Current Physical Chemistry - Volume 4, Issue 2, 2014

Ionic liquids (ILs) are a new generation of molten salts possessing unique physical and chemical properties, which have gained attention from the academic and industries researchers. The design of new products and processes requires the knowledge of transport and thermophysical properties, yet, due to the large number of potential ILs, their characterization by experimental means alone is not feasible. Computer simulations are being used with success for the prediction of structures and properties of many different molecular systems. Among different computational approaches, molecular dynamics simulation (MD) has proved to be capable of providing a good understanding at the molecular level of how the structure and properties of ILs are related. This work reviews the literature and presents an outlook of methodologies applied to predict properties of neat ILs, namely, density, viscosity, diffusivity, melting point, enthalpy of vaporization and surface tension. It has been shown that MD simulations are able to reproduce properties of ILs with good enough accuracy for design purposes. However, lack of force field parameters for several different combinations of ILs and lack of accurate experimental data for some properties of ILs, crucial to calibrate the computational procedures, are some problems that still need to be addressed for a better characterization of the chemical and physical properties of ILs by computer simulation.

In this review, we have investigated study results of recent patents, achievements, and applications of engineered nanoparticles and nanomaterials in nanomedicine. It includes aspects of practical applications of bioconjugated and engineered nanoparticles in medicine and biology for our better life. The methods of innovative drug delivery, diagnosis, treatment, and therapy of diseases are highlighted in novel applications of nanoparticles, nanomaterials, and nanosystems. The main aims of this review are to provide achievements and highlights of patents of recent applications of nanomedicine in the assays in both animal and human. In particular, the engineered nanoparticles of certain size, shape, structure, compositions associated with pharmaceutical compositions show great and promising medical applications, such as gold (Au), silver (Ag), iron (Fe) and platinum (Pt) nanoparticles as well as their compounds in the treatments of various cancers. The new therapies associated with the engineered nanoparticles can improve future cancer therapy protocols. Finally, systems and methods for identifying and evaluating their safety, risk, and toxicity are also discussed in diagnosis, treatment, and therapy of diseases.

Thermo elastic properties of materials at high temperature are directly related to the thermal pressure and volume of expansion of the materials. In the present work we have made a comparative study of temperature dependence of thermal pressure for geophysical minerals viz. MgO, Al2O3, Grossular Garnet, Olivine and Pyrope rich Garnet by using Suzuki formulation and Maxwell’s formulation. It is observed that ΔPTh calculated by using Suzuki formulation is in good agreement with the experimental values up to 800K, but after this limit there is a deviation from experimental values, whereas, in case of Maxwell’s formulation the agreement is valid only upto T=300K. This departure in the agreement has been interpreted using Hardy’s Theory.

The influence and effects that the amino acids L-alanine, glycine and L-proline have on the structure, stability and hydration of lysozyme were analyzed using molecular dynamics (MD) with the CHARMM force field as implemented in the NAMD simulation package. The solution properties of lysozyme in the amino acid-water-protein solutions at room temperature and atmospheric pressure for six concentrations were compared with those of lysozyme in an aqueous solution at the same temperature and pressure. The properties of lysozyme are analyzed in terms of the preferential hydration concept as it applies to the water-protein hydrogen bonds and amino acid-protein hydrogen bonds. The radial distribution functions of the water and amino acid atoms in the neighborhood of lysozyme were used to monitor the preferential hydration. In addition, analysis of the solvent and amino acid atom distributions around lysozyme was used to investigate the make-up/composition of the protein-solution boundary/interface, that is, interfacial waters and/or interfacial amino acid in comparison to the interfacial waters in the protein-water solution. The structure and properties of the amino acids and/or water molecules near the protein surface are also investigated, as they need to be displaced when a ligand, cation, anion or other protein binds and/or interacts with lysozyme. Finally the osmolytic properties of these amino acid/lysozyme solutions in comparison to those of the aqueous lysozyme solution are discussed in terms of the stabilizing effects of lysozyme’s structure in aqueous solution under denaturing conditions: elevated temperature, and on drying, that is, during lyophilization, a common method to stabilize pharmaceutical protein formulations during storage and shipment.

Recently, Sautet et al. (Chem. Rev., 2010, 110, 1788-1806) has given a comprehensive discussion on the surface organometallic species. In this review, a state–of–art understanding will be presented for catalysis of olefin metathesis within zeolites, where the active sites are generally distributed in the nanoscale channels instead of surfaces. It covers the generation of the Mo–carbene active sites from the various olefins, the cross metathesis of ethylene and 2–butylene over these Mo–carbene active sites, the effects of the Mo oxidation state and support acidity as well as the influence of the Al content. More studies are expected for the heterogeneous olefin metathesis such as zeolites, which seems more attractive than the homogeneous counterpart from the industrial point of view.