Search results for "POLYMERIC"

Biological evaluation of PLLA membranes, with different pore diameters, to stimulate cell adhesion and growth in vitro

2015

Polymeric membranes prepared via DIPS (Diffusion Induced Phase Separation) are widely studied and utilized as scaffolds for the regeneration of tissue. In this work, poly (L)-lactide membrane are prepared through a DIPS protocol starting from a ternary solution made of polymer, dioxane (solvent) and water (non-solvent). A three-dimensional, porous and mechanically stable membrane is desirable for ingrowth of human bronchial epithelial cells. Polymeric membranes prepared via DIPS (Diffusion Induced Phase Separation) are widely studied and utilized as scaffolds for the regeneration of tissue. In this work, poly (L)-lactide membrane are prepared through a DIPS protocol starting from a ternary …

Influence of Bacteria <i>Pseudomonas fluorescens</i> on the Properties of Latvian Clay

2014

Wide varieties of bacteria are able to produce extracellular polymeric substances (EPS) which are mostly composed of polysaccharides. It is suggested that EPS substances can alter certain clay soil properties due to their ability to adhere to the surface of mineral particles. Most common used microorganisms by the researchers for this purpose are of either genus Bacillus or genus Pseudomonas. In this study growth of bacteria P. fluorescens AM PS11 culture in locally obtained clay is studied for the purpose of establishing their influence on rheological properties of clay. An attempt to evaluate it has been made using FT-IR and XRD. Change in plasticity of clay using Atterberg limits method …

Loading of polymer nanocarriers: Factors, mechanisms and applications

2014

Abstract The progress in synthetic polymer chemistry has allowed the precise design of hybrid and multifunctional colloidal particles, which differ in type, size and shape, thus enhancing their possible applications as target-oriented carriers of low and high molar mass active species. This survey discusses the basic principles and factors, associated with the process of loading of polymeric nanoparticles. For the purpose of this review, the polymeric nano-carriers are divided into five most studied types: micelles, nanogels, capsules (incl. vesicles), dendrimers, and hybrid nanoparticles with porous cores. Factors influencing the loading are described and their importance discussed. An imp…

Photooxidation and Stabilization of Photooxidized Polyethylene and of its Monopolymer Blends

2003

The increasing use of products from recycled polymers, or from blends with recycled polymers exposed to the outdoors, implies the need for good weathering resistance. This is particularly important when the recycled material comes, in turn, from products exposed during their lifetime to the sun. In this case the presence of C=O groups in the macromolecular chains strongly increases the photooxidative degradation kinetics of these secondary materials. In this work the change of the photooxidative degradation of blends of virgin and photooxidized polyethylene was evaluated as a function of the C=O content present in the material. As expected, the presence of the C=O groups strongly increases …

Microbial role in dolomitic crust formation associated to Messinian gypsum, Monte Conca cave, Sicily.

2009

Microbial dolomite associated to gypsum stromatolites from a Messinian marginal section, Madonie mountains, Sicily.

2009

Micelles of hyaluronic acid-hexadecylamine derivatives for ocular release of hydrophobic durgs

2016

The topical route is the ideal way to release drugs to the eye. Unfortunately, the low ocular drug bioavailability associated with this route of administration, makes not very efficient the treatment of several ocular diseases. Nowadays, polymeric micelles occupy a significant role in the field of ocular drug delivery thanks to the advantages that they offer in comparison with the administration of drugs in the free form. Indeed, polymeric micelles are suitable for delivering hydrophobic drugs and they seem to be very promising in ocular drug delivery for their high kinetic and thermodynamic stability. Also, micellar systems are able to give a controlled drug release and to act as absorptio…

Water Fluxes in Polymeric Membranes for Desalination via Membrane Distillation

2010

Membrane distillation is an emerging technique for seawater desalination. Hydrophobic polymeric membranes are used to separate the solute‐free water vapour from the hot solution. Vapour fluxes of commercial polymeric membranes were measured in various conditions, i.e. natural and forced convection and vacuum. Vapour fluxes were also predicted with models and compared with experimentals. Higher fluxes were recorded in vacuum conditions.

Microhydrological Niches in Soils: How Mucilage and EPS Alter the Biophysical Properties of the Rhizosphere and Other Biological Hotspots

2019

Plant roots and bacteria are capable of buffering erratic fluctuations of water content in their local soil environment by releasing a diverse, highly polymeric blend of substances (e.g. extracellular polymeric substances [EPS] and mucilage). Although this concept is well accepted, the physical mechanisms by which EPS and mucilage interact with the soil matrix and determine the soil water dynamics remain unclear. High-resolution X-ray computed tomography revealed that upon drying in porous media, mucilage (from maize [Zea mays L.] roots) and EPS (from intact biocrusts) form filaments and two-dimensional interconnected structures spanning across multiple pores. Unlike water, these mucilage a…

Linear biocompatible mannosylated PAAs as potential broad-­‐spectrum microbicides for sexually transmitted diseases

2017

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