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Hypothesis Newtonian liquids, usually used as base oil lubricants, exhibit low viscosity under extreme thermal conditions, needed for the functioning of wind turbines. This is directly affecting the colloidal stability and the tribological properties of the formulations containing additives, such as MoS2. Here, it was hypothesized that the surface hydrophobization of MoS2 particles will allow for an increased colloidal stability of the resulting formulations, for temperatures as high as 80 °C. Experiments The antifriction properties and the thermal stability of the designed formulations were determined on submicron MoS2 particles dispersed in poly-α-olefins (PAO) base oils of different dynamic viscosities (from 32 to 1650 mPa·s at 25 °C). The submicron particles of MoS2 (300–500 nm in diameter) were synthesised by a simple one-pot solvothermal method under mild conditions. The resulting particles were hydrophobized in situ in PAO base oils using alkyltrichlorosilane grafting agents with two chain lengths (C8 and C18). Findings The covalent grafting of alkylsilanes through Mo-O-Si bonds was confirmed by DFT calculations and FT-IR measurements. Turbiscan optical analysis revealed that thermal and colloidal stabilities can be significantly improved depending on oil viscosity and chain length of the grafting agent. The formulations in the PAO65 oil remained highly stable (TSI

Curcumin is a natural compound extracted from turmeric (Curcuma longa), which has shown remarkable anti-inflammatory, antibacterial, and possibly anticancer properties. The intense absorption in the visible domain and the possibility of intersystem crossing make curcumin attractive also for photodynamic therapy purposes. In the present contribution, we unravel, thanks to non-adiabatic surface hopping dynamics, the interplay between intersystem crossing and hydrogen transfer in the enol form, i.e. the most stable tautomer of curcumin. Most notably, we show that while hydrogen transfer is ultrafast and happens in the sub-ps regime, intersystem crossing is still present, as shown by the non-negligible population of the triplet state manifold after 2 ps. Hence, while the hydrogen transfer channel can act as a deactivating channel, curcumin, also in the red-shifted absorption enol form, can still be regarded as potentially favorable for photodynamic therapy applications.

Curcumin is a natural compound extracted from turmeric (curcuma longa), which has shown remarkable antiinflammatory, antibacterial, and possibly anticancert properties. The intense absorption in the visible domain, and the possibility of intersystem crossing make curcumin attractive also for photodynamic therapy purposes. In the present contribution we unravel, thanks to non-adiabatic state hopping dynamics, the competition between intersystem crossing and hydrogen transfer within enol, the most stable tautomer of curcumin. Most notably, we show that while hydrogen-transfer is ultrafast and happens in the sub-ps regime, intersystem crossing is still present, as shown by the non-negligible population of the triplet state manifold after 2 ps. Hence, while the hydrogen transfer channel can act as an unfavorable deactivating channel, curcumin, also in the red-shifted absorption enol form, can still be regarded as potentially favorable for photodynamic therapy applications.

International audience; Cyclocurcumin is a turmeric component that attracted much less attention compared to the well known curcumin. In spite of the less deep charcaterization of its properties, cyclocurcumin has shown promising anticancer effects when used in combination with curcumin. Especially, due to its peculiar molecular structure, cyclocurcumin can be regarded as an almost ideal photoswitch, whose capabilities can also be exploited for relevant biological applications. Here, by means of state-of-the-art computational methods for electronic excited-state calculations (TD-DFT, MS-CASPT2, XMS-CASPT2) we analyze in detail the absorption and photoisomerization pathways leading from the more stable trans isomer to the cis one. The different molecular surroundings, taken into account by means of electrostatic solvent effect and compared with available experimental data, have been found to be critical in describing the fate of irradiated cyclocurcumin: while in non-polar environments an excited state barrier prevents photoisomerization and favours fluorescence, in polar solvents an almost barrierless path results in a strikingly decrease of fluorescence, opening the way toward a crossing region with the ground state and thus funneling the photoproduction of the cis isomer.

The upgrading of lignin-derived bio-oils involves a HydroDeOxygenation (HDO) reaction through either the Hydrogenation (Hyd) or the Direct DeOxygenation (DDO) route, the latter limiting hydrogen consumption. Herein, dispersion-corrected DFT has been used to evaluate the adsorption behavior of phenol (as a representative model of bio-oils) and two by-products (water and CO) over various crystalline and amorphous silica surfaces to evaluate their potential selectivity (DDO/Hyd) and efficiency (low inhibiting effect) for HDO processing. Phenol can adsorb through three modes, flat π-interaction, flat O-interaction or perpendicular O-interaction. All crystalline surfaces show a preference for the flat π-interaction, which is expected to promote the Hyd route. Over amorphous surfaces the flat O-interaction dominates, and a very specific and strong interaction (around −120 kJ/mol) was found on SiO2-3.3 and SiO2-2.0 surfaces where the phenol molecule loses its aromaticity, which is very promising for its degradation under catalytic conditions. In addition, this makes those surfaces very efficient to adsorb selectively phenol in presence of water and CO. Remarkably, on all silica surfaces, the interaction energy of CO is nearly negligible, which makes them more attractive for HDO process compared to sulfide catalysts with respect to the inhibiting effect criteria.

International audience; The use of MoS ⁠ 2 nanoparticles as additive to lubricating oils is restricted by their low stability in oily media, which limits their use despite the enormous benefits associated with their intrinsic properties in terms of reduction of friction and wear coefficients. In this context, we investigated the effect of morphologies (platelets vs spheres) and surface functionalization of nanoparticles on the stability of their suspensions in poly-α-olefins (PAO) with various viscosities, which are base oils used in wind turbines. The particles were characterized by XRD, FTIR, scanning electron microscopy, atomic force microscopy and dynamic light scattering, and the stability of the resultant formulations was followed by optical (non-contact) measurements. It was found that the dispersions had similar stability despite the larger size of platelet-like particles compared to spherical ones (1-5 μm vs 600-800 nm). The dispersibility could be increased through grafting of alkylsilane on the surface defects (the longer the alkyl chain, the more stable the formulation) and with the increase of the oil kinematic viscosity (from 34 to 1705 cps at 25 °C).

Hollow carbon spheres (HCSs) were prepared from sugar alcohols encapsulated in UV-cured polymer which were hydrothermally treated in solutions of carbon precursors and carbonised at different temperatures in the presence or absence of graphitisation catalysts (Fe(III) and Ni(II)). The resultant HCSs were then spread at the surface of salt water and submitted to a solar simulator in a special ventilated chamber. The presence of HCSs floating at the surface of water was shown to increase significantly the evaporation rate compared to an HCS-free reference. The effect of carbon precursor, pyrolysis temperature, size and presence of metal was investigated and discussed. The best performances were obtained with nickel-loaded HCSs treated at 1500 °C, leading to a water evaporation rate increased by 70% with respect to the reference. These performances were discussed in terms of floatability, the latter being related to wettability, composition and apparent density of the HCSs. A model was developed for separating the contributions of floatability and thermal conductivity, definitely demonstrating that the former was the key parameter explaining the performances of floating HCSs for evaporating water submitted to a radiant heat flow.

International audience; Wind energy has become one of the most viable green and sustainable energy sources. A major concern of this sector is the damage of mechanical components and energy losses caused by repeated friction and wear, which lead to reduced efficiency and increased maintenance costs. The development of new lubricant additives with high anti-wear properties and friction reduction capabilities is of paramount importance to ensure long service life and high efficiency of mechanical devices. Herein, flower-shaped MoS2 nano-additives of about 150 nm were prepared under mild conditions through a hydrothermal process. Octyl- and octadecyltrichlorosilane were used as surface hydrophobization agents to enhance the colloidal stability of MoS2 nano-additives formulations in wind turbine engine oil. Increasing the length of the alkyl chain grafted onto the particles improved the colloidal stability up to at least one year and, more importantly, resulted in the lowest friction and best wear reduction capabilities, as shown by the pin-on-disk tribometer and laboratory wear tests

Cyclocurcumin, a turmeric curcuminoid with potential therapeutic properties, is also a natural photoswitch that may undergo E/Z photoisomerization under UV light. In order to be further exploited in relevant biological applications, photoactivation under near infrared (NIR) irradiation is required. Such requirement can be met through opportune chemical modifications,and most notably by favoring two-photon absorption (TPA) probability. Herein, a general and efficient synthesis of a biomimetic 2,6-g-pyrone analogue of cyclocurcumin is described, motivated by the fact that molecular modeling previews an order of magnitude increase of the NIR TPA cross-section for the latter compared to the natural counterpart. Three retrosynthetic pathways have been identified (i) via an aryl-oxazole intermediate or via an aryl-diynone through (ii) a bottom-up or (iii) a top-down approach. While avoiding the passage through unstable synthons or low yield intermediate reactions, only the latest approach could conveniently afford the 2,6-g-pyrone analogue of cyclocurcumin, in ten steps and with an overall yield of 18%. The photophysical properties of our biomimetic analogue have also been characterized showing an improved photo-isomerization yield over the parent natural compound. The potentially improved non-linear optical properties, as well an enhanced stability, may be correlated to the enforcement of the planarity of the pyrone moiety leading to a quadrupolar D-p-A-p-D system.

Cyclocurcumin is a natural compound extracted from turmeric and showing, in addition to antiinfective, antibacterial, and intinflammatory capabilities, solvent-dependent phtoswitching ability. The solvent-dependent photochemistry of cyclocurcumin has been rationalized on the basis of a competition between π-π* and n-π* states. Recently we have reported the synthesis of a biomimetic analogue showing enhanced photochemical properties and in particular presenting photoswitching capacity in various media. In the present contribution we rely on the use of molecular modeling and simulation, incuding density functional and wavefunction based methods to explore the excited states potential energy surface landscape. We see that the addition of a carbon-carbon double bond to the core of the natural compounds favors the population of the π-π* state, whatever the choice of the solvent, and hence leads to photoisomerisation, with fluorescence reduced to only a minor channel, rationalizing the experimental observations. In addition, the two photon absorption cross section is also strongly increased compared to the parent compound, paving the way to the use in biologically oriented applications.

Cyclocurcumin, a turmeric curcuminoid with potential therapeutic properties, is also a natural photoswitch that may undergo E/Z photoisomerization under UV light. In order to be further exploited in relevant biological applications, photoactivation under near infrared (NIR) irradiation is required. Such requirement can be met through opportune chemical modifications,and most notably by favoring two-photon absorption (TPA) probability. Herein, a general and efficient synthesis of a biomimetic 2,6-g-pyrone analogue of cyclocurcumin is described, motivated by the fact that molecular modeling previews an order of magnitude increase of the NIR TPA cross-section for the latter compared to the natural counterpart. Three retrosynthetic pathways have been identified (i) via an aryl-oxazole intermediate or via an aryl-diynone through (ii) a bottom-up or (iii) a top-down approach. While avoiding the passage through unstable synthons or low yield intermediate reactions, only the latest approach could conveniently afford the 2,6-g-pyrone analogue of cyclocurcumin, in ten steps and with an overall yield of 18%. The photophysical properties of our biomimetic analogue have also been characterized showing an improved photo-isomerization yield over the parent natural compound. The potentially improved non-linear optical properties, as well an enhanced stability, may be correlated to the enforcement of the planarity of the pyrone moiety leading to a quadrupolar D-p-A-p-D system.

Cyclocurcumin is a natural compound extracted from turmeric and showing, in addition to antiinfective, antibacterial, and intinflammatory capabilities, solvent-dependent phtoswitching ability. The solvent-dependent photochemistry of cyclocurcumin has been rationalized on the basis of a competition between π-π* and n-π* states. Recently we have reported the synthesis of a biomimetic analogous showing enhanced photochemical properties and in particular presenting photoswitching capacity in various media. In the present contribution we rely on the use of molecular modeling and simulation, incuding density functional and wavefunction based methods to explore the excited states potential energy surface landscape. We see that the addition of a carbon-carbon double bond to the core of the natural compounds favors the population of the π-π* state, whatever the choice of the solvent, and hence leads to photoisomerisation, with fluorescence reduced to only a minor channel, rationalizing the experimental observations. In addition, the two photon absorption cross section is also strongly increased compared to the parent compound, paving the way to the use in biologically oriented applications.

Cyclocurcumin is a natural compound extracted from turmeric and showing an interestingsolvent-dependent photoswitching ability. The solvent-dependent photochemistry ofcyclocurcumin has been rationalized on the basis of a competition between -* and n-*states.1 Furthermore, we have reported the synthesis of a biomimetic analogue showingenhanced photochemical properties and in particular presenting photoswitching capacity invarious media.2 In addition, molecular modeling and simulation, including density functionaland wavefunction based methods were used to explore the excited states potential energysurface landscape. We realize that with cyclocurcumin, the addition of a carbon-carbondouble bond to the core of the natural compound favors the population of the -* state,whatever the choice of the solvent, and hence leads to photoisomerization, with fluorescencereduced to only a minor channel comparing with natural derivative.3 In addition, the two-photon absorption (TPA) cross section is also strongly increased compared to the parentcompound, paving the way to the use in biologically oriented applications. Apart of that, weare also interested in the interaction between these systems and lipidic membranes as apotential photocontrolled way to destabilize it, which can yield in cellular apoptosis or vesicledrug delivery. Likewise, natural curcumin was studied as a potential photodynamic therapycandidate taking advantage of it larger TPA comparing with other used drugs.

Lactobacillus rhamnosus GG (LGG) was encapsulated in core–shell alginate–silica microcapsules by coating the electrosprayed ionogel with a silica shell via hydrolysis/condensation of alkoxysilane precursors. The viability of encapsulated LGG highly depends on the mineralisation conditions (in aqueous or organic phases), identified as a critical step. More importantly, due to the unswelling of silica and to its mesoporosity that allows nutriment-metabolite diffusion, it was possible to avoid cell leakage and additionally insure bacterial growth inside the microcapsules. The results of this work gave a proof-of-concept for controlled bacterial proliferation in microcompartments, which have straightforward applications in oral delivery of probiotics.

The catalytic hydrodeoxygenation (HDO) of lignin is an important route to produce green aromatics. Herein we study the adsorption of key phenolic molecules (phenol, catechol, guaiacol, anisole) over various metallic nanoparticles (NP) (Ni, Cu, Co, Fe) supported over amorphous silica, by the periodic spin polarized density functional theory (DFT). CO and water are potential inhibiting molecules present in the lignin pyrolysis gas. Therefore their competing adsorption is also studied in details. Our calculations show that the oxygenated compounds have a stronger interaction at the interface between the NP cluster and the silica for all the studied metals. By comparing the resulting adsorption energies, we found that the Ni13@silica catalyst is the most attractive one for oxygenated molecules. The most stable configuration is a phenol adsorption at the interface through the OH group with the silica surface and the aromatic ring with the transition metal cluster. In addition, we show that the adsorption of the oxygenated compounds is not impacted by the presence of inhibiting molecules on Fe13@silica, Co13@silica and Ni13@silica catalysts. This type of DFT investigation appears to be useful to suggest suitable formulations for an optimal HDO of lignin.

According to the US Food and Drug Administration and the European Food Safety Authority, amorphous forms of silica and silicates are generally recognized to be safe as oral delivery ingredients in amounts up to 1500mg per day. Silica is used in the formulation of solid dosage forms, e.g. tablets, as glidant or lubricant. The synthesis of silica-based materials depends on the payload nature, drug, macromolecule or cell, and on the target release (active or passive). In the literature, most of the examples deal with the encapsulation of drugs in mesoporous silica nanoparticles. Still to date limited reports concerning the delivery of encapsulated macromolecules and cells have been reported in the field of oral delivery, despite the multiple promising examples demonstrating the compatibility of the sol-gel route with biological entities, likewise the interest of silica as an oral carrier. Silica diatoms appear as an elegant, cost-effective and promising alternative to synthetic sol-gel-based materials. This review reports the latest advances silica-based systems and discusses the potential benefits and drawbacks of using silica for oral delivery of drugs, macromolecules or cells.

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The elaboration of new hybrid polymer/metal composite materials depends on the development of innovative polymer matrices with improved mechanical properties and high effective adhesion behaviour with metal surfaces. This way, a new type of polyolefin was developed based on a peculiar crosslinking reaction. For this elaboration, an iPP-g-MAH with 1 wt% of MAH was crosslinked with polyether triamine molecules by twin screw reactive extrusion. The evolution of the crosslinking reaction, the microstructure and the mechanical behaviour of the different materials were studied as a function of the NH2:MAH molar ratio in the range of 0:1 and 1.5:1. Gel content determination and FTIR analysis were performed to characterise the material at the molecular scale, when differential scanning calorimetry, wide angle X-rays scattering and self-successive auto-nucleation techniques were used for a deep microstructure analysis. Brillouin spectroscopy showed an interesting evolution of the elastic constants at the microscopic scale and results were in good agreement with those obtained at the macroscopic scale by a video-controlled uniaxial tensile test. Moreover, it was demonstrated that the true mechanical behaviours switch from brittle to ductile illustrating an important improvement of the resilience ability of the synthetized materials as a function of the NH2:MAH molar ratio even for molar ratio other than an equimolar ratio, with remaining MAH or NH2 chemical groups for further chemical reaction.

Immobilization of beta-galactosidase (beta-gal) into porous materials might afford to supported biocatalysts for the hydrolysis of diary products or to food additives for lactose intolerant people. Activity and stability of the loaded material generally depend on the interactions between the enzyme and the support, as well as on the pore size. Herein, Raman spectroscopy was used to evaluate the specific adsorption the enzyme into meso-macroporous silica materials, containing interconnected mesopores of 9 nm and macropores of 200 nm. Non-porous silica was used as reference material to determine the Raman fingerprint of physisorbed enzyme in the absence of any confinement. While the beta-gal physisorbed on the surface of non-porous silica material exhibits the same Raman spectra as the free enzyme, the enzyme physisorbed onto meso-macroporous materials show frequency displacements of characteristic amide groups as a function of initial concentration of the feed enzymatic solution. In fact, at low initial concentration in enzyme, no shifts of the amides were recorded on Raman spectra as compared with free enzyme, indicating a preferential physisorption into macropores. By increasing the enzyme concentration, the frequency of Amide I was shifted to lower values, suggesting thus a confinement into mesopores. Finally, the enzyme concentration effect can be demonstrated by the increment of the amide band intensity in the range of 1700-1500 cm(-1) as the amount of adsorbed enzyme increases. Thus, the textural properties of silica materials seem to be the key factor in the enzyme adsorption.

The probiotic bacteria L. rhamnosus GG (LGG) were encapsulated into core-shell alginate-silica microbeads of about 500 μm through a double step synthesis involving micro-ionogel formation by electrospraying and silica coating by the sol-gel process. Formulating microparticles with sucrose as a cryoprotectant allowed maintaining bacterial viability and cultivability upon freeze-drying for weeks, as determined by plate counting. As much as 3.4 × 1010 CFU g-1 and 4.1 × 108 CFU g-1 were observed to be cultivable in alginate and silica-coated beads after 3 weeks of freeze-drying, respectively. The viability of the released bacteria was evaluated in an in vitro batch SHIME model (a simulator of the human intestinal microbial ecosystem) by denaturing gradient gel electrophoresis (DGGE) and quantitative PCR (qPCR). It was revealed that microencapsulation efficiently protects LGG from the low gastric pH, especially in the case of silica-coated beads. Both encapsulation systems (alginate and alginate-silica) allowed for a better colonization of the colon compared with free LGG. Interestingly, although metabolically inactive in the upper digestive tract, LGG released from silica-coated beads boost their metabolism once they arrive in the colon, where they outcompete other members from the Lactobacillus community. In view of these results, we show that silica, usually used as an anti-caking agent in food powders, can play an active role in probiotics delivery and colon colonization.

The salting effect on the hydrothermal carbonisation (HTC) of two natural carbon precursors, sucrose and fish eggs, was investigated. Self-condensation of sucrose produced hydrochar microbeads whose size decreased with the salting-out effect according to Hofmeister's series. More interestingly, the condensation of sucrose on fish eggs allowed obtaining hollow hydrochar spheres whose thickness followed the same trend whereas their diameter only slightly decreased in the presence of a chaotropic salt. This finding was explained by the influence of the anions on the solubility of the hydrophobic polymers formed during HTC of sucrose combined with the denaturation of proteins from fish eggs. We thus showed for the first time that salting-in and salting-out effects may significantly influence the hydrothermal processes, which in turn is an easy and straightforward approach for tuning the structure of hydrothermal carbon materials.

International audience; A novel system of paramagnetic vesicles was designed using ion pairs of iron-containing surfactants. Unilamellar vesicles (diameter approximate to 200 nm) formed spontaneously and were characterized by cryogenic transmission electron microscopy, nanoparticle tracking, analysis, and light and small-angle neutron scattering. Moreover, for the first time, it is shown that magnetization measurements can be used to investigate self-assembly of such functionalized systems, giving information on the vesicle compositions and distribution Of surfactants between the bilayers and the aqueous bulk.

International audience; Due to their properties nano-emulsions are excellent candidates to be used as imprints to create a macropore network. In this study nano-emulsions have been formulated from the Remcopal 4/decane/water system and mineralized by a dual templating mechanism in the presence of Pluronic P123 micelles. After removing the organic matter, macro-mesostructured silica materials are obtained. Small angle X-ray scattering patterns of the materials and transmission electronic microscopy experiments show that the mesoporous network (mesopore size around 9 nm) adopts a hexagonal arrangement. Macropores have been characterized by transmission electron microscopy, scanning electron microscopy and mercury porosity. As determined by mercury porosimetry, the size of the macropores imprinted by the nano-emulsions is of about 240 nm. A second macroporosity is also detected in the micrometer range and could be related to the further fusion of nano-emulsions during the hydrothermal process and to interparticular porosity. To better address the formation mechanism of the hierarchical structure of the silica material, the stability of nano-emulsions in the presence of methanol, P123 and both of them has been investigated. We have also evidenced the dual role played by the Pluronic micelles. They do not only induce the mesopore network through the cooperative templating mechanism, but their presence also avoids the total destructuration of the nano-emulsion by methanol, released during the hydrolysis of the silica precursor.

The tautomerism of curcumin (CUR) in aqueous solution was investigated in the presence of silver nanoparticles (AgNPs) in the temperature range 294−314 K. The kinetic data indicate that the conversion of the keto-enol into the diketo form is associated to higher rate constants in comparison to those obtained in pure water. Moreover, nonlinear Arrhenius behavior was observed in the investigated temperature range. The effects of CUR on the AgNPs were determined by zeta potential and dynamic light scattering measurements and supported by spectroscopic analysis suggesting that interactions with metal surface occur preserving nanoparticles from self-aggregation in the investigated conditions. The results reported herein contribute to enhance the kinetics of CUR tautomerism in aqueous media.

The interfacial behavior of curcumin, a model anti-inflammatory drug was studied upon interaction with cetyl palmitate and 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine. Cetyl palmitate finds applications for topical delivery in nanostructured lipid carriers, while the phosphatidylcholine was used both as a component of the carrier and as a model membrane lipid. Here, surface pressure, thermodynamics, Brewster angle microscopy, molecular dynamics and polarization modulation infrared reflection-absorption spectroscopy were used to better our understanding of the interaction between the components of the delivery systems and, on the other hand, of their interaction with biological membranes. Moreover, thermodynamics was used to analyze the effect of curcumin on the lipid systems and, in particular, on the model membranes. The results obtained indicate that mixtures of curcumin and cetyl palmitate form Langmuir films, while none of the two pure components does. This effect was interpreted in terms of formation of a complex between curcumin and the hydrophobic, water insoluble cetyl palmitate. The hydrophilic-hydrophobic balance of the complex allows its penetration into the monolayer and mixing with the phospholipid phase. This finding may be of interest for further design of phytolipids for drug delivery applications.

Ductile functionalized polypropylene is of great interest in multi-layer composites development. A capped-end triblock polyether diamine (H2N-PO2-TMO9-PO3-NH2) was used as a linker of two different maleated isotactic polypropylenes (iPP-g-MAH, at 1 and 3 wt%) by twin-screw reactive extrusion. The molecular architecture, the semi-crystalline microstructure and the mechanical properties of the resulting polymers were analysed as a function of the molar ratio of NH2:MAH (0:1, 0.33:1, 0.5:1, 0.66:1, 1:1, 1.5:1, 2:1). At the molecular scale, the chemically modified polymers were characterized by FTIR and by the determination of gel content following the ASTM D2765-84 standard method. Differential Scanning Calorimetry, Wide Angle X-rays Scattering and Self Successive Auto-nucleation techniques showed the impact of the crosslinking: a decrease of the melting temperature as compared with the unmodified iPP-g-MAH polymer, as well as a decrease of the crystallinity ratio for the iPP-g-MAH at 3 wt% of MAH. Interestingly, Dynamic Mechanical Analysis and video-controlled uniaxial tensile tests showed that the polymers obtained in stoichiometric NH2:MAH molar ratio exhibit the best mechanical properties enlightened by a switch from brittle to ductile mechanical behaviour with few differences between the two iPP-g-MAH.

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Herein the survivability of free and encapsulated Lactobacillus. rhamnosus GG (LGG) in alginate or in alginate-silica microcarriers was investigated upon storage in apple juice and 5vt% beer at 4 °C. This study showed that the encapsulation approach utilized herein limits the release of the bacteria over time into the beverages, with core-shell alginate-silica beads being more efficient than alginate beads alone. Additionally, the statistical analyses showed a p

Hollow carbon spheres (HCSs), also sometimes called carbon capsules, refer to hollow structured carbon particles of millimetre, micron or even nanometre size and correspondingly thin shells. These materials are presently attracting great attention due to their unique properties such as encapsulation ability, controllable permeability, surface functionality, high surface-to-volume ratios, and excellent chemical and thermal stabilities. In many aspects, carbon capsules are therefore superior to their polymer- or metal-based counterparts. In the present review, two main synthetic strategies, hard-templating and soft-templating routes, but also far more uncommon preparation ways are reported and concisely described. The main features of the resultant HCSs are also briefly given. Recent progress in the main application aspects of HCSs, such as adsorption, energy storage and catalysis, among others, is next discussed. Finally, an outlook of their prospects and challenges in terms of controlled synthesis and applications is presented.

International audience; β-Galactosidase has been drawing increasing attention for the treatment of lactose intolerance, but its delivery has been impeded by degradation under gastric conditions. We have demonstrated that the coating of mesoporous silica microparticles (diameter ≈ 9 µm, pore size ≈ 25 nm) with dioleoylphosphatidylcholine membranes significantly improved the loading capability and protected the enzymes from the loss of function under simulated gastric conditions. Once the particles are transferred to simulated intestinal conditions, the digestion of phosphatidylcholine with pancreatin led to the release of functional β-galactosidase. The coating of mesoporous silica nanoparticles with a single phospholipid bilayer opens up a large potential towards the controlled release of orally administrated drugs or enzymes to the intestines.

There is a growing need in the industrial sector (health, nutrition and cosmetic) to discover new biomolecules with various physico-chemical and bioactive properties. Various beneficial effects of peptides - notably those produced from protein hydrolysis - are reported in the literature. The antioxidant activity involves various mechanisms, among them metal chelation, studied by UV-visible spectrophotometry. In this paper, we set up an original method of screening metal chelating peptides in a hydrolysate using Surface Plasmon Resonance (SPR) for their antioxidant properties. To date, the empirical approach used several cycles of hydrolysate fractionation and bioactivity evaluation until the isolation of the pure bioactive molecule and its identification. Besides, the detection of metal-chelating peptide is not sensitive enough by spectrophotometry. For the first time, metal chelating peptides were screened in hydrolysates using SPR and a correlation was established between affinity constant determined in SPR and metal chelation capacity determined from UV-visible spectrophotometry.

Hybrid alginate-silicate microbeads of about 10-20 μm were synthesized by combining alginate crosslinking, silica condensation in a one pot approach using a food grade emulsion as template. A fine tuning of the formulation composition (alginate, silica and calcium sources) is necessary in order to obtain core-shell microbeads instead of unshaped and irregular fragments or even perforated spherical beads. Importantly, in situ linear rheology provides insights into the reaction mechanism as a result of the rheological fingerprint profile obtained during beads formation.

Molybdenum disulfide nanoparticles are known by their high performance as solid lubricants and oil-additives thanks to their intrinsic structure and properties reducing wear and friction coefficient in different lubricating conditions. In this contribution, MoS 2 nanospheres were successfully synthesized via a facile solvothermal route under lower temperature (190°C). Then, these nanoparticles are used as additives in PAO base oils. The dispersibility and the stability of those nano-additives was enhanced using dispersants based on alkyl-silane moieties. The synthesized nano-aditives were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Fourier Transformation Infrared Spectroscopy (Ft-IR) and X-ray Analysis (EDX), while the dispersibility and the stability of the prepared suspension was studied using Dynamic Light Scattering technique and Turbiscan analysis.

Molybdenum disulfide nanoparticles attract considerable attention as solid lubricants and oil-additives thanks to their excellent lubricating properties. As additive, MoS 2 permits an excellent enhancement of oil wear and friction parameters. However, the major problem that limits its use as additive is its agglomeration that gives rise to the loss of the individual properties of nanoparticles. In this contribution, and with the aim to improve the dispensability of MoS 2 nanoparticles, a chemical surface modification of MoS 2 nanoparticles using alkyl-silane group based dispersants in Poly-a-olefin base oils (PAO4, PAO8) was studied. The agglomeration phenomena was investigated via DLS technique by measuring the nanoparticles size distribution in oil suspensions while the nanoparticles sedimentation vs. time was studied by a visual control.

International audience; Liquid foams were prepared by whipping aqueous solutions based on natural polyphenols, surfactant and crosslinker. The destabilisation mechanisms of such thick, opaque and viscous liquid foams were investigated for the first time with a light-scattering detection method using an optical analyser. The technique allowed separating processes such as drainage, coalescence and coarsening, and sedimentation, so that each of them could be investigated independently as a function of whipping time, surfactant amount, and temperature. The corresponding average bubble diameters could also be determined as a function of time. It was shown that this kind of optical analysis is quite relevant for optimising formulations and foaming conditions with the aim of recovering rigid foams after polymerisation, having a given homogeneous structure that might be useful for various applications such as thermal insulation or acoustic absorption.

The authors regret that the printed version of the above article contained some errors in the value of the lower bound of thermal conductivity considered and discussed in section 3.5. The correct and final version follows. The authors would like to apologise for any inconvenience caused. The penultimate paragraph of section 3.5 should read: ""This range, which is already unrealistically broad, was widened further to 0.02-10 W m−1 K−1, and those extreme values were tested. The results are shown in Fig. 14. It can be seen that the impact of the thermal conductivity is quite low since a change of less than 10% was obtained. This finding definitely suggests that the effect observed by Zhou et al. [4] was not attributable to some differences of thermal conductivity but to another physical properties of their HCSs, since the authors could only multiply the conductivity by a factor 1.23 (against 500 in the simulation) by changing the composition of their materials."" The new Fig. 14 is thus the following (only the legends written inside the plots are modified, not the plots themselves). Fig. 14. Calculated change of evaporation rate as a function of the position of the HCS, for two extreme values of its thermal conductivity, l (""lam"" on the plots). (b) is a zoom of (a) in the range of positions where the water evaporation changes the most. (A colour version of this figure can be viewed online.)

International audience; A new catanionic system associating amphiphilic carnosine (beta AlaHisC8) and lauric acid forms supramolecular hydrogel at a very low concentration. This gel was investigated and we checked the validity of the concept of hydrogel utilization to reduce boron leachability and to develop new wood protection treatments. Impregnation with 5% aqueous borax solution (w/w) and 0.3% gelator agent (w/w) fosters improvement in the resistance of Scots pine sapwood subjected to water leaching toward the brown-rot fungus Poria placenta, while samples treated with 5% aqueous borax solution were partially degraded by the fungus. These results clearly indicate the effectiveness of hydrogel to retain boron in wood.

beta-Galactosidase (beta-Gal) is one of the most important enzymes used in milk processing for improving their nutritional quality and digestibility. Herein, beta-Gal has been entrapped into a meso-macroporous material (average pore size 9 and 200 nm, respectively) prepared by a sol&-gel method from a silica precursor and a dispersion of solid lipid nanoparticles in a micelle phase. The physisorption of the enzyme depends on the concentration of the feed solution and on the pore size of the support. The enzyme is preferentially adsorbed either in mesopores or in macropores, depending on its initial concentration. Moreover, this selective adsorption, arising from the oligomeric complexation of the enzyme (monomer/dimer/tetramer), has an effect on the catalytic activity of the material. Indeed, the enzyme encapsulated in macropores is more active than the enzyme immobilized in mesopores. Designed materials containing &;946#-Gal are of particular interest for food applications and potentially extended to bioconversion, bioremediation, or biosensing when coupling the designed support with other enzymes., 7º Programa Marco de la UE FP7/2007-2013/, Programa People.

International audience; A novel low-molecular weight gelator based on a mixture of a cationic pseudopeptidic surfactant and lauric acid (1/3), at basic pH, is reported. The gelling properties of this system have been investigated by Infra-Red spectroscopy (FT-IR), Scanning and Transmission Electron Microscopies (SEM, TEM), and Small Angle X-ray Scattering (SAXS).

Hollow carbon spheres (HCSs), also sometimes called carbon capsules, refer to hollow structured carbon particles of millimetre, micron or even nanometre size and correspondingly thin shells. These materials are presently attracting great attention due to their unique properties such as encapsulation ability, controllable permeability, surface functionality, high surface-to-volume ratios, and excellent chemical and thermal stabilities. In many aspects, carbon capsules are therefore superior to their polymer- or metal-based counterparts. In the present review, two main synthetic strategies, hard-templating and soft-templating routes, but also far more uncommon preparation ways are reported and concisely described. The main features of the resultant HCSs are also briefly given. Recent progress in the main application aspects of HCSs, such as adsorption, energy storage and catalysis, among others, is next discussed. Finally, an outlook of their prospects and challenges in terms of controlled synthesis and applications is presented.

International audience; Ordered mesoporous carbons were prepared by the self-assembly of Mimosa tannin, a natural poly phenolic molecule, and a micellar solution of Pluronic (R) F127, used as soft template. The synthesis was carried out at 20 degrees C using water as the only solvent and without crosslinker agent (i.e., formaldehyde). When tannin, at any pH lower than 4.2, and Pluronic solutions were mixed, a phase separation mechanism immediately occurred due to the strong interaction between both polymers. The precipitated resin was recovered, dried and pyrolysed at 400, 700 and 900 degrees C. Ordered mesoporous carbon materials were obtained, having both high pore volume and surface areas, up to 0.64 cm(3) g(-1) or 720 m(2) g(-1), respectively.

Fluorinated compounds are not only more hydrophobic than their hydrogenated counterparts but also oleophobic. This makes them interesting for biomedical applications. They form a large variety of supramolecular architectures and, if appropriately designed, they spontaneously form vesicles. Herein we report the synthesis of novel monocatenar fluorinated surfactant, named F 9 NH(EO) 2 NH 2 , its use as ss DNA vector with potential applications in gene delivery or RNA interference. The molecular structure of the amphiphilic compound was designed in three parts: (i) a fluorinated hydrophobic tag responsible of self-assembling, (ii) a flexible and hydrophilic ethylenoxide moiety as polar head and (iii) a protonated at physiological pH primary amine responsible of binding. Surface tension, dynamic light scattering (DLS) measurements, and TEM studies showed that the monocatenar surfactant F 9 NH(EO) 2 NH 2 spontaneously self-assembles into vesicles. This represents another example in addition to the few existing in the literature and it highlights the unique properties of the fluorinated tail. Interactions between ss DNA and cationic monocharged F 9 NH(EO) 2 NH 2 were probed by static light scattering (SLS), fluorescence and circular dichroism (CD). F 9 NH(EO) 2 NH 2 was found to exclude ethidium bromide (EB) from ss DNA/EB complex, and this process was dependent on the ss DNA concentration and on the charge ratio surfactant to ss DNA. CD spectra showed that by increasing the surfactant concentration, ss DNA undergoes a continuous conformational transition from native B-form to a more ordered phase (Z + /Z − ≤ 3) and then to a less ordered phase (Z + /Z − ≥ 4), which confirmed the results obtained by fluorimetry and SLS measurements. Cell viability studies reveled that monocatenar fluorinated surfactant F 9 NH(EO) 2 NH 2 is not toxic for human cells (MRC-5) below 40 μM.

A simple route to fluoroalkylated functionalized secondary amines is proposed by the treatment of 2-perfluoroalkylprop-2-enoic acids with various primary amines. Two of these compounds were obtained from oxyethylenic diamine and present an amphiphilic structure. These compounds exhibit an excellent surface activity since they are lowering the surface tension to 18–20 mN/m and this, at very low concentrations (around 10 −5 M). DLS measurements and TEM studies show an original behavior of the monocatenar fluorinated surfactants 5n and 5o , which are able to spontaneously self-assembles into vesicles, and therefore it makes them suitable candidates as carriers in drug or gene delivery systems.