scholarly journals Characterization of Biocompatible Hydrogel Lenses Using Methacrylic Acid with Neodymium Oxide Nanoparticles

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1575
Author(s):  
Min-Jae Lee ◽  
Seon-Young Park ◽  
A-Young Sung
Keyword(s):  
Tensile Strength ◽  
Methacrylic Acid ◽  
Contact Lenses ◽  
Chemical Properties ◽  
Basic Research ◽  
Neodymium Oxide ◽  
Light Transmittance ◽  
Oxide Nanoparticles ◽  
Ph Change ◽  
Safety Level

We prepared hydrogel contact lenses containing nanoparticles of neodymium oxide and methacrylic acid (MA) to investigate their effect on the physical and chemical properties of the lens. Neodymium oxide nanoparticles improved the tensile strength without affecting wettability. The tensile strength, wettability, and light transmittance were all increased when MA was added in a specific ratio. To confirm the safety of the newly used nanoparticles, test on absorbance, eluate, and pH change were conducted and it was found that the safety level was satisfactory. In conclusion, it was confirmed that durable contact lenses can be manufactured with neodymium oxide nanoparticles, and most of the basic elements of the lens such as transparency, strength, and wettability could be improved using MA, which is a hydrophilic material. It is believed that the study will be helpful as part of basic research to use new materials.

The Influence of Microbicidal Components of Essential Oils on the Properties of the Cellulose and Lignocellulose Materials

2016 ◽  
Vol 688 ◽  
pp. 90-95 ◽  
Author(s):  
Ondřej Mikala ◽  
Miloslav Milichovský ◽  
Jan Gojný ◽  
Matěj Hájek
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Essential Oils ◽  
Biological Effects ◽  
Chemical Properties ◽  
Colour Difference ◽  
Ph Change ◽  
Cellulose Materials ◽  
Predetermined Time ◽  
And Chemical Properties

Biological effects of essential oils are investigated for many years. This work is focused on exploring the influence of saturated vapours components of essential oils on the mechanical, optical and chemical properties of cellulose and lignocellulose materials. Diluted vapours of active ingredients of essential oils could be used in future to protect archives made of cellulose materials. For testing were chosen ingredients of essential oils, that showed the highest bactericidal activity. Saturated vapours of these components act on selected cellulose and lignocellulose materials for a predetermined time. From the mechanical properties were measured tensile strength, bending stiffness and compressive strength. Optical properties are represented by the colour difference ∆E and chemical properties by pH change.

scholarly journals Enhanced Tensile Strength of Monolithic Epoxy with Highly Dispersed TiO2-Graphene Nanocomposites

2021 ◽  
Vol 5 (7) ◽  
pp. 191
Author(s):  
Yanshuai Wang ◽  
Siyao Guo ◽  
Biqin Dong ◽  
Feng Xing
Keyword(s):  
Tensile Strength ◽  
Epoxy Resin ◽  
Mechanical Performance ◽  
Chemical Properties ◽  
High Mechanical Property ◽  
Graphene Nanocomposites ◽  
Highly Dispersed ◽  
Dispersion State ◽  
Physical And Chemical

The functionalization of graphene has been reported widely, showing special physical and chemical properties. However, due to the lack of surface functional groups, the poor dispersibility of graphene in solvents strongly limits its engineering applications. This paper develops a novel green “in-situ titania intercalation” method to prepare a highly dispersed graphene, which is enabled by the generation of the titania precursor between the layer of graphene at room temperature to yield titania-graphene nanocomposites (TiO2-RGO). The precursor of titania will produce amounts of nano titania between the graphene interlayers, which can effectively resist the interfacial van der Waals force of the interlamination in graphene for improved dispersion state. Such highly dispersed TiO2-RGO nanocomposites were used to modify epoxy resin. Surprisingly, significant enhancement of the mechanical performance of epoxy resin was observed when incorporating the titania-graphene nanocomposites, especially the improvements in tensile strength and elongation at break, with 75.54% and 176.61% increases at optimal usage compared to the pure epoxy, respectively. The approach presented herein is easy and economical for industry production, which can be potentially applied to the research of high mechanical property graphene/epoxy composite system.

scholarly journals Formulation and Optimization of Sodium Alginate Polymer Film as a Buccal Mucoadhesive Drug Delivery System Containing Cetirizine Dihydrochloride

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 619
Author(s):  
Krisztián Pamlényi ◽  
Katalin Kristó ◽  
Orsolya Jójárt-Laczkovich ◽  
Géza Regdon
Keyword(s):  
Drug Delivery ◽  
Tensile Strength ◽  
Sodium Alginate ◽  
Drug Delivery System ◽  
Delivery System ◽  
Polymer Films ◽  
Hydroxypropyl Methylcellulose ◽  
Chemical Properties ◽  
Active Pharmaceutical Ingredient ◽  
Swallowing Problems

Currently, pharmaceutical companies are working on innovative methods, processes and products. Oral mucoadhesive systems, such as tablets, gels, and polymer films, are among these possible products. Oral mucoadhesive systems possess many advantages, including the possibility to be applied in swallowing problems. The present study focused on formulating buccal mucoadhesive polymer films and investigating the physical and physical–chemical properties of films. Sodium alginate (SA) and hydroxypropyl methylcellulose (HPMC) were used as film-forming agents, glycerol (GLY) was added as a plasticizer, and cetirizine dihydrochloride (CTZ) was used as an active pharmaceutical ingredient (API). The polymer films were prepared at room temperature with the solvent casting method by mixed two-level and three-level factorial designs. The thickness, tensile strength (hardness), mucoadhesivity, surface free energy (SFE), FTIR, and Raman spectra, as well as the dissolution of the prepared films, were investigated. The investigations showed that GLY can reduce the mucoadhesivity of films, and CTZ can increase the tensile strength of films. The distribution of CTZ proved to be homogeneous in the films. The API could dissolve completely from all the films. We can conclude that polymer films with 1% and 3% GLY concentrations are appropriate to be formulated for application on the buccal mucosa as a drug delivery system.

scholarly journals Serial profiling of cell-free DNA and nucleosome histone modifications in cell cultures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vida Ungerer ◽  
Abel J. Bronkhorst ◽  
Priscilla Van den Ackerveken ◽  
Marielle Herzog ◽  
Stefan Holdenrieder
Keyword(s):  
Cancer Cells ◽  
Histone Modifications ◽  
Chemical Properties ◽  
Basic Research ◽  
Live Cells ◽  
Cycle Phase ◽  
Cell Free Dna ◽  
Free Dna ◽  
High Resolution Analysis ◽  
Active Release

AbstractRecent advances in basic research have unveiled several strategies for improving the sensitivity and specificity of cell-free DNA (cfDNA) based assays, which is a prerequisite for broadening its clinical use. Included among these strategies is leveraging knowledge of both the biogenesis and physico-chemical properties of cfDNA towards the identification of better disease-defining features and optimization of methods. While good progress has been made on this front, much of cfDNA biology remains uncharted. Here, we correlated serial measurements of cfDNA size, concentration and nucleosome histone modifications with various cellular parameters, including cell growth rate, viability, apoptosis, necrosis, and cell cycle phase in three different cell lines. Collectively, the picture emerged that temporal changes in cfDNA levels are rather irregular and not the result of constitutive release from live cells. Instead, changes in cfDNA levels correlated with intermittent cell death events, wherein apoptosis contributed more to cfDNA release in non-cancer cells and necrosis more in cancer cells. Interestingly, the presence of a ~ 3 kbp cfDNA population, which is often deemed to originate from accidental cell lysis or active release, was found to originate from necrosis. High-resolution analysis of this cfDNA population revealed an underlying DNA laddering pattern consisting of several oligo-nucleosomes, identical to those generated by apoptosis. This suggests that necrosis may contribute significantly to the pool of mono-nucleosomal cfDNA fragments that are generally interrogated for cancer mutational profiling. Furthermore, since active steps are often taken to exclude longer oligo-nucleosomes from clinical biospecimens and subsequent assays this raises the question of whether important pathological information is lost.

scholarly journals Manufacture of Contact Lens of Nanoparticle-Doped Polymer Complemented with ZEMAX

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 2028
Author(s):  
Lina M. Shaker ◽  
Ahmed A. Al-Amiery ◽  
Abdul Amir H. Kadhum ◽  
Mohd S. Takriff
Keyword(s):  
Contact Lenses ◽  
Titanium Dioxide Nanoparticles ◽  
Optical Design ◽  
Sol Gel ◽  
High Refractive Index ◽  
Light Transmittance ◽  
Great Promise ◽  
Modulation Transfer ◽  
Tio2 Nps ◽  
Molding Method

Many people suffer from myopia or hyperopia due to the refractive errors of the cornea all over the world. The use of high refractive index (RI), Abbe number (νd), and visible light transmittance (T%) polymeric contact lenses (CLs) holds great promise in vision error treatment as an alternative solution to the irreversible laser-assisted in situ keratomileusis (LASIK) surgery. Titanium dioxide nanoparticles (TiO2 NPs) have been suggested as a good candidate to rise the RI and maintain high transparency of a poly(methyl methacrylate) (PMMA)-TiO2 nanocomposite. This work includes a preparation of TiO2 NPs using the sol gel method as well as a synthesis of pure PMMA by free radical polarization and PMMA-TiO2 CLs using a cast molding method of 0.005 and 0.01 w/v concentrations and a study of their effect on the aberrated human eye. ZEMAX optical design software was used for eye modeling based on the Liou and Brennan eye model and then the pure and doped CLs were applied. Ocular performance was evaluated by modulation transfer function (MTF), spot diagram, and image simulation. The used criteria show that the best vision correction was obtained by the CL of higher doping content (p < 0.0001) and that the generated spherical and chromatic aberrations in the eye had been reduced.

Synthesis, characterization and photocatalytic activity of neodymium carbonate and neodymium oxide nanoparticles

2017 ◽  
Vol 1150 ◽  
pp. 411-418 ◽  
Author(s):  
Seied Mahdi Pourmortazavi ◽  
Mehdi Rahimi-Nasrabadi ◽  
Mustafa Aghazadeh ◽  
Mohammad Reza Ganjali ◽  
Meisam Sadeghpour Karimi ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Neodymium Oxide ◽  
Oxide Nanoparticles

scholarly journals Metal Oxide Nanoparticles and their Nanocomposite-based Materials as Photocatalysts in the Degradation of Dyes

2021 ◽  
Vol 12 (5) ◽  
pp. 6557-6579
Keyword(s):  
Metal Oxide ◽  
Anthropogenic Activities ◽  
Metal Oxide Nanoparticles ◽  
Chemical Properties ◽  
Cost Effective ◽  
Oxide Nanoparticles ◽  
Synthetic Dyes ◽  
Characterization Methods ◽  
Degradation Of Dyes ◽  
Physical And Chemical

The introduction of inorganic and organic pollutants into water bodies has become a serious issue globally. The waste streams released from the textile, plastic, leather, paper, pharmaceutical, and food industries introduce different natural and synthetic dyes into the aquatic system. Nanomaterials play a significant role in the photocatalytic degradation of dyes present in wastewater. Inorganic metal oxide nanoparticles have many improved physical and chemical properties and attracted much attention in photocatalytic activities. Dyes have been released in our aquatic bodies due to many anthropogenic activities and caused life-threatening problems. Various conventional methods were reported to remove dyes from water and wastewater; the photocatalytic method is one of the efficient and cost-effective. The present review article includes detailed information on photocatalysis, the potential of metal oxide and their composite materials as photocatalysts in the degradation of toxic dyes, and some common synthetic and characterization methods used for metal oxide-based nanoparticles.

scholarly journals Protein Adsorption: A Feasible Method for Nanoparticle Functionalization?

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 1991 ◽  
Author(s):  
Roberta Cagliani ◽  
Francesca Gatto ◽  
Giuseppe Bardi
Keyword(s):  
Protein Adsorption ◽  
Biological Fluids ◽  
Chemical Properties ◽  
Surface Protein ◽  
Basic Research ◽  
Small Peptides ◽  
Small Proteins ◽  
Corona Formation ◽  
Potential Applications ◽  
Or Gene

Nanomaterials are now well-established components of many sectors of science and technology. Their sizes, structures, and chemical properties allow for the exploration of a vast range of potential applications and novel approaches in basic research. Biomedical applications, such as drug or gene delivery, often require the release of nanoparticles into the bloodstream, which is populated by blood cells and a plethora of small peptides, proteins, sugars, lipids, and complexes of all these molecules. Generally, in biological fluids, a nanoparticle’s surface is covered by different biomolecules, which regulate the interactions of nanoparticles with tissues and, eventually, their fate. The adsorption of molecules onto the nanomaterial is described as “corona” formation. Every blood particulate component can contribute to the creation of the corona, although small proteins represent the majority of the adsorbed chemical moieties. The precise rules of surface-protein adsorption remain unknown, although the surface charge and topography of the nanoparticle seem to discriminate the different coronas. We will describe examples of adsorption of specific biomolecules onto nanoparticles as one of the methods for natural surface functionalization, and highlight advantages and limitations. Our critical review of these topics may help to design appropriate nanomaterials for specific drug delivery.

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