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Toulouse, France

Nanoscience Group

Toulouse, France
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Kadu B.S.,Nanoscience Group
Journal of Drug Delivery Science and Technology | Year: 2017

Etoricoxib (ET) based formulations viz. physical mixture of ET with β-cyclodextrin (CD); ethosomal formulation of ET and CD complex (DCE); and ET are investigated against skin inflammation. These formulations are characterized using XRD, SEM, TEM and DSC, revealed the amorphous nature of DCE (particle size 0.3–0.4 μm). ET with ethosome (PDE) and ET, CD with ethosome (DCE) is prepared using varied concentrations of lecithin and ethanol; demonstrated entrapment efficiencies of 70.8 ± 4.4% and 77.5 ± 4.2% for PDE-8 and DCE-8 respectively. Kneaded complex (KC) exhibited 77.96% and 75.32% drug release in 30 min in PBS pH 7.4 and 5.5 respectively. In-vitro and ex-vivo drug permeation in phosphate buffer saline (PBS) revealed 63–82% ET permeation for DCE-8; while in rat serum DCE-8 produced higher plasma concentration of ET (3.26 ± 0.25 μg/ml) within 8 h that is maintained over 24 h. The percentage inhibition of carrageenan induced paw edema, 8 h after applying DCE-8 is found to be 77.74% higher than PDE-8 (54.1%) and one more formulation which is a mixture of ET and ethanol in proper proportion (CPD) (20.04%). Stability studies indicated that DCE-8 stored at 5 ± 3 °C shows <5% change in residual drug content after 90 days. Present work clearly demonstrates that the tailor-made formulation DCE-8 may exhibit potentiality towards transdermal delivery of ET in the treatment of skin inflammation. © 2017 Elsevier B.V.

Home > Press > FEI Partners with Five Pharmaceutical Companies, the Medical Research Council and the University of Cambridge to form Cryo-EM Research Consortium Abstract: Organizations involved in the Cambridge Pharmaceutical Cryo-EM Research Consortium will share access to cryo-electron microscopy equipment and methods and will collaborate on developing the technology to benefit pharmaceutical drug discovery research. Hillsboro, OR and London, UK | Posted on April 5th, 2016 FEI (NASDAQ: FEIC) has partnered with five pharmaceutical companies: Astex Pharmaceuticals, AstraZeneca, GlaxoSmithKline, Heptares Therapeutics, and UCB; the Medical Research Council Laboratory of Molecular Biology (MRC-LMB); and the University of Cambridge’s Nanoscience Centre, to form the “Cambridge Pharmaceutical Cryo-EM Consortium,” which is the first of its kind worldwide. As part of the three-year agreement, FEI will provide sample preparation and data collection services on a Titan Krios™ cryo-transmission electron microscope (cryo-EM) to the consortium companies for early-stage drug discovery research. The five companies involved in the consortium will share access to the microscope with colleagues from the MRC-LMB and the University of Cambridge in return for expert guidance on the use of cryo-EM technology. FEI’s Titan Krios will be installed at the Nanoscience Centre in May. Richard Henderson, pioneer in the field of cryo-EM at MRC-LMB, states, "It is delightful to know that the development of cryo-EM, which many people have worked on for many years, has now reached mainstream structural biology. It is particularly satisfying that pharmaceutical companies are keen to evaluate the approach for drug development." Prof. Sir Mark Welland, director of the Nanoscience Centre, said, “This is a great opportunity for researchers across the University to access a state-of-the-art microscope.” Cryo-EM has quickly become one of the most important techniques used by structural biologists today to obtain molecular-scale three-dimensional (3D) information about protein structures. When combined with traditional methods for structure determination, such as x-ray crystallography and nuclear magnetic resonance spectroscopy, the resulting models can reveal the structure of complex, dynamic molecular assemblies down to the scale of individual atoms. The consortium’s Titan Krios will use the Relion software package, developed by Sjors Scheres at MRC-LMB, to process the image data into a visual 3D model that helps researchers see and understand the structure and function of the protein. “Cryo-EM 3D models allow us to see and understand the workings of protein-based molecular machines that we could not analyze before because they were too large and complex or were resistant to the preparations required for other techniques,” states Peter Fruhstorfer, vice president and general manager of the Life Sciences business, FEI. “The technique was rapidly adopted by leading academic researchers and is now finding its way into early stage discovery and development in the pharmaceutical industry.” Fruhstorfer adds, “In addition to installing the Titan Krios cryo-EM system, our contribution to the consortium includes providing an application scientist that will work with the participating companies to ensure a smooth workflow throughout, from sample preparation to data collection and data processing, with a special focus on creating a standardized and robust single-particle analysis workflow.” For more information about cryo-EM and the Cambridge Pharmaceutical Cryo-EM Consortium, contact FEI at About FEI Company FEI Company (Nasdaq: FEIC) designs, manufactures and supports a broad range of high-performance microscopy workflow solutions that provide images and answers at the micro-, nano- and picometer scales. Its innovation and leadership enable customers in industry and science to increase productivity and make breakthrough discoveries. Headquartered in Hillsboro, Ore., USA, FEI has over 2,800 employees and sales and service operations in more than 50 countries around the world. More information can be found at: About the Cambridge University Nanoscience Centre The Nanoscience Centre provides open access to over 300 researchers from a variety of University Departments to the nanofabrication and characterisation facilities housed in a combination of Clean Rooms and low noise laboratories. The main activity in the building is making individual devices or structures which are only a few nanometres in size and then measuring how they work. Office space is primarily home to the Department of Engineering's Nanoscience Group, technical and administrative staff and members of other research groups who require long term access to facilities. FEI Safe Harbor Statement This news release contains forward-looking statements that include statements regarding the performance capabilities and benefits of the Titan Krios TEM and cryo-EM solution. Factors that could affect these forward-looking statements include but are not limited to our ability to manufacture, ship, deliver and install the tools, solutions or software as expected; failure of the product or technology to perform as expected; unexpected technology problems and challenges; changes to the technology; the inability of FEI, its suppliers or project partners to make the technological advances required for the technology to achieve anticipated results; and the inability of the customer to deploy the tools or develop and deploy the expected new applications. Please also refer to our Form 10-K, Forms 10-Q, Forms 8-K and other filings with the U.S. Securities and Exchange Commission for additional information on these factors and other factors that could cause actual results to differ materially from the forward-looking statements. FEI assumes no duty to update forward-looking statements. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Kittelmann M.,Johannes Gutenberg University Mainz | Rahe P.,Johannes Gutenberg University Mainz | Rahe P.,University of Utah | Gourdon A.,Nanoscience Group | Kuhnle A.,Johannes Gutenberg University Mainz
ACS Nano | Year: 2012

Elucidating molecular-scale details of basic reaction steps on surfaces is decisive for a fundamental understanding of molecular reactivity within many fields, including catalysis and on-surface synthesis. Here, the deprotonation of 2,5-dihydroxybenzoic acid (DHBA) deposited onto calcite (101;4) held at room temperature is followed in situ by noncontact atomic force microscopy. After deposition, the molecules form two coexisting phases, a transient striped phase and a stable dense phase. A detailed analysis of high-resolution noncontact atomic force microscopy images indicates the transient striped phase being a bulk-like phase, which requires hydrogen bonds between the carboxylic acid moieties to be formed. With time, the striped phase transforms into the dense phase, which is explained by the deprotonation of the molecules. In the deprotonated state, the molecules can no longer form hydrogen bonds, but anchor to the surface calcium cations with their negatively charged carboxylate group. The deprotonation step is directly confirmed by Kelvin probe force microscopy images that unravel the change in the molecular charge. © 2012 American Chemical Society.

Kittelmann M.,Johannes Gutenberg University Mainz | Nimmrich M.,Johannes Gutenberg University Mainz | Lindner R.,Johannes Gutenberg University Mainz | Gourdon A.,Nanoscience Group | Kuhnle A.,Johannes Gutenberg University Mainz
ACS Nano | Year: 2013

The bottom-up construction of functional devices from molecular building blocks offers great potential in tailoring materials properties and functionality with utmost control. An important step toward exploiting bottom-up construction for real-life applications is the creation of covalently bonded structures that provide sufficient stability as well as superior charge transport properties over reversibly linked self-assembled structures. On-surface synthesis has emerged as a promising strategy for fabricating stable, covalently bound molecular structure on surfaces. So far, a majority of the structures created by this method have been obtained from a rather simple one-step processing approach. But the on-surface preparation of complex structures will require the possibility to carry out various reaction steps in a sequential manner as done in solution chemistry. Only one example exists in literature in which a hierarchical strategy is followed to enhance structural complexity and reliability on a metallic surface. Future molecular electronic application will, however, require transferring these strategies to nonconducting surfaces. Bulk insulating substrates are known to pose significant challenges to on-surface synthesis due to the absence of a metal catalyst and their low surface energy, frequently resulting in molecule desorption rather than reaction activation. By carefully selecting a suitable precursor molecule, we succeeded in performing a two-step linking reaction on a bulk insulating surface. Besides a firm anchoring toward the substrate surface, the reaction sites and sequential order are encoded in the molecular structure, providing so far unmatched reaction control in on-surface synthesis on a bulk insulating substrate. © 2013 American Chemical Society.

Kittelmann M.,Johannes Gutenberg University Mainz | Rahe P.,Johannes Gutenberg University Mainz | Nimmrich M.,Johannes Gutenberg University Mainz | Hauke C.M.,Johannes Gutenberg University Mainz | And 2 more authors.
ACS Nano | Year: 2011

On-surface synthesis in ultrahigh vacuum provides a promising strategy for creating thermally and chemically stable molecular structures at surfaces. The two-dimensional confinement of the educts, the possibility of working at higher (or lower) temperatures in the absence of solvent, and the templating effect of the surface bear the potential of preparing compounds that cannot be obtained in solution. Moreover, covalently linked conjugated molecules allow for efficient electron transport and are, thus, particularly interesting for future molecular electronics applications. When having these applications in mind, electrically insulating substrates are mandatory to provide sufficient decoupling of the molecular structure from the substrate surface. So far, however, on-surface synthesis has been achieved only on metallic substrates. Here we demonstrate the covalent linking of organic molecules on a bulk insulator, namely, calcite. We deliberately employ the strong electrostatic interaction between the carboxylate groups of halide-substituted benzoic acids and the surface calcium cations to prevent molecular desorption and to reach homolytic cleavage temperatures. This allows for the formation of aryl radicals and intermolecular coupling. By varying the number and position of the halide substitution, we rationally design the resulting structures, revealing straight lines, zigzag structures, and dimers, thus providing clear evidence for the covalent linking. Our results constitute an important step toward exploiting on-surface synthesis for molecular electronics and optics applications, which require electrically insulating rather than metallic supporting substrates. © 2011 American Chemical Society.

Renaud N.,Northwestern University | Ratner M.A.,Northwestern University | Joachim C.,Nanoscience Group
Journal of Physical Chemistry B | Year: 2011

We present a simple method to compute the transmission coefficient of a quantum system embedded between two conducting electrodes. Starting from the solution of the time-dependent Schrodinger equation, we demonstrate the relationship between the temporal evolution of the state vector,ψ(t), initially localized on oneelectrode and the electronic transmission coefficient, T(E). We particularly emphasize the role of the oscillation frequency and the decay rate of ψ(t)in the line shape of T(E). This method is applied to the well-known problems ofthe single impurity, two-site systems and the benzene ring, where it agrees with well-accepted time-independent methods and gives new physical insight to the resonance and interference patterns widely observed in molecular junctions. © 2011 American Chemical Society.

Kadu B.S.,Nanoscience Group | Sathe Y.D.,Nanoscience Group | Ingle A.B.,Nanoscience Group | Chikate R.C.,Nanoscience Group | And 2 more authors.
Applied Catalysis B: Environmental | Year: 2011

The remediation of Cr(VI) from simulated water streams is investigated using Fe-Ni bimetallic nanoparticles (Fe-Ni NPs) and their nanocomposites prepared with montmorillonite (MMT) clay. These nanocomposites are characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area analyses. XRD analysis revealed proper dispersion as well as intercalation of Fe-Ni NPs in the clay matrix. TEM of nanocomposites showed the presence of spherical particles having a size of 20-40nm. Batch experiments with a 25mgL-1 Cr(VI) solution and 2gL-1 Fe-Ni NPs exhibited complete reduction of Cr(VI) within 10min that follows first order reaction kinetics. Amongst 25%, 50%, 75% in situ and loaded nanocomposites, 75% compositions possess better activity with enhanced reduction capacity below pH 4 due to generation of reactive H species. XPS analysis of nanocomposites after Cr(VI) treatment suggested that reduction process occurs through Cr(III) formation followed by its subsequent reduction to Cr(0). Their potentiality towards reusage is established from the recycling experiments that revealed the order of efficiency as 75% in situ>Fe-Ni NPs>75% loaded nanocomposites. © 2011 Elsevier B.V.

Kadu B.S.,Nanoscience Group | Chikate R.C.,Nanoscience Group
Chemical Engineering Journal | Year: 2013

To improve the adsorptive mineralization efficiency of Fe-Ni nanoparticles (Fe-Ni NP's), we demonstrate a facile, rational and highly efficient approach by intercalating Fe-Ni NP's onto montmorilonite (MMT). XRD analysis suggested formation of MMT-composites with Fe-Ni NP's having spherical shape of 30-40. nm size. Kinetics of basic magenta (BM) demonstrated it to be of pseudo-second order with 25% in-situ and 10% loaded nanocomposites exhibiting better adsorption tendency. The adsorption properties of BM are analyzed with isotherms like Redlich-Peterson, Dubinin-Radushkevich, Temkin and Flory-Huggins besides Langmuir and Freundlich for understanding the adsorption dynamics. Pseudo-multilayer exothermic chemisorption is predominant with significant amount of free energy change (δ. G°) involved in adsorption on the nanocomposite surface. Employing Webber-Morris and Boyd intra-particle diffusion models, it is observed that diffusion is within micro- and meso-pores that subsequently favors pore-diffusion controlled process. These features have significantly contributed towards successful utilization of these composites for continuous removal capabilities. From the adsorption capacity, kinetics and diffusion controlled characteristics; it is observed that in-situ formed Fe-Ni nanocomposites possess enhanced adsorption capacity towards BM remediation. Present work clearly demonstrates that tailor-made nanocomposites may exhibit potential applications towards continuous removal of organic pollutants from aqueous streams with high efficiency. © 2013 Elsevier B.V.

Petkar D.R.,Nanoscience Group | Kadu B.S.,Nanoscience Group | Chikate R.C.,Nanoscience Group
RSC Advances | Year: 2014

A highly chemoselective catalytic transfer hydrogenation (CTH) of nitroarenes to corresponding amino derivatives is achieved with Fe-Ni bimetallic nanoparticles (Fe-Ni NP's) as the catalyst and NaBH4 at room temperature. Their catalytic efficiency is ascribed to the presence of Ni sites on the bimetallic surface that not only hinder the surface corrosion of the iron sites but also facilitate efficient electron flow from the catalyst surface to the adsorbed nitro compounds. This facet is corroborated with reusability studies as well as surface characterization of the catalyst before and after its repetitive usage. Thus, these nanoparticles efficiently catalyze the reduction of functionalized nitroarenes to corresponding amines without use of corrosive agents like base or other additives under ambient conditions and are easily separated by a laboratory magnet in an eco-friendly manner. © 2014 The Royal Society of Chemistry.

Kadu B.S.,Nanoscience Group | Chikate R.C.,Nanoscience Group
Journal of Environmental Chemical Engineering | Year: 2013

The reductive removal of Cr(VI) is investigated with zero-valent iron, Fe-Ni bimetallic nanoparticles and Fe-Ni bimetallic-montmorillonite nanocomposites. XRD and TEM studies reveal generation of active sites on nanocomposites possessing increased surface area.The removal of Cr(VI) follows pseudo-second order rate model with 2 g L-1 composite loading with sorption capacity (qe) in the range of 30-50 mg g-1 for the composites. Employing adsorption isotherms like Langmuir, Freundlich, Redlich-Peterson, Dubinin-Radushkevich (D-R), Temkin and Flory-Huggins (F-H), it is observed that adsorption process essentially follows pseudo-multilayer exothermic chemisorption process with free energy of adsorption (DG) in the range of -10 to -15 KJ mol-1. Pore diffusion is predominant as compared to film diffusion process; evaluated from intra-particle diffusion models, augurs well for stronger ionic interactions between Cr(VI) ions and adsorbents. The improved efficiency of composites may be attributed to the large number of available surface Fe0 atoms that significantly contributes towards reduction of adsorbed Cr(VI) on the surface. XPS measurements of composites after last cycle clearly establish the fact that formation of surface hydroxides mediates efficient flow of electron from bulk to Cr(VI) suggesting their potential usage for continuous removal capabilities. © 2013 Elsevier Ltd. All rights reserved.

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