1,721,133 research outputs found
L’unione fa la forza! Approccio combinato computazionale/sperimentale allo studio di materiali nanostrutturati
No full textNano tools for macro problems: multiscale molecular modeling for functional hybrid materials.
No full textThe long and winding road.Multiscale molecular modeling approach to the self-assembly of di/triblock copolymers for drug delivery in aqueous solution
No full textMulholland Dr. Multiscale molecular modeling of the self-assembly of di/triblock copolymers for drug delivery
No full textNano tools for macro problems: multiscale molecular modeling of nanostrucured polymer systems
No full textA current challenge of physical, chemical, and engineering sciences is to develop theoretical tools for predicting structure and properties of complex materials from the knowledge of a few input parameters. In this work, we present a general multiscale molecular simulation protocol for predicting morphologies and properties of nanostructured polymer systems and we apply it to three examples of industrial relevance. The first example is of general importance for the polymer industry and is related to the enhancement of mechanical and barrier properties, if a nanofiller is dispersed into a polymer matrix: the role of multiscale modeling for the development of the material in the stage of screening, the best design is evidenced. The second example, important for the optoelectronic industry, is related to the prediction of the dispersion of gold nanoparticles into a diblock copolymer system forming different nanostructures (lamellae, cylinders, ...). In this case, it is relevant to understand how it is possible to influence the self-assembly of the nanoparticles in different regions of the diblock copolymer structure. The third example is of interest to automotive and polymer industries and involves inorganic nanoparticles grafted with organic side chains. The assembly is dispersed in a polymeric matrix and it is interesting to predict the effect of the chain length and grafting density on the nanostructure
To the nanoscale and beyond! Multiscale molecular modelling of polymer-clay nanocomposites
No full textComplexes between poly(amido amine) dendrimers and poly(methacrlyic acid): insight from molecular dynamics simulations
No full textIn this work we present results from fully atomistic molecular dynamics simulations of aqueous solutions of poly(amido amine) dendrimers and poly(methacrylic) acid in the dilute regime and at low ionic strength and physiological pH conditions, in which the polymeric components are charged. We have studied stoichiometric (1:1) and non-stoichiometric (1:2) systems, comprised by dendrimers of two different generations and two different lengths of the linear polyelectrolyte. For all systems studied, a polymer-rich and a solvent-rich region is formed. The polymer-rich region consists of aggregated complexes between the polymeric components bearing similarities to percolated structures met in physical hydrogels. We examine morphological characteristics of the two components as well as the degree of ionic pairing between the different ionic moieties, providing information regarding the degree of physical adsorption of the linear chains on the dendrimer’s surface and that of the respective counterions on the oppositely charged monomers
Self-assembled multivalent RGD-peptide arrays--morphological control and integrin binding
No full textWe report the synthesis of four different RGD peptide derivatives which spontaneously self-assemble into nanoscale architectures. Depending on the information programmed into the molecular-scale building blocks by organic synthesis, these compounds assemble into different nanoscale morphologies. This process can be fully understood using multiscale modelling which provides predictive insight into subtle differences, such as whether the compounds form spherical micelles, rod-like cylinders or tubular assemblies, and predicts experimentally observed critical aggregation concentrations (CACs). We then probe the multivalent binding of these assemblies to integrin proteins and demonstrate that the spherical micellar assemblies perform well in our solution-phase integrin binding assay as a consequence of self-assembled multivalency, with the CAC switching-on the binding. Conversely, the cylindrical assemblies do not work in this assay. As such, the nanoscale morphology controls the apparent ability to perform as a self-assembled multivalent ligand array
Cationic carbosilane dendrimers and oligonucleotide binding: an energetic affair
Full text linkGENERATION 2 CATIONIC CARBOSILANE DENDRIMERS HOLD GREAT PROMISE AS INTERNALIZING AGENTS FOR GENE THERAPY AS THEY PRESENT LOW TOXICITY AND RETAIN AND INTERNALIZE GENETIC MATERIAL AS OLIGONUCLEOTIDE OR SIRNA. IN THIS WORK WE CARRIED OUT A COMPLETE IN SILICO STRUCTURAL AND ENERGETICAL CHARACTERIZATION OF THE INTERACTIONS OF A SET OF 2G CARBOSILANE DENDRIMERS, SHOWING DIFFERENT AFFINITY TOWARDS TWO SINGLE STRAND OLIGONUCLEOTIDE (ODN) SEQUENCES IN VITRO. OUR SIMULATIONS PREDICT THAT THESE FOUR DENDRIMERS AND THE RELEVANT ODN COMPLEXES ARE CHARACTERIZED BY SIMILAR SIZE AND SHAPE, AND THAT THE MOLECULE-SPECIFIC ODN BINDING ABILITY CAN BE RATIONALIZED ONLY CONSIDERING A CRITICAL MOLECULAR DESIGN PARAMETER: THE NORMALIZED EFFECTIVE BINDING ENERGY ΔGBIND,EFF/NEFF I.E., THE PERFORMANCE OF EACH ACTIVE INDIVIDUAL DENDRIMER BRANCH DIRECTLY INVOLVED IN A BINDING INTERACTIO
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