scholarly journals Effect of photoionized plasma and EUV induced surface modification on physico-chemical properties and cytocompatibility of PLLA

2020 ◽  
Vol 14 (11) ◽  
pp. 1063-1077 ◽  
Author(s):  
J. Czwartos ◽  
B. Budner ◽  
A. Bartnik ◽  
W. Kasprzycka ◽  
H. Fiedorowicz
Keyword(s):  
Surface Modification ◽  
Chemical Properties ◽  
Physico Chemical ◽  
Photoionized Plasma

scholarly journals Size and surface modification of silica nanoparticles affect the severity of lung toxicity by modulating endosomal ROS generation in macrophages

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Masahide Inoue ◽  
Koji Sakamoto ◽  
Atsushi Suzuki ◽  
Shinya Nakai ◽  
Akira Ando ◽  
...  
Keyword(s):  
Immune Response ◽  
Surface Modification ◽  
Lung Injury ◽  
Cellular Uptake ◽  
Intratracheal Instillation ◽  
Chemical Properties ◽  
Raw264.7 Cells ◽  
Neutrophilic Infiltration ◽  
Silica Nanomaterials ◽  
Physico Chemical

Abstract Background As the application of silica nanomaterials continues to expand, increasing chances of its exposure to the human body and potential harm are anticipated. Although the toxicity of silica nanomaterials is assumed to be affected by their physio-chemical properties, including size and surface functionalization, its molecular mechanisms remain unclear. We hypothesized that analysis of intracellular localization of the particles and subsequent intracellular signaling could reveal a novel determinant of inflammatory response against silica particles with different physico-chemical properties. Results We employed a murine intratracheal instillation model of amorphous silica nanoparticles (NPs) exposure to compare their in vivo toxicities in the respiratory system. Pristine silica-NPs of 50 nm diameters (50 nm-plain) induced airway-centered lung injury with marked neutrophilic infiltration. By contrast, instillation of pristine silica particles of a larger diameter (3 μm; 3 μm-plain) significantly reduced the severity of lung injury and neutrophilic infiltration, possibly through attenuated induction of neutrophil chemotactic chemokines including MIP2. Ex vivo analysis of alveolar macrophages as well as in vitro assessment using RAW264.7 cells revealed a remarkably lower cellular uptake of 3 μm-plain particles compared with 50 nm-plain, which is assumed to be the underlying mechanism of attenuated immune response. The severity of lung injury and neutrophilic infiltration was also significantly reduced after intratracheal instillation of silica NPs with an amine surface modification (50 nm-NH2) when compared with 50 nm-plain. Despite unchanged efficacy in cellular uptake, treatment with 50 nm-NH2 induced a significantly attenuated immune response in RAW264.7 cells. Assessment of intracellular redox signaling revealed increased reactive oxygen species (ROS) in endosomal compartments of RAW264.7 cells treated with 50 nm-plain when compared with vehicle-treated control. In contrast, augmentation of endosomal ROS signals in cells treated with 50 nm-NH2 was significantly lower. Moreover, selective inhibition of NADPH oxidase 2 (NOX2) was sufficient to inhibit endosomal ROS bursts and induction of chemokine expressions in cells treated with silica NPs, suggesting the central role of endosomal ROS generated by NOX2 in the regulation of the inflammatory response in macrophages that endocytosed silica NPs. Conclusions Our murine model suggested that the pulmonary toxicity of silica NPs depended on their physico-chemical properties through distinct mechanisms. Cellular uptake of larger particles by macrophages decreased, while surface amine modification modulated endosomal ROS signaling via NOX2, both of which are assumed to be involved in mitigating immune response in macrophages and resulting lung injury.

scholarly journals Surface modification of biomaterials using plasma immersion ion implantation and deposition

2012 ◽  
Vol 2 (3) ◽  
pp. 325-336 ◽  
Author(s):  
Tao Lu ◽  
Yuqin Qiao ◽  
Xuanyong Liu
Keyword(s):  
Surface Modification ◽  
Ion Implantation ◽  
Chemical Properties ◽  
Irregular Shapes ◽  
Technical Requirements ◽  
Biological Responses ◽  
Physico Chemical ◽  
Plasma Immersion Ion Implantation ◽  
Cardiovascular Implants ◽  
Remarkable Progress

Although remarkable progress has been made on biomaterial research, the ideal biomaterial that satisfies all the technical requirements and biological functions is not available up to now. Surface modification seems to be a more economic and efficient way to adjust existing conventional biomaterials to meet the current and ever-evolving clinical needs. From an industrial perspective, plasma immersion ion implantation and deposition (PIII&D) is an attractive method for biomaterials owing to its capability of treating objects with irregular shapes, as well as the control of coating composition. It is well acknowledged that the physico-chemical characteristics of biomaterials are the decisive factors greatly affecting the biological responses of biomaterials including bioactivity, haemocompatibility and antibacterial activity. Here, we mainly review the recent advances in surface modification of biomaterials via PIII&D technology, especially titanium alloys and polymers used for orthopaedic, dental and cardiovascular implants. Moreover, the variations of biological performances depending on the physico-chemical properties of modified biomaterials will be discussed.

Influence of surface modification on physico-chemical properties of Ti6Al7Nb alloy

2016 ◽  
Vol 307 ◽  
pp. 753-760 ◽  
Author(s):  
Witold Walke ◽  
Marcin Basiaga ◽  
Zbigniew Paszenda ◽  
Anita Kajzer ◽  
Wojciech Kajzer ◽  
...  
Keyword(s):  
Surface Modification ◽  
Chemical Properties ◽  
Physico Chemical

scholarly journals Nanoparticle Surface Functionalization: How to Improve Biocompatibility and Cellular Internalization

2020 ◽  
Vol 7 ◽  
Author(s):  
Gennaro Sanità ◽  
Barbara Carrese ◽  
Annalisa Lamberti
Keyword(s):  
Surface Modification ◽  
Surface Functionalization ◽  
Surface Composition ◽  
Chemical Properties ◽  
Cellular Internalization ◽  
Key Factors ◽  
Cytotoxic Effects ◽  
Uptake Efficiency ◽  
Nanoparticle Surface ◽  
Physico Chemical

The use of nanoparticles (NP) in diagnosis and treatment of many human diseases, including cancer, is of increasing interest. However, cytotoxic effects of NPs on cells and the uptake efficiency significantly limit their use in clinical practice. The physico-chemical properties of NPs including surface composition, superficial charge, size and shape are considered the key factors that affect the biocompatibility and uptake efficiency of these nanoplatforms. Thanks to the possibility of modifying physico-chemical properties of NPs, it is possible to improve their biocompatibility and uptake efficiency through the functionalization of the NP surface. In this review, we summarize some of the most recent studies in which NP surface modification enhances biocompatibility and uptake. Furthermore, the most used techniques used to assess biocompatibility and uptake are also reported.

Surface Energy of Silica Xerogels and Fumed Silica by Inverse Gas Chromatography and Inverse Liquid Chromatography

2002 ◽  
Vol 75 (5) ◽  
pp. 811-824 ◽  
Author(s):  
J. B. Donnet ◽  
Y. J. Li ◽  
T. K. Wang ◽  
H. Balard ◽  
G. T. Burns
Keyword(s):  
Gas Chromatography ◽  
Surface Modification ◽  
Liquid Chromatography ◽  
Surface Energy ◽  
Fumed Silica ◽  
Inverse Gas Chromatography ◽  
Chemical Properties ◽  
Silica Xerogels ◽  
Silica Surfaces ◽  
Physico Chemical

Abstract Inverse gas chromatography (IGC) and inverse liquid chromatography (ILC) have been used to detect the interaction energy between silicas (fumed silicas and silica xerogels) surfaces and probes molecules. The silica surfaces were modified chemically by trimethylsiloxane functions. Either IGC or ILC have detected the adsorption energy change following the surface modification. In IGC technique, the results with several probes show clearly the physico-chemical properties of the silica surfaces. ILC was developed to use bigger probe molecules which are more similar in structure to polymers. In this work, squalene, a non volatile molecule with 30 carbon atoms and several double bonds, was used in ILC to simulate elastomer molecules.

Decoration of specific sites on freeze-fractured membranes

1978 ◽  
Vol 36 (2) ◽  
pp. 140-141
Author(s):  
H. Gross ◽  
H. Moor
Keyword(s):  
Pure Water ◽  
Freeze Fracture ◽  
Chemical Properties ◽  
Surface Forces ◽  
Sulfate Pentahydrate ◽  
Copper Sulfate Pentahydrate ◽  
Physico Chemical ◽  
Water Of Hydration ◽  
Small Container ◽  
Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

Physico-Chemical Properties of Recombinant Desulphatohirudin

1990 ◽  
Vol 63 (03) ◽  
pp. 499-504 ◽  
Author(s):  
A Electricwala ◽  
L Irons ◽  
R Wait ◽  
R J G Carr ◽  
R J Ling ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Gel Filtration ◽  
Chemical Properties ◽  
Alpha Helix ◽  
Apparent Molecular Weight ◽  
Correlation Spectroscopy ◽  
Nmr Studies ◽  
Recombinant Hirudin ◽  
Physico Chemical ◽  
Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

Physico-chemical properties of the rare-earth metals, scandium, and yttrium

1963 ◽  
Vol 79 (2) ◽  
pp. 263-293 ◽  
Author(s):  
E.M. Savitskii ◽  
V.F. Terekhova ◽  
O.P. Naumkin
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals ◽  
Chemical Properties ◽  
Physico Chemical ◽  
The Rare Earth
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