Electron-Beam-Induced Grafting of Chitosan onto HDPE/ATZ Composites for Biomedical Applications

The surface functionalisation of high-density polyethylene (HDPE) and HDPE/alumina-toughened zirconia (ATZ) surfaces with chitosan via electron-beam (EB) irradiation technique was exploited for preparing materials suitable for biomedical purposes. ATR–FTIR analysis and wettability measurements were employed for monitoring the surface changes after both irradiation and chitosan grafting reaction. Interestingly, the presence of ATZ loadings beyond 2 wt% influenced both the EB irradiation process and the chitosan functionalisation reaction, decreasing the oxidation of the surface and the chitosan grafting. The EB irradiation induced an increase in Young’s modulus and a decrease in the elongation at the break of all analysed systems, whereas the tensile strength was not affected in a relevant way. Biological assays indicated that electrostatic interactions between the negative charges of the surface of cell membranes and the –NH3+ sites on chitosan chains promoted cell adhesion, while some oxidised species produced during the irradiation process are thought to cause a detrimental effect on the cell viability.

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Current Research on Polyelectrolyte Nanostructures: From Molecular Interactions to Biomedical Applications

Macromol ◽

10.3390/macromol1020012 ◽

2021 ◽

Vol 1 (2) ◽

pp. 155-172

Author(s):

Aristeidis Papagiannopoulos

Keyword(s):

Physical Properties ◽

Molecular Interactions ◽

Interdisciplinary Research ◽

Biomedical Applications ◽

Electrostatic Interactions ◽

Soft Matter ◽

Extracellular Polysaccharides ◽

Polymer Science ◽

Biological Matter ◽

Biomedical Field

Polyelectrolytes have been at the center of interdisciplinary research for many decades. In the field of polymer science and soft matter, they have provided the dimensions of electrostatic interactions, which opens a vast variety of opportunities for new physical properties and applications. In biological matter, polyelectrolytes are present in many forms, from extracellular polysaccharides to complex DNA molecules and proteins. This review discusses the recent research on polyelectrolytes covering the fundamental level of their conformations and nanostructures, their molecular interactions with materials that have close relevance to bioapplications and their applications in the biomedical field. This approach is motivated by the fact that the polyelectrolyte research is constantly active in all the aforementioned levels and continually affects many critical scientific areas.

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XRD and FTIR analysis of Ti–Si–C–ON coatings for biomedical applications

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2008.06.121 ◽

2008 ◽

Vol 203 (5-7) ◽

pp. 490-494 ◽

Cited By ~ 25

Author(s):

Cristina Oliveira ◽

L. Gonçalves ◽

B.G. Almeida ◽

C.J. Tavares ◽

S. Carvalho ◽

...

Keyword(s):

Biomedical Applications ◽

Ftir Analysis

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A Combination of Hypercholesterolemia and Hypertension Augments an Impairment in Intra-Renal Perfusion Responses

Hypertension ◽

10.1161/hyp.36.suppl_1.712-a ◽

2000 ◽

Vol 36 (suppl_1) ◽

pp. 712-712

Author(s):

Martin G Rodriguez-Porcel ◽

James D Krier ◽

Amir Lerman ◽

Juan C Romero ◽

Lilach O Lerman

Keyword(s):

Risk Factors ◽

Electron Beam ◽

Cardiovascular Risk ◽

Renal Damage ◽

Detrimental Effect ◽

Early Stage ◽

Renal Perfusion ◽

Target Organ ◽

Cholesterol Levels ◽

Electron Beam Ct

P105 The kidney is a target organ for cardiovascular risk factors, such as atherosclerosis and hypertension (HT), and is particularly susceptible to their combination. Even at an early stage, hypercholesterolemia (HC) and HT are individually associated with impaired renal perfusion responses to challenge with vasodilators. However, the effect of combined HC and HT on renal perfusion remains uncertain. To examine this, regional renal perfusion response to the renal vasodilator acetylcholine (Ach) was quantified in 4 groups of pigs, using electron beam CT, after 12 weeks of either normal (n=6), HC diet (n=6), HT (unilateral renal artery stenosis, n=5), or combined HC and HT (HC+HT, n=6). The HC and HC+HT groups had increased cholesterol levels vs. normal and HT (430±82 and 351±52 vs. 71±6 and 83±4 mg/dl, ANOVA p<0.05, respectively). Mean arterial pressure was significantly elevated in HT and HC+HT vs. normal and HC (132±6 and 127±13 vs. 88±5 and 92±6 mmHg, p<0.05, respectively). The combination of HC and HT was associated with a greater impairment in cortical and papillary perfusion responses than HC or HT alone (Table). Medullary perfusion response was not significantly different among the four groups (Table). These results demonstrate that concurrent HC and HT have a greater detrimental effect on renal perfusion responses than HC or HT alone, and that this effect is regionally heterogeneous. These effects may potentially lead to enhanced renal functional impairment and may play a role in the progression of renal damage in HT and atherosclerosis.

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Cyclodextrin-based supramolecular nanoparticles mediated by host-guest and electrostatic interactions: from self-assembly properties to biomedical applications

10.3990/1.9789036541596 ◽

2016 ◽

Author(s):

Laura Grana-Suarez

Keyword(s):

Self Assembly ◽

Biomedical Applications ◽

Electrostatic Interactions ◽

Supramolecular Nanoparticles

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Study on Electron Beam Curing of APTES Functionalized MWNTs/ Epoxy Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.1607 ◽

2011 ◽

Vol 194-196 ◽

pp. 1607-1610

Author(s):

Yan Yan Lu ◽

Hua Li ◽

He Zhou Liu

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Epoxy Resin ◽

Conversion Rate ◽

Epoxy Composites ◽

Pure Epoxy ◽

Gel Content ◽

Electron Beam Curing ◽

Irradiation Process

In this study, we prepared the 3-aminopropyltriethoxysilane (APTES) functionalized MWNTs/epoxy composites by electron beam (EB) irradiation process. The modified MWNTs were characterized with SEM-EDS and FTIR. The gel content and conversion rate of epoxide groups of the EB cured pure epoxy resin and the APTES functionalized MWNTs/epoxy composites were measured and discussed. And the mechanical properties of the EB cured composites were also characterized. With addition of 0.25wt% APTES functionalized MWNTs, the Vicker’s hardness of the EB cured composite increased 100.02% compared with pure epoxy.

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Surface Modification of Gold Nanostars Through the Changes on Gold Seed Concentrations

MRS Advances ◽

10.1557/adv.2018.329 ◽

2018 ◽

Vol 3 (41) ◽

pp. 2449-2454

Author(s):

Juan Carlos Martinez Espinosa ◽

Miguel Jose Yacaman ◽

German Plascencia Villa ◽

Victor Hugo Romero Arellano ◽

Ana Karen Zavala Raya

Keyword(s):

Biomedical Applications ◽

Surface Enhanced Raman Spectroscopy ◽

Diameter Distribution ◽

Biological Assays ◽

Surface Enhanced ◽

Different Types ◽

Surface Enhanced Raman ◽

Gold Seed ◽

Gold Nanomaterials ◽

Specific Membrane

AbstractDue to its excellent optical properties, gold nanomaterials with anisotropic morphology are playing an important role in biomedical applications, specifically in the use of Surface Enhanced Raman Spectroscopy (SERS) technique for biological assays. In this work, we verified the behavior of the star shape nanoparticle peaks obtained by chemical synthesis (precursor reactant: HAuCl4, cationic surfactant: CTAB) and whose peaks were formed from the different concentrations of gold seeds (55, 65, 75 and 85 ul) which were added to the total solution (5.275 ml). The shape and size of the nanoparticles was verified with a Hitachi S-5500 microscope with a BF & DF SEM / STEM detector, and for the diameter distribution (hydrodynamic) was carried out by the dynamic light distribution technique with a Malvern DLS system Zetasizer Nano ZS. Particle sizes (peak-to-peak considering) were obtained with variations from 107 to 166 nm. The results suggest adding 75 ul of gold seeds to obtain uniform nanostars with well defined peaks. These gold nano-stars could be applied for identification of specific membrane markers for the study of different types of cancer by the SERS technique.

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Flame-retardant cotton fabrics modified with phosphoramidate derivative via electron beam irradiation process

Journal of Industrial Textiles ◽

10.1177/1528083719881816 ◽

2019 ◽

pp. 152808371988181

Author(s):

Ying Liu ◽

Li Zhou ◽

Fang Ding ◽

Shanshan Li ◽

Rong Li ◽

...

Keyword(s):

Electron Beam ◽

Flame Retardant ◽

Photoelectron Spectroscopy ◽

Electron Beam Irradiation ◽

Cotton Fabrics ◽

Beam Irradiation ◽

Limiting Oxygen Index ◽

Flammability Test ◽

Lower Temperature ◽

Irradiation Process

In this study, a novel flame-retardant diethyl methacryloylphosphoramidate containing phosphorus and nitrogen was synthesized and characterized by Fourier transform infrared and nuclear magnetic resonance. The synthesized compound was grafted onto cotton fabrics using electron beam irradiation and pad dry cure processes. Scanning electron microscope and X-ray photoelectron spectroscopy were used to characterize the surfaces of the modified cotton fabrics to confirm that diethyl methacryloylphosphoramidate was grafted on cotton fabrics successfully. Both electron beam–cotton and pad dry cure–cotton exhibited efficient flame retardancy which was proved by limiting oxygen index and vertical flammability test. Thermogravimetric analysis results showed that both electron beam-cotton and pad dry cure–cotton degraded at lower temperature and produced higher yields at 600℃. The tensile loss of electron beam–cotton was lower than that of pad dry cure–cotton, and within the acceptable range in flame retardant finishing.

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Nanohydrogels Based on Self-Assembly of Cationic Pullulan and Anionic Dextran Derivatives for Efficient Delivery of Piroxicam

Pharmaceutics ◽

10.3390/pharmaceutics11120622 ◽

2019 ◽

Vol 11 (12) ◽

pp. 622 ◽

Cited By ~ 2

Author(s):

Dorota Lachowicz ◽

Przemyslaw Mielczarek ◽

Roma Wirecka ◽

Katarzyna Berent ◽

Anna Karewicz ◽

...

Keyword(s):

Electron Microscopy ◽

Self Assembly ◽

Electrostatic Interactions ◽

Dextran Sulfate ◽

Force Microscopy ◽

Grafting Reaction ◽

Atomic Force ◽

Transmission Electron ◽

Efficient Delivery ◽

Model Drug

A cationic derivative of pullulan was obtained by grafting reaction and used together with dextran sulfate to form polysaccharide-based nanohydrogel cross-linked via electrostatic interactions between polyions. Due to the polycation-polyanion interactions nanohydrogel particles were formed instantly and spontaneously in water. The nanoparticles were colloidally stable and their size and surface charge could be controlled by the polycation/polyanion ratio. The morphology of the obtained particles was visualized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). The resulting structures were spherical, with hydrodynamic diameters in the range of 100–150 nm. The binding constant (Ka) of a model drug, piroxicam, to the cationic pullulan (C-PUL) was determined by spectrophotometric measurements. The value of Ka was calculated according to the Benesi—Hildebrand equation to be (3.6 ± 0.2) × 103 M−1. After binding to cationic pullulan, piroxicam was effectively entrapped inside the nanohydrogel particles and released in a controlled way. The obtained system was efficiently taken up by cells and was shown to be biocompatible.

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Behavior of nitrogen-related luminescence centers in laser-cut single-crystalline diamond under irradiation with keV electron beam

MRS Advances ◽

10.1557/adv.2017.414 ◽

2017 ◽

Vol 2 (43) ◽

pp. 2355-2360

Author(s):

Kenji Maruoka ◽

Taiki Naito ◽

Osamu Maida ◽

Toshimichi Ito

Keyword(s):

Electron Beam ◽

Nitrogen Atom ◽

Microwave Plasma ◽

Relative Number ◽

Defect States ◽

Single Crystalline ◽

Interstitial Carbon ◽

Luminescence Centers ◽

Irradiation Process ◽

Interstitial Carbon Atom

ABSTRACTWe have found that several nitrogen-related luminescence centers appear at 389 nm, 503 nm (H3 center), 575 nm (NV0 center), 637 nm (NV- center) in single-crystalline Ib diamond cut by means of a YAG laser irradiation process, followed by a suitable hydrogen microwave-plasma treatment, and that cathodoluminescence peaks related to these centers substantially change in intensity by irradiating the sample with 15-keV electron beam (EB). The relative number of 389-nm centers originating from a pair of a substitutional nitrogen atom and an adjacent interstitial carbon atom increased while the concentrations of the vacancy-related centers were reduced with increasing 15-keV EB doses. These facts indicate that both the process-induced self-interstitials and the vacancies in the diamond rather easily moved to more preferential positions to form their stabler defect states, being suggestive of possibility to control densities of NV and NV-related centers.

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