Search results for "nanoparticle"

Biocompatibility and Antibacterial Properties of ZnO-Incorporated Anodic Oxide Coatings on TiZrNb Alloy

2020

In a present paper, we demonstrate novel approach to form ceramic coatings with incorporated ZnO nanoparticles (NPs) on low modulus TiZrNb alloy with enhanced biocompatibility and antibacterial parameters. Plasma Electrolytic Oxidation (PEO) was used to integrate ZnO nanoparticles (average size 12&ndash

Aluminum tri-isopropoxide as an alternative precursor for atomic layer deposition of aluminum oxide thin films

2019

Due to the safety challenges associated with the use of trimethylaluminum as a metal precursor for the deposition of alumina, different chemicals have been investigated over the years to replace it. The authors have investigated the use of aluminum tri-isopropoxide (TIPA) as an alternative alkoxide precursor for the safe and cost-effective deposition of alumina. In this work, TIPA is used as a stable Al source for atomic layer deposition (ALD) of Al2O3 when different oxidizing agents including water, oxygen plasma, water plasma, and ozone are employed. The authors have explored the deposition of Al2O3 using TIPA in ALD systems operating in vacuum and atmospheric pressure conditions. For the…

Self-Consistent Charge Density-Functional Tight-Binding Parametrization for Pt–Ru Alloys

2017

We present a self-consistent charge density-functional tight-binding (SCC-DFTB) parametrization for PtRu alloys, which is developed by employing a training set of alloy cluster energies and forces obtained from Kohn-Sham density-functional theory (DFT) calculations. Extensive simulations of a testing set of PtRu alloy nanoclusters show that this SCC-DFTB scheme is capable of capturing cluster formation energies with high accuracy relative to DFT calculations. The new SCC-DFTB parametrization is employed within a genetic algorithm to search for global minima of PtRu clusters in the range of 13-81 atoms and the emergence of Ru-core/Pt-shell structures at intermediate alloy compositions, consi…

A Self-Consistent Charge Density-Functional Tight-Binding Parameterization for Pt-Ru Alloys

2017

We present a self-consistent charge density-functional tight-binding (SCC-DFTB) parametrization for PtRu alloys, which is developed by employing a training set of alloy cluster energies and forces obtained from Kohn–Sham density-functional theory (DFT) calculations. Extensive simulations of a testing set of PtRu alloy nanoclusters show that this SCC-DFTB scheme is capable of capturing cluster formation energies with high accuracy relative to DFT calculations. The new SCC-DFTB parametrization is employed within a genetic algorithm to search for global minima of PtRu clusters in the range of 13–81 atoms and the emergence of Ru-core/Pt-shell structures at intermediate alloy compositions, consi…

Hetero-difunctional dimers as building blocks for the synthesis of poly(amidoamine)s with hetero-difunctional chain terminals and their derivatives

2012

This article reports on a simple and straightforward preparation method of poly(amidoamine)s (PAAs) with hetero-difunctional chain ends as well as of several up to now hardly obtainable PAA derivatives of biotechnological interest, such as for instance PAAs of controlled molecular weight and narrow polydispersity mono-functionalized at one end with an acrylamide group, PAAs with star-like molecular architecture, graft-PAA-protein conjugates, “tadpole-like” PAA conjugates with hydrophobic moieties able to self assemble into nanoparticles in aqueous media. The key step was to design suitable building blocks consisting of hetero-difunctional dimers (HDDs). In particular, the HDDs considered we…

DEGRADATION STUDIES OF NOVEL POLYMERIC NANOPARTICLES BASED ON AMPHIPHILIC POLYLACTIC ACID-POLYASPARTAMIDE DERIVATIVES

2014

Acid-Labile Surfactants Based on Poly(ethylene glycol), Carbon Dioxide and Propylene Oxide: Miniemulsion Polymerization and Degradation Studies

2017

Partially degradable, nonionic AB and ABA type di- and triblock copolymers based on poly(propylene carbonate) and poly(ethylene glycol) blocks were synthesized via immortal copolymerization of carbon dioxide and propylene oxide, using mPEG or PEG as a macroinitiator, and (R,R)-(salcy)-CoOBzF5 as a catalyst in a solvent-free one-pot procedure. The amphiphilic surfactants were prepared with molecular weights (Mn) between 2800 and 10,000 g·mol−1 with narrow molecular weight distributions (1.03–1.09). The copolymers were characterized using 1H-, 13C- and DOSY-NMR spectroscopy and size exclusion chromatography (SEC). Surface-active properties were determined by surface tension measurements (crit…

Realization of polyaspartamide-based nanoparticles and in vivo lung biodistribution evaluation of a loaded gucocorticoid after aerosolization in mice

2016

Abstract In this study, novel polymeric nanoparticles (NPs) were developed and their potential as carriers for beclomethasone dipropionate (BDP) into the lung after aerosolization was demonstrated by in vivo studies in mice. In particular, these NPs were obtained starting from two polyaspartamide-based copolymers which were synthesized by chemical reaction of α,β-poly(N-2-hydroxyethyl)- dl -aspartamide (PHEA) and its pegylated derivative (PHEA-PEG2000) with poly(lactic acid) (PLA). To obtain nanosized particles, the high pressure homogenization (HPH)—solvent evaporation method was followed by using an organic phase containing both PHEA-PLA and PHEA-PEG2000-PLA (at a weight ratio equal to 1:…

Protein recovery as a resource from waste specifically via membrane technology : from waste to wonder

2021

Economic growth and the rapid increase in the world population has led to a greater need for natural resources, which in turn, has put pressure on said resources along with the environment. Water, food, and energy, among other resources, pose a huge challenge. Numerous essential resources, including organic substances and valuable nutrients, can be found in wastewater, and these could be recovered with efficient technologies. Protein recovery from waste streams can provide an alternative resource that could be utilized as animal feed. Membrane separation, adsorption, and microbe-assisted protein recovery have been proposed as technologies that could be used for the aforementioned protein re…

Modification of PVDF nanoparticles by controlled free radical graft copolymerization in supercritical carbon dioxide

2014

PVDF (polyvinylidenefluoride) membranes are widely used in microfiltration (MF) and ultrafiltration (UF) due to their excellent processability, chemical resistance, well-controlled porosity, and good thermal properties [1]. Moreover this polymer is also frequently adopted in bio-medical devices owing to its good biocompatibility [2]. On the other hand, the use of PVDF membranes in biomedical applications is limited to some extent by the hydrophobicity of their exposed area, which mainly arises from the nature of the pore surface. Prompted by these considerations in the present work we have studied the modification of PVDF nanoparticles with hydroxyethylmethacrylate (HEMA) thus obtaining a m…