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Dendritic mesoporous organosilica nanoparticles (DMON) are a new class of biodegradable nanoparticles suitable for biomolecule delivery. We studied the photochemical internalization (PCI) and photodynamic therapy (PDT) of DMON to investigate new ways for DMON to escape from the endosomes-lysosomes and deliver biomolecules into the cytoplasm of cells. We added photosensitizers in the framework of DMON and found that DMON were loaded with siRNA or FVIII factor protein. We made four formulations with four different photosensitizers. The photosensitizers allowed us to perform imaging of DMON in cancer cells, but the presence of the tetrasulfide bond in the framework of DMON quenched the formation of singlet oxygen. Fortunately, one formulation allowed us to efficiently deliver proapoptotic siRNA in MCF-7 cancer cells leading to 31% of cancer cell death, without irradiation. As for FVIII protein, it was loaded in two formulations with drug-loading capacities (DLC) up to 25%. In conclusion, DMON are versatile nanoparticles capable of loading siRNA and delivering it into cancer cells, and also loading FVIII protein with good DLC. Due to the presence of tetrasulfide, it was not possible to perform PDT or PCI.

L-ascorbic acid (LAA), commonly known as vitamin C, is an excellent and recognized antioxidant molecule used in pharmaceutical and cosmetic formulations. Several strategies have been developed in order to preserve its chemical stability, connected with its antioxidant power, but there is little research regarding the employment of natural clays as LAA host. A safe bentonite (Bent)—which was verified by in vivo ophthalmic irritability and acute dermal toxicity assays—was used as carrier of LAA. The supramolecular complex between LAA and clay may constitute an excellent alternative, since the molecule integrity does not seem to be affected, at least from the point of view of its antioxidant capacity. The Bent/LAA hybrid was prepared and characterized through ultraviolet (UV) spectroscopy, X-ray diffraction (XRD), infrared (IR) spectroscopy, thermogravimetric analysis (TG/DTG) and zeta potential measurements. Photostability and antioxidant capacity tests were also performed. The LAA incorporation into Bent clay was demonstrated, as well as the drug stability due to the Bent photoprotective effect onto the LAA molecule. Moreover, the antioxidant capacity of the drug in the Bent/LAA composite was confirmed.

In our study, we focused on the optimization of synthesis ZnO nanoparticles by modified sol–gel method using ZnCl2 as precursor and two different surfactants cetyltrimethylammonium bromide (CTAB) as cationic and triblock copolymer pluronic (EO106 PO70 EO106, F127) as the nonionic one. Therefore, the addition of two organic surfactants is important due to their influence on physicochemical properties. From analysis, the ZnO synthesis parameters were optimized using the response surface methodology (RSM) for optimal recoveries of synthesis. In fact, the structural, crystallite size, morphological, thermal stability, surface area, and optical properties of the ZnO nanoparticles are well characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Nitrogen adsorption-desorption N2, UV–visible and photoluminescence PL. The XRD confirms the formation of pure wurtzite ZnO phase with crystallite size in the range of 27.6–36.6 nm, SEM and TEM shows spherical and nanobattonet ZnO particles depending of surfactant used. From the optical studies, it is found that the band gap energy increase from 3.10 to 3.18 eV with the increase in the surfactant concentrations of CTAB and pluronic F127. The effects of type surfactant on the photocatalytic activity of ZnO nanoparticles were examined by the degradation of Rhodamine B in water under UV irradiation and sunlight. As a result, ZnO has higher photocatalytic activity for the degradation of Rhodamine B under UV irradiation and sunlight. This process was described by the pseudo-first-order kinetic model and Z2F which prepared with pluronic F127 has an excellent response after degradation.

International audience; The preparation of two cyclens both possessing two triethoxysilyl groups through click chemistry is described. These two cyclens were incorporated into bis(triethoxysilyl)ethenylene‐based periodic mesoporous organosilica nanoparticles (PMO NPs) at different proportions of bis(triethoxysilyl)ethenylene/cyclens (90/10, 75/25). The obtained nanorods were analyzed with different techniques and showed high specific surface areas at low proportion of cyclens. The nanorods containing free amino groups of cyclen were then used for Ni(II) and Co(II) removal from model solutions. The kinetics and isotherms of adsorption of Ni(II) and Co(II) were determined, and the materials showed high uptake of metals (up to 3.9 mmol ⋅ g−1). They demonstrated pronounced selectivity in separation of rare earth elements from late transition metals, e. g. Ni(II) and Co(II) by adsorption and even more so by controlled desorption..

In the framework of a protein–ligand-fishing strategy to identify proteins that bind to trans-resveratrol, a natural phenolic compound with pharmacological benefits, we have developed magnetic nanoparticles covalently linked to trans-resveratrol through three different derivatives and examined their aggregation behavior in aqueous solution. The monodispersed magnetic core (18 nm diameter) with its mesoporous silica shell (93 nm diameter) exhibited a notable superparamagnetic behavior useful for magnetic bioseparation. The hydrodynamic diameter, deduced from dynamic light scattering analysis, of the nanoparticle increased from 100 to 800 nm when the aqueous buffer changed from pH 10.0–3.0. A size polydispersion occurred from pH 7.0–3.0. In parallel, the value of the extinction cross section increased according to a negative power law of the UV wavelength. This was mainly due to light scattering by mesoporous silica, whereas the absorbance cross section remained very low in the 230–400 nm domain. The three types of resveratrol-grafted magnetic nanoparticles exhibited similar scattering properties, but their absorbance spectrum was consistent with the presence of trans-resveratrol. Their functionalization increased their negative zeta potential when pH increased from 3.0 to 10.0. The mesoporous nanoparticles were monodispersed in alkaline conditions, where their anionic surface strongly repulsed each other but aggregated progressively under van der Waals forces and hydrogen bonding when negative zeta potential decreased. The characterized results of nanoparticle behavior in aqueous solution provide critical insight for further study of nanoparticles with proteins in biological environment.

Organosilica nanoparticles hold great promise for nanomedicine applications. These nanoparticles are synthesized from polytrialkoxysilylated precursors without any silica source. In this work we present two kinds of organosilica nanoparticles with either amine or ammonium walls constituting their structure. Both types of nanoparticles are very efficient for gemcitabine monophosphate delivery, a small hydrophilic anticancer drug whose encapsulation is still a challenge. The nanoparticles are endocytosed by MCF-7 breast cancer cells as monitored by confocal microscopy. They are efficient and lead to 60% cancer cell death.

Theoretical and experimental characterization methods have been combined to shed more light on the potential impact of the various templating amines that they may have on the formation of layered v...

International audience; The synthesis through click chemistry of triethoxysilylated cyclen derivative-based ligands is described. Different methods were used such as the copper catalyzed Huisgen's reaction, or thiol-ene reaction for the functionalization of the cyclen scaffold with azidopropyltriethoxysilane or mercaptopropyltriethoxysilane, respectively. These ligands were then grafted on magnetic mesoporous silica nanoparticles (MMSN) for extraction and separation of Ni(II) and Co(II) metal ions from model solutions. The bare and ligand-modified MMSN materials revealed high adsorption capacity (1.0-2.13 mmol g À1) and quick adsorption kinetics, achieving over 80% of the total capacity in 1-2 hours.

The advantages of alternative energy inputs in the preparation of several hydantoins are herein illustrated through examples encompassing traditional methods and new synthetic strategies. When possible, for the same transformation, the advantages and disadvantages of each enabling technology are critically discussed and compared. Special emphasis is given to mechanochemical procedures involving the preparation of hydantoin-based active pharmaceutical ingredients (APIs), commodity chemicals for the industry, and nanohybrid materials for potentially new biomedical applications.

International audience; The world of biomedical research is in constant evolution, requiring more and more conditions and norms through pre-clinic and clinic studies. Nanodiamonds (NDs) with exceptional optical, thermal and mechanical properties emerged on the global scientific scene and recently gained more attention in biomedicine and bioanalysis fields. Many problematics have been deliberated to better understand their in vitro and in vivo efficiency and compatibility. Light was shed on their synthesis, modification and purification steps, as well as particle size and surface properties in order to find the most suitable operating conditions. In this review, we present the latest advances of NDs use in bioapplications. A large variety of subjects including anticancer and antimicrobial systems, wound healing and tissue engineering management tools, but also bioimaging and labeling probes are tackled. The key information resulting from these recent works were evidenced to make an overview of the potential features of NDs, with a special look on emerging therapeutic and diagnosis combinations.

We have examined the trans-resveratrol/lipase interaction by quantitative and qualitative analyses of fluorescence spectra, molecular docking and quantum-chemical calculations at DFT level. Interactions of CpLIP2 from C. parapsilosis CBS 604 and trans-resveratrol were confirmed with a major contribution of tryptophan residues to fluorescence quenching. A thermodynamic study across a wide temperature range was consistent with the presence of a single binding site with a binding free energy of −24 kJ/mol. Nevertheless, trans-resveratrol competitively inhibited CpLIP2 activity. Molecular docking and quantum-chemical calculations were consistent with a strong binding of trans-resveratrol to the CpLIP2 catalytic site via electrostatic and hydrophobic forces. The structural analysis quantitatively revealed an energy transfer from W51 and W350 to trans-resveratrol with a distance of 32 A. Precise understanding of trans-resveratrol/CpLIP2 interactions has important implications on lipases for screening of stilbenoid.

International audience; Herein we report the modulation of the properties of mesoporous silica nanoparticles (NPs) via various synthetic approaches. Three types of elaborations were compared, one in aqueous media at 25 °C, and the other two at 80 °C in water or in a water–ethanol mixture. For all these methods, an alkoxysilylated two-photon photosensitizer (2PS) was co-condensed with tetraethylorthosilicate (TEOS) in the presence of cetyltrimethylammonium bromide (CTAB), leading to five two-photon-sensitive mesoporous silica (M2PS) NPs. The M2PS NP porous structure could be tuned from radial to worm-like and MCM-41 types of organization. Besides, the 2PS precursor spatial dispersion was found to be highly dependent on both the 2PS initial concentration and the elaboration process. As a result, two-photon properties were modulated by the choice of the synthesis, the best results being found in aqueous media at 25 or 80 °C. Finally, the M2PS NPs were used for in vitro two-photon imaging of cancer cells.

Periodic Mesoporous Organosilica Nanoparticles (PMONPs) are nanoparticles of high interest for nanomedicine applications. These nanoparticles are not composed of silica (SiO2). They belong to hybrid organic&ndash, inorganic systems. We considered using these nanoparticles for CO2 release as a contrast agent for High Intensity Focused Ultrasounds (HIFU). Three molecules (P1&ndash, P3) possessing two to four triethoxysilyl groups were synthesized through click chemistry. These molecules possess a tert-butoxycarbonyl (BOC) group whose cleavage in water at 90&ndash, 100 &deg, C releases CO2. Bis(triethoxysilyl)ethylene E was mixed with the molecules Pn (or not for P3) at a proportion of 90/10 to 75/25, and the polymerization triggered by the sol-gel procedure led to PMONPs. PMONPs were characterized by different techniques, and nanorods of 200&ndash, 300 nm were obtained. These nanorods were porous at a proportion of 90/10, but non-porous at 75/25. Alternatively, molecules P3 alone led to mesoporous nanoparticles of 100 nm diameter. The BOC group was stable, but it was cleaved at pH 1 in boiling water. Molecules possessing a BOC group were successfully used for the preparation of nanoparticles for CO2 release. The BOC group was stable and we did not observe release of CO2 under HIFU at lysosomal pH of 5.5. The pH needed to be adjusted to 1 in boiling water to cleave the BOC group. Nevertheless, the concept is interesting for HIFU theranostic agents.

1) Background: Nanomedicine has recently emerged as a promising field, particularly for cancer theranostics. In this context, nanoparticles designed for imaging and therapeutic applications are of interest. We, therefore, studied the encapsulation of upconverting nanoparticles in mesoporous organosilica nanoparticles. Indeed, mesoporous organosilica nanoparticles have been shown to be very efficient for drug delivery, and upconverting nanoparticles are interesting for near-infrared and X-ray computed tomography imaging, depending on the matrix used. (2) Methods: Two different upconverting-based nanoparticles were synthesized with Yb3+-Er3+ as the upconverting system and NaYF4 or BaLuF5 as the matrix. The encapsulation of these nanoparticles was studied through the sol-gel procedure with bis(triethoxysilyl)ethylene and bis(triethoxysilyl)ethane in the presence of CTAB. (3) Results: with bis(triethoxysilyl)ethylene, BaLuF5: Yb3+-Er3+, nanoparticles were not encapsulated, but anchored on the surface of the obtained mesoporous nanorods BaLuF5: Yb3+-Er3+@Ethylene. With bis(triethoxysilyl)ethane, BaLuF5: Yb3+-Er3+ and NaYF4: Yb3+-Er3+nanoparticles were encapsulated in the mesoporous cubic structure leading to BaLuF5: Yb3+-Er3+@Ethane and NaYF4: Yb3+-Er3+@Ethane, respectively. (4) Conclusions: upconversion nanoparticles were located on the surface of mesoporous nanorods obtained by hydrolysis polycondensation of bis(triethoxysilyl)ethylene, whereas encapsulation occurred with bis(triethoxysilyl)ethane. The later nanoparticles NaYF4: Yb3+-Er3+@Ethane or BaLuF5: Yb3+-Er3+@Ethane were promising for applications with cancer cell imaging or X-ray-computed tomography respectively., This research was funded by ANR NanoptPDT. SR thanks the Erasmus Mundus program for a grant. This work has been supported by the Spanish Ministry of Science, Innovation and Universities (RTI2018-094426-B-I00).

Liquid wastes containing non-ferrous heavy metal ions and some radionuclides, 137Cs and 90Sr in particular, represent one of the most dangerous sources of environmental contamination. The remediation of wastewater containing such pollutants continue to be among the biggest challenges of Sustainable Development and Environmental Safety. Sorption-based technologies have proven their efficiency also in reducing the radionuclide content in aqueous streams to low-level residual activity, with the concomitant decrease in the amount of ultimate solid waste generated. Although sorption of cesium and strontium by resins, clays, and zeolites has been investigated intensively and even used in real applications, there is still considerable scope for improvement in terms of retention capacity and selectivity. Recent progress in design and preparation of nanostructured inorganic materials has attracted growing interest based on the potential for improving the retention performance when coupling such functionalities as ion exchange capacity, structural flexibility that may result in steric retention effects, as well as the propensity to interact specifically with the target metal cations. Titanate, vanadate, and tungsten based materials, manganese oxides, hexacyanoferrates, metal sulfides, ammonium molybdophosphates, or hydroxyapatite, characterized by various structures and morphologies, are reviewed with the emphasis being put on synthesis and shaping of such materials, their structure in relationship with the capacity and selectivity of trapping cesium and strontium from either single or multi-component aqueous solutions, as well as the possible retention mechanism. The potential candidates for remediation uses are selected with regard to their sorption capacity and distribution coefficient towards target cations, and also the pH window for an optimum cation capture.

Hybrid nanoparticles with a large bridging organic group were prepared by mechanochemical-assisted sol–gel reaction. Planetary ball mill (PBM) was used for the first time to access the bis-silylated precursors, containing complex functionalities (such as hydantoins or a symmetrical urea obtained from α-amino esters). The process is based on a sequential reaction pathway involving liquid-assisted grinding (LAG) and 1,1′-carbonyldimidazole (CDI)-mediated one-pot/two-step reactions. Then hydantoins and the symmetric urea were used for the one-pot preparation of the corresponding bis-silylated compounds in a vibrational ball mill (VBM), followed by the mechanochemical sol–gel preparation of biohybrid bridged silsesquioxane nanospheres of uniform size.

The present paper examines the impact that the nanotube morphology and organic or inorganic intercalated species may have on the cesium sorption by layered vanadium oxides prepared with the use of hexadecylamine as a structure-directing agent. The hybrid material represented by a chemical formula of (V2O5)(VO2)1.03(C16H36N)1.46(H2O)x was achieved through accelerated microwave-assisted synthesis carefully optimized to ensure the best compromise between the scroll-like morphology and the hydrophobic character. To enhance its dispersibility in water, this sample was subsequently modified by progressive replacement of the C16H36N+ units by NH4+ cations. The final materials represented a stacking of lamellar sheets with a worse scroll-like morphology. Both the optimization procedure and the template removal were monitored on the basis of scanning and transmission electronic microscopy, X-ray diffraction, infra-red spectroscopy, inductively coupled plasma-optical emission spectrometry, X-ray photoelectron spectroscopy, and elemental analysis, supplemented by adequate simulations methods providing the reference IR spectra and XRD patterns for comparison or the textural parameters of the samples. The comparison of the cesium sorption from either a 4:1 ethanol–water mixture or aqueous solutions pointed toward the solubility of intercalated cations in the bulk solution as the main factor limiting their displacement from the interlayer space by the oncoming cesium ones. The sample obtained after 70% exchange with NH4+ exhibited a maximum sorption capacity of 1.4 mmol g−1 from CsNO3 aqueous solutions and its retention efficiency remained significant from low-concentration Cs solutions in river or sea water.

The synthesis and application of mesoporous silica nanoparticles (MSN) and mesoporous silica nanorods (MSNR) for drug delivery were described. MSN or MSNR were obtained by adjusting the amount of added cosolvent to the sol-gel solution. Therefore, the addition of ethanol (EtOH) has contributed to the control of the particle shape and to the structure of the mesoporosity. MSN and MSNR particles were then loaded with doxorubicin and incubated with MCF-7 breast cancer cells. MSN and MSNR particles were efficient in killing cancer cells but their behavior in drug delivery was altered on account of the difference in their morphology. MSN showed a burst release of doxorubicin in cells whereas MSNR showed a sustained delivery of the anti-cancer drug.

We report a new approach for the synthesis of multifunctional Au core@Prussian Blue analogous (PBA) shell nanoheterostructures that involves PBA shell growth on the surface of cyanide-stabilized gold nanoparticles. It permits the assembly of Au@KNiII[FeII(CN)6] core@shell and Au@KNiII[FeII(CN)6]@KNiII[CrIII(CN)6] core@shell@shell heterostructures with well-defined and size-controlled gold cores and PBA shells. These heterostructures exhibit tunable size- and shape-dependent magnetic and optical properties: (i) the surface plasmon resonance band position and intensity mainly depend on the PBA shell thickness, and (ii) the magnetic properties (the transition temperature, the coercivity, and magnetic regime) depend in a complex manner on the thickness as well as the particular morphology of the magnetic shell.

The synthesis of degradable gold core–mesoporous organosilica shell nanoparticles is described. The nanoparticles were very efficient for two-photon luminescence imaging of cancer cells and for in vitro gemcitabine monophosphate delivery, allowing promising theranostic applications in the nanomedicine field.

Porphyrin- or phthalocyanine-bridged silsesquioxane nanoparticles (BSPOR and BSPHT) were prepared. Their endocytosis in MCF-7 cancer cells was shown with two-photon excited fluorescence (TPEF) imaging. With two-photon excited photodynamic therapy (TPE-PDT), BSPOR was more phototoxic than BSPHT, which in contrast displayed a very high signal for photoacoustic imaging in mice.

A simple original route is used to produce boron nanomaterials at room temperature, which is attractive compared to already known methods. Accordion shaped amorphous boron nanomaterials are elaborated. Very unusual morphologies are obtained from an original approach based on the direct oxidation of a solid state LixB alloy used as a boron precursor. The amorphous and nanosized materials produced in this controlled reaction of hydrolysis are characterized using electron microscopy, gas sorption methods, light scattering diffusion, X-ray diffraction, IR and Raman spectroscopies. Regular and residue free thin deposits on metal plates, tested as neutron detectors, display good efficiency in neutron detection.

Silver-derivatized silica particles possessing a non-spherical morphology and surface plasmon resonance properties have been achieved. Nanometer-sized silica rods with uniformly sized mesopore channels were prepared first making use of alkyltrimethyl ammonium surfactants as porogens and the 1:0.10 tetraethyl orthosilicate (TEOS) : 3-aminopropyltriethoxysilane (APTES) mixture as a silicon source. Silica rods were subsequently functionalized by introducing elongated silver nanoparticles within the intra-particle mesopores thanks to the AgNO3 reduction procedure based on the action of hemiaminal groups previously located on the mesopore walls. The textural and structural features of the samples were inferred from the combined characterization studies including SEM and TEM microscopy, nitrogen adsorption-desorption at 77 K, powder XRD in the small- and wide-angle region, as well as UV–visible spectroscopy. 129Xe NMR spectroscopy appeared particularly useful to obtain a correct information about the porous structure of rod-shaped silica particles and the silver incorporation within their intra-particle mesopores.

International audience; Mesoporous organosilica nanoparticles (PHT-PMO) have been prepared from an octa-triethoxysilylated Zn phthalocyanine precursor. These PHT-PMO nanoparticles had no dark toxicity but high phototoxicity when irradiated at 650 nm, and remarkable near-infrared phototoxicity when excited at 760 and 810 nm. The PHT-PMO were then aminated to promote electrostatic complexation with siRNA. Transfection experiments were performed upon NIR irradiation and photochemical internalization was very efficient, leading to 65% luciferase extinction in MCF-7 cancer cells expressing stable luciferase.

In recent years, research on enabling energy sources capable of promoting chemical reactions with low environmental impact and useful to drive the development of innovative, green, and sustainable processes has been continuously growing. We report herein selected examples based on the use of mechanochemistry as a valid and reliable alternative to chemistry in solution for the preparation of pharmaceutical materials, active co-crystals, or hybrid nanoparticles.

International audience; The preparation of hydantoin scaffolds using modern non-conventional activation methods is herein described. Special attention is devoted to the preparation of hydantoin-based Active Pharmaceutical Ingredients (APIs) by mechanochemistry, highlighting its advantages compared to classical solution procedures, opening new perspectives in the sustainable preparation of useful scaffolds for the pharmaceutical industry.

An alternative microwave-assisted hydrothermal route for the preparation of manganate nanoflowers under basic conditions has been proposed in view of potential uses in selective retention of strontium from multicomponent aqueous streams. Based on the combination of such characterization techniques as Scanning and Transmission Electronic Microscopy, X-ray photoelectron spectroscopy, and X-ray Diffraction, as well as taking advantage of the computer-aided structure simulation, homogeneous nanoflower morphology possessing a layered structure and K+ compensating cations was evidenced as corresponding to the KMn4O8 chemical formula. The nanoflower sample was subsequently tested for the selective adsorption of strontium and cesium by measuring the individual adsorption isotherms from single-solute and multicomponent aqueous solutions. The material appeared selective towards strontium against cesium even in multicomponent solutions provided that the concentration of calcium remained low. This difference in the retention selectivity was rationalized based on the Density Functional Theory (DFT) calculations of the energy of adsorption and direct calorimetry measurements of the enthalpy of displacement for the individual cations.

International audience; (1) Background: Nanomedicine has recently emerged as a new area of research, particularly to fight cancer. In this field, we were interested in the vectorization of pepstatin A, a peptide which does not cross cell membranes, but which is a potent inhibitor of cathepsin D, an aspartic protease particularly overexpressed in breast cancer. (2) Methods: We studied two kinds of nanoparticles. For pepstatin A delivery, mesoporous silica nanoparticles with large pores (LPMSNs) and hollow organosilica nanoparticles (HOSNPs) obtained through the sol-gel procedure were used. The nanoparticles were loaded with pepstatin A, and then the nanoparticles were incubated with cancer cells. (3) Results: LPMSNs were monodisperse with 100 nm diameter. HOSNPs were more polydisperse with diameters below 100 nm. Good loading capacities were obtained for both types of nanoparticles. The nanoparticles were endocytosed in cancer cells, and HOSNPs led to the best results for cancer cell killing. (4) Conclusions: Mesoporous silica-based nanoparticles with large pores or cavities are promising for nanomedicine applications with peptides.

The synthesis of hollow organosilica nanoparticles is described from bis triethoxysilylpropyldisulfide and bis(trimethoxylsilylpropyl)methylamine. The nanoparticles were monodisperse with a mean diameter of 90 nm, and the adsorption−desorption properties of these nanoparticles were investigated with nitrogen at 77 K, n-hexane, and water. The nanoparticles were nonporous at 77 K as shown by N2 sorption analyses. n-Hexane interacted reversibly through physisorption with the nanoparticles, whereas water showed a strong nonreversible interaction, probably because of chemisorption with nitrogen atom sites. Amoxicillin antibiotic was loaded with these nanoparticles and the loading capacity was 30%. Ag+ ions were also adsorbed with amoxicillin, and the multifunctional nanoparticles were efficient in inhibiting bacterial growth with a synergy between the antibiotic delivery and Ag+ release.