Institute of Nanomaterials and Nanotechnology

Rabat, Morocco

Institute of Nanomaterials and Nanotechnology

Rabat, Morocco
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Mignani S.,University of Paris Descartes | El Kazzouli S.,Institute of Nanomaterials and Nanotechnology | Bousmina M.,Hassan II Academy of science and Technology | Majoral J.-P.,CNRS Coordination Chemistry
Advanced Drug Delivery Reviews | Year: 2013

Drugs are introduced into the body by numerous routes such as enteral (oral, sublingual and rectum administration), parenteral (intravascular, intramuscular, subcutaneous and inhalation administration), or topical (skin and mucosal membranes). Each route has specific purposes, advantages and disadvantages. Today, the oral route remains the preferred one for different reasons such as ease and compliance by patients. Several nanoformulated drugs have been already approved by the FDA, such as Abelcet®, Doxil®, Abraxane® or Vivagel®(Starpharma) which is an anionic G4-poly(l-lysine)-type dendrimer showing potent topical vaginal microbicide activity. Numerous biochemical studies, as well as biological and pharmacological applications of both dendrimer based products (dendrimers as therapeutic compounds per se, like Vivagel®) and dendrimers as drug carriers (covalent conjugation or noncovalent encapsulation of drugs) were described. It is widely known that due to their outstanding physical and chemical properties, dendrimers afforded improvement of corresponding carried-drugs as dendrimer-drug complexes or conjugates (versus plain drug) such as biodistribution and pharmacokinetic behaviors. The purpose of this manuscript is to review the recent progresses of dendrimers as nanoscale drug delivery systems for the delivery of drugs using enteral, parenteral and topical routes. In particular, we focus our attention on the emerging and promising routes such as oral, transdermal, ocular and transmucosal routes using dendrimers as delivery systems. © 2013 Elsevier B.V.

Drissi L.B.,Institute of Nanomaterials and Nanotechnology | Saidi E.H.,Institute of Nanomaterials and Nanotechnology
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

Using the SU(5) symmetry of the 4D hyperdiamond and results on the study of 4D graphene given in Drissi et al., we engineer a class of 4D lattice QCD fermions whose Dirac operators have two zero modes. We show that generally the zero modes of the Dirac operator in hyperdiamond fermions are captured by a tensor Ωμl with 4×5 complex components linking the Euclidean SO(4) vector μ; and the 5-dimensional representation of SU(5). The Boriçi-Creutz (BC) and the Karsten-Wilzeck (KW) models as well as their Dirac zero modes are rederived as particular realizations of Ωμl. Other features are also given. © 2011 American Physical Society.

Drissi L.B.,Institute of Nanomaterials and Nanotechnology | Saidi E.H.,Institute of Nanomaterials and Nanotechnology | Bousmina M.,Institute of Nanomaterials and Nanotechnology
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

Mimicking pristine 2D graphene, we revisit the BBTW model for 4D lattice QCD given in by using the hidden SU(5) symmetry of the 4D hyperdiamond lattice H4. We first study the link between the H4 and SU(5); then we refine the BBTW 4D lattice action by using the weight vectors λ1, λ2, λ3, λ4, and λ5 of the five-dimensional representation of SU(5) satisfying ∑iλi=0. After that, we study explicitly the solutions of the zeros of the Dirac operator D in terms of the SU(5) simple roots α1, α2, α3, and α4 generating H4; and its fundamental weights ω1, ω2, ω3 ω4 which generate the reciprocal lattice H4*. It is shown, among others, that these zeros live at the sites of H4*; and the continuous limit D is given by id√52 γμk μ with d, γμ, and kμ standing, respectively, for the lattice parameter of H4, the usual 4 Dirac matrices and the 4D wave vector. Other features, such as differences with BBTW model as well as the link between the Dirac operator following from our construction and the one suggested by Creutz using quaternions, are also given. © 2011 American Physical Society.

El Kazzouli S.,Institute of Nanomaterials and Nanotechnology | El Brahmi N.,Institute of Nanomaterials and Nanotechnology | El Brahmi N.,CNRS Coordination Chemistry | Mignani S.,Institute of Nanomaterials and Nanotechnology | And 4 more authors.
Current Medicinal Chemistry | Year: 2012

Metallodrugs (organometallic complexes) bearing at least one metal-carbon bond-represent original and powerful tools for diverse therapeutic applications based on the development of "bioorganometallic chemistry". To date, various metallodrugs were described with very interesting biological activities as antimalarials, antibacterials, neuroprotectors, against arthritis, for chemotherapy etc. Anticancer Pt-based drugs are the main complexes used in the treatment of several cancers, but unfortunately these complexes show elicit and severe toxicities and resistance effects. The remarkably unique and tunable properties of dendrimers have made them promising tools for diverse biomedical applications such as diagnostics, gene therapy and drug delivery including in oncology. Recent studies have shown that well designed dendritic carriers overcome such as poor solubility, permeability, biocompatibility, bioavailability and toxicity of the native drug. This review reports on the recent advances for the use of metallodrugs and dendritic based carriers (drug-dendrimer conjugates and drug encapsulation) in oncology. Advantages, limitations and opportunities in oncology of such materials are discussed and compared. © 2012 Bentham Science Publishers.

El Rhazouani O.,Mohammed V University | Benyoussef A.,Mohammed V University | Benyoussef A.,Institute of Nanomaterials and Nanotechnology | Benyoussef A.,Hassan II Academy of Science and Technology | And 3 more authors.
Physica A: Statistical Mechanics and its Applications | Year: 2014

The double perovskite (DP) Sr2CrReO6, with its high Curie temperature, is a good candidate for magneto-electric and magneto-optic applications. Thus, a theoretical study by Monte Carlo Simulation (MCS) and Mean Field Approximation (MFA) in the context of the Ising model is important for a better understanding of the magnetic behavior of this material. The critical behavior of the magnetization and the susceptibility of this system have been determined. The phase diagrams depending on the exchange couplings and the crystal fields have been given. The values of critical exponents are also reported. © 2013 Elsevier B.V. All rights reserved.

Nekhlaoui S.,Mohammed V University | Essabir H.,Institute of Nanomaterials and Nanotechnology | Bensalah M.O.,Mohammed V University | Fassi-Fehri O.,Mohammed V University | And 3 more authors.
Materials and Design | Year: 2014

Extrusion and injection processes have been used to successfully prepare two systems of composite, polypropylene (PP)/clay (E1) and compatibilized polypropylene (PP-SEBS-g-MA)/clay (E1) at various particles content (5, 10, 15, 20, 25, 30wt.%). To enhance fillers wettability within the polymer, a coupling agent was added. The essential work of fracture (EWF) concept was successfully applied to the fracture toughness characterization of ductile composites. Moreover, tensile and dynamic mechanical analysis (DMA) tests were conducted for these composites to ascertain the influence of the material composition (E1 particles) on these mechanical parameters. The tensile properties results indicate that the Young's modulus has increased for whole systems reaching a gain of 60 % and 23% in binary and ternary composites, respectively, at 30wt.% particle. Clay (E1) addition markedly enhances the plastic work of fracture (We) and reduces the specific plastic work (Bwp). The thermal analysis shows an increase in initial thermal decomposition temperatures with addition of clay (E1), which normal with the addition of a high degradation temperature charge. © 2013 Elsevier Ltd.

Arrakhiz F.Z.,Institute of Nanomaterials and Nanotechnology | Arrakhiz F.Z.,Mohammed V University | El Achaby M.,Institute of Nanomaterials and Nanotechnology | El Achaby M.,Mohammed V University | And 6 more authors.
Materials and Design | Year: 2012

In this work, high density polyethylene (HDPE) was compounded with chemically treated coir fiber using a heated two roll mill. Three chemical treatments denoted silane, sodium hydroxide (NaOH) and dodecane bromide (C12) were selected to improve the interface adhesion between fibers and polyethylene matrix. The mechanical properties of these composites were evaluated and compared against those of neat polymer and untreated fibers composites. A fixed fiber loading of 20. wt.% was used in all composites. A chemical analysis using Fourier Transform Infrared spectroscopy (FTIR) was performed to see the extent of chemical modification of the fibers. Results have shown that tensile and torsional modulus exhibited a significant increase when compared to the neat HDPE. A notable increase in the Young's modulus was observed when C12 and silane were used, corresponding to 120% and 70%, respectively. The composites' ductility was also evaluated by the plastic stored energy and showed a noted increase when C12 and silane were used, an increase of 55% with C12 treatment and 23% when silane treatment was used. Such results promise many applications for composite materials. © 2012 Elsevier Ltd.

Bailly M.,Queen's University | Kontopoulou M.,Queen's University | El Mabrouk K.,Institute of Nanomaterials and Nanotechnology
Polymer | Year: 2010

The microstructure and rheology of melt compounded ethylene-octene copolymer (EOC) nanocomposites, containing different types of functionalized matrices and nanosilica particles, were investigated. The EOC matrix was functionalized via silane grafting, using monofunctional (vinyltriethylsilane-VTES) or bifunctional (vinyltriethoxysilane VTEOS) silane agents, to prepare EOC-g-VTES and EOC-g-VTEOS respectively. Two different types of silica were used, unmodified (SiO2), or modified with octylsilane (oct-SiO2). Depending on the matrix/filler combination, different types of polymer/filler interactions were present in these composites. The formation of covalent bonds between the VTEOS functionality and the hydroxyl groups present at the surface of the particles, generated strong polymer/filler interactions, resulting in improved filler dispersion. The presence of polymer/filler interactions was confirmed by bound polymer measurements. TEM micrographs revealed a fractal-like composite structure, which agreed with the exponents determined through small angle oscillatory shear rheometry (SAOS). Rheological properties in the melt state revealed significant differences, depending on the types of matrix and filler used. Time-sweep experiments showed pronounced time-dependence indicative of a tendency toward aggregation for the EOC-g-VTES-based composites. On the contrary, strong polymer/filler interactions between EOC-g-VTEOS and oct-SiO2 resulted in a stable response. During strain-sweep experiments the EOC-g-VTEOS-based composites exhibited a higher critical strain for the onset of non-linearity, indicative of stronger adhesion between the fillers and the matrix. DMA measurements showed that more energy is dissipated during the glass transition in the composites with enhanced polymer/filler interactions. © 2010 Elsevier Ltd.

Arrakhiz F.Z.,Institute of Nanomaterials and Nanotechnology | Arrakhiz F.Z.,Mohammed V University | Elachaby M.,Institute of Nanomaterials and Nanotechnology | Elachaby M.,Mohammed V University | And 5 more authors.
Materials and Design | Year: 2012

The interest in using natural fibers as reinforcement for thermoplastic polymers was attracted several studies covering both material science and green technology. The use of plant fiber requires the issue of compatibility between matrix and fibers. This study treat the effect of chemical modification (alkali treatment, etherification treatment and esterification treatment) on the Alfa fiber surface, and its impact on mechanical and thermal properties of composites. To this end, the percentage of fibers was fixed at (20. wt.%), and to evaluate the effect of each chemical modification in Alfa reinforced polypropylene (PP), based on the mechanical and thermal properties of composites. Composites containing chemically modified Alfa fibers were found to possess improved mechanical and thermal properties when compared to non-treated composite. The highest improvement in Young's modulus was observed with esterified fibers, with a 35% increase. Thermal stability is best increased using etherification-treated fiber, with gains in the temperature up to 80 °C. © 2011 Elsevier Ltd.

Drissi L.B.,Institute of Nanomaterials and Nanotechnology | Saidi E.H.,Institute of Nanomaterials and Nanotechnology | Saidi E.H.,Université Ibn Tofail | Bousmina M.,Institute of Nanomaterials and Nanotechnology
Nuclear Physics B | Year: 2010

Using the relation between the structural and the electronic properties of honeycomb, we study the hidden SU (3) symmetry of the graphene monolayer and exhibit the link with its electronic properties. We show that the conservation law of incoming and outgoing electronic momenta at each site of graphene is solved in terms of SU (3) representations; and the Fourier waves over(φ{symbol}, ̃) (kx, ky) of the hopping electron may be classified by SU (3) highest weight multiplets φ{symbol}p, q (ξ). It is also shown that the phases arctan frac(ky, kx) of the waves are quantized as frac((p + q), (p - q)) sqrt(3) with p, q positive integers. Other features are also discussed. © 2009 Elsevier B.V. All rights reserved.

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