 +W 2)/O, employing typical salt-alcohol aqueous two-phase system (ATPS) as inner phases, is prepared in batch scale by conventional one-step vortex mixing. The demulsification process is detected by multiple light scattering technique, which provides real-time, in-situ, and quantitative information of emulsion evolution. Moreover, the fusion pattern of the anisotropic droplets is illustrated by the combination with light microscopy and size distribution measurement. Coalescence and sedimentation are found to be two main demulsification processes. Two salt "body" lobes of the "snowman" shaped Janus droplets combine first resulting in an intermediate Cerberus topology with two alcohol "heads" on one salt "body". Subsequently, two "head" lobes coalesce resulting in a larger Janus droplet. Ultimately, the Gibbs free energy leads to a final state with three separated liquids. In addition, the variation in lobe viscosity, density, and properties of interfacial film greatly affect the demulsification rate and fusion pattern. A critical alcohol/surfactant mass ratio of 2 is found, beyond which a completely different fusion pattern occurs. Two alcohol "body" lobes combine first resulting in an intermediate Cerberus topology with two salt "heads" on one alcohol "body". Subsequently, two "head" lobes coalesce resulting in a larger Janus droplet. The findings are instructive in the stability of aqueous based multiple emulsions with advanced morphologies and meanwhile, promote the future application of this novel emulsion in food science, pharmacy, and biomimetic compartmentalization. [ABSTRACT FROM AUTHOR]

TiO 2 nanosheet/NiO nanorod heterojunction hybrids have been developed through a hydrothermal route, where NiO nanorods (size: 5 nm in diameter and 20–40 nm in length) are deposited at the {0 0 1} facet of anatase TiO 2 nanosheets. The photocatalysts were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), N 2 adsorption-desorption analysis, UV–vis spectroscopy, X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy and time-resolved fluorescence. The TiO 2 /NiO photocatalysts exhibited good photocatalytic activities towards the degradation of methyl blue (MB) and phenol, and hydrogen generation efficiency under visible light irradiation. The maximum rate constant can be reached 0.0279 min−1 and 0.0135 min−1 respectively, which are about 12 and 10 times higher than that of TiO 2 nanosheets. And the hydrogen generation efficiency is 10 times higher than physical mixing of TiO 2 and NiO. Photocatalytic degradation efficiency remains more than 90% after 6 times cycle dye degradation, and the H 2 production efficiency is almost the same after four cycles, suggesting good stability and reusability. The enhanced photocatalytic activities are associated with the rational design of TiO 2 /NiO hierarchical heterojunctions which ensues high photogenerated charge separation efficiency. With the improved photocatalytic performance, the TiO 2 /NiO heterojunction hybrids are expected to be potential photocatalysts in environmental and energy related areas. [ABSTRACT FROM AUTHOR]

Developing nonprecious electrocatalysts for efficient oxygen reduction reaction (ORR) have aroused increasing interest recently. Herein, α-MnO 2 nanosheet-based hollow spheres encapsulated by N-doped carbon (denoted as N-Carbon/MnO 2 /N-Carbon) as efficient ORR electrocatalysts were reported. As started from redox reactive polystyrene/polyaniline (PS/PANI) core/shell templates, MnO 2 and PANI layers were sequentially in situ loaded, leading to the formation of MnO 2 nanosheet-based hollow spheres encapsulated by PANI (denoted as PANI/MnO 2 /PANI) after PS removal process. Finally, the calcination process ensured the crystallization of MnO 2 and carbonization of PANI, resulting in the formation of N-Carbon/MnO 2 /N-Carbon hybrid shells. The N-Carbon/MnO 2 /N-Carbon hybrid shells showed excellent electrocatalytic activity towards ORR in 0.1 mol L −1 KOH aqueous solution, making the hybrids promising cathode catalysts for alkaline fuel cell applications. [ABSTRACT FROM AUTHOR]

The applications of ionic liquids (ILs)/lamellar liquid crystals (LLCs) have great potential in nanotribology because they could be used where conventional oils could not work. To clarify the lubricating mechanism, herein, ILs/LLCs lubricants were prepared by addition of amphiphilic 1-alkyl-3-methylimidazolium hexafluorophosphate (C n mimPF 6 , n = 8, 12) into TritonX-100/n-C 10 H 21 OH/H 2 O LLCs with different concentration. The influence of alkyl chain lengths of ILs on the microstructures and the tribological properties of LLCs were investigated. The phase structure parameters and the tribological properties of the LLCs in the presence of C n mimPF 6 were analyzed via freeze-fracture transmission electron microscopy (FF-TEM), the small-angle X-ray scattering (SAXS) technique, oscillating reciprocating friction and wear tester. Compared with the LLCs without C n mimPF 6 , 4.5 wt% C n mimPF 6 /LLCs can reduce the friction and wear of sliding pairs. The better lubricating property and antiwear capability of the C n mimPF 6 /LLCs may be attributed to the increasing of the interlayer thickness d and the decreasing of the bilayer thickness d 0 in microstructures. This work provides a better understanding of the relationship between the microstructures and friction wear performances of ILs/LLCs. [ABSTRACT FROM AUTHOR]

A facile hydrothermal process is developed for the synthesis of NiCo 2 S 4 /reduced graphene oxide (RGO) hybrid and NiCo 2 S 4 hollow spheres. The morphology and microstructure are characterized by powder X-ray diffraction (XRD), Raman spectra, transmission electron microscopy (TEM), high-resolution TEM (HRTEM), selected area electron diffraction (SAED), and energy dispersive spectrometry (EDS) mapping. NiCo 2 S 4 nanoparticles with the diameter of about 20–30 nm were in-situ grown on RGO sheets. NiCo 2 S 4 hollow spheres were obtained with the diameter of about 300–400 nm and the width of shell in the range of 30–40 nm in the absence of graphene oxide (GO). GO as a substrate material can offer abundant active sites for nucleation of NiCo 2 S 4 and can be reduced to RGO, providing excellent electron transfer path and high conduction, which enable the fast surface redox reaction. Supercapacitor based on NiCo 2 S 4 /RGO hybrid shows a high specific capacitance of 1804.7 F/g at a current density of 0.5 A/g. Due to the high capacitive performance of NiCo 2 S 4 /RGO hybrid, the NiCo 2 S 4 /RGO//AC asymmetric supercapacitor (ASC) possesses an extended voltage window of 1.5 V, high energy density of 24.4 W h/kg at a power density of 750 W/kg in 2 mol/L KOH electrolyte. NiCo 2 S 4 /RGO hybrid can serve as a promising electrode material for high performance supercapacitors. [ABSTRACT FROM AUTHOR]

Abstract: The self-assembly behavior of mixed systems consisting of amphiphilic chitosan derivatives C n -OCMCS (n =4, 6, 8) and the conventional cationic surfactant cetyltrimethylammonium bromide (CTAB) is investigated. Transmission electron microscopy (TEM), dynamic light scattering (DLS), small-angle X-ray diffraction (XRD), UV–vis spectra, and zeta potential measurements have been utilized to characterize the microstructures of C n -OCMCS/CTAB mixtures in aqueous solutions. Spherical vesicles are formed spontaneously in the C n -OCMCS (n =4, 6, 8)/CTAB mixed systems, and the increased hydrophobic chain length of C n -OCMCS enhances the ability to form vesicles. The addition of NaBr with higher concentrations to the vesicle system transforms vesicles into micelles, and an increase in temperature decreases the vesicle size. The results indicate that the main driving forces controlling vesicle formation may be attributed to the strong electrostatic interactions as well as the hydrophobic interactions, and also the hydrogen bonding between C n -OCMCS molecules. [Copyright &y& Elsevier]

Abstract: The adsorption behavior of thionine on gold nanoparticles of two different mean diameters, 18 and 5 nm, was compared by using UV–vis spectroscopy, fluorescence spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and quantum chemical calculations. It is found that the addition of small particles makes the monomer peak of thionine finally disappear, and the corresponding dimer peak is significantly increased. Small gold nanoparticles make the equilibrium between the monomer and H-type dimer forms of thionine move largely toward the dimer forms. Due to the stronger binding between thionine and small gold nanoparticles, the fluorescence quenching of thionine by small particles is enhanced compared to large particles, and the quenching is both static and dynamic. TEM images indicate that the addition of thionine results in a heavy clustering for small particles, and the resulting thionine–gold nanoclusters of about 45 nm were obtained. Quantum chemical calculations, which were based on the density functional theory (DFT) at the B3LYP level, and infrared spectroscopic studies show that the nitrogen atoms of the NH2 moieties of thionine bind to the gold nanoparticle surfaces. For 18 and 5 nm particles, the surface-to-volume atomic ratios are about 0.0597 and 0.2148, respectively. The higher surface-to-volume atomic ratio and the higher surface free energy result in stronger binding of thionine on small particle surfaces, which can be used to modulate the arrangement of dye molecules on particle surfaces, and thus control the properties of organic–inorganic nanocomposite materials. [Copyright &y& Elsevier]

Abstract: Vesicles have many important applications in many different fields. In the present paper, we report for the first time that oligonucleotide can induce single-chained cationic surfactant molecules to aggregate into vesicles by determining turbidity with a Uv–vis spectrophotometer, observing images with a transmission electron microscope and/or fluorescence microscope, and dynamic light scattering. This study may increase the efficiency and applicability for a DNA/amphiphile system. [Copyright &y& Elsevier]

Abstract: The abnormal structure conversion of CaCO3 from calcite to aragonite was investigated with a mixture of polyacrylamide (PAM) and cetyltrimethylammonium bromide (CTAB) as additives by a hydrothermal method. A novel morphology of aragonite, “magnified” cubic shape, was observed. In order to investigate the effects of PAM and experimental temperature on the morphology and phase of CaCO3, the samples were synthesized without any additives and with PAM as template at 90 and 120 °C, respectively. The results indicate that both the interaction between the mixed template and the CaCO3 and the elevated experiment temperature play important roles in the process of polymorph transformation. [Copyright &y& Elsevier]

This paper describes the morphological characterization of aqueous dispersions of PC amphiphiles and bolaamphiphile AEC by microscopy, the liposomal membrane fluidity, and the zeta potential. Results indicate that the bolaamphiphile AEC can be included within conventional egg–PC liposome bilayers. This behavior could be due to their preference for the stretched conformation within the PC membranes. [Copyright &y& Elsevier]