Effects on the Physical Properties of Ophthalmic Hydrogels Containing 4-Chlorostyrene and Cerium Oxide Nanoparticles with Ultraviolet Blocking Ability

2020 ◽  
Vol 20 (11) ◽  
pp. 6871-6876
Author(s):  
Su-Mi Shin ◽  
A-Young Sung
Keyword(s):  
Thermal Stability ◽  
Physical Properties ◽  
Cerium Oxide ◽  
Breaking Strength ◽  
Cerium Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Uv Blocking ◽  
Cross Linker ◽  
Addition Amount

The optical, physical and polymerization property of hydrogel ophthalmic lenses made by cerium nanoparticles containing 4-chlorostyrene as a base hydrogel material were analyzed. Cerium oxide nanoparticles were used as additive. And HEMA, 4-chlorostyrene and a cross-linker EGDMA were copolymerized in the presence of AIBN as an initiator. Also, the polymerization property such as TGA and absorbance of the prepared lens were measured. Measurement of the polymerization characteristics of the copolymerized material showed that TGA was found that the addition of cerium oxide increased thermal stability. The physical properties of the basic lenses were totally satisfied and breaking strength gradually increased with the addition amount of 4-Chlorostyrene. Cerium nanoparticles are considered to satisfy the basic requirements of hydrogel lenses and UV-blocking amount gradually increased according to the addition ratio of cerium oxide nanoparticles without affecting the basic physical properties. Therefore, these materials can be used effectively as additives for ophthalmic hydrogel lenses.

scholarly journals Poly (Ethylene Glycol) Methyl Ether Methacrylate-Based Hydrogel and Cerium(IV) Oxide Nanoparticles as Ophthalmic Lens Material

Micromachines ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1111
Author(s):  
Min-Jae Lee ◽  
Seon-Young Park ◽  
A-Young Sung
Keyword(s):  
Ethylene Glycol ◽  
Physical Properties ◽  
Cerium Oxide ◽  
Methyl Ether ◽  
Uv Light ◽  
Cerium Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Poly Ethylene Glycol ◽  
Poly Ethylene ◽  
Glycol Methyl Ether

The functional hydrogel lens containing 2-hydroxyethylmethacrylate (HEMA) was manufactured by thermal polymerization. The physical properties of the produced hydrogel lens were measured and analyzed. In this study, HEMA, ethylene glycol dimethacrylate (EGDMA), and azobisisobutyronitrile (AIBN) were used for thermal copolymerization. Additionally, poly (ethylene glycol) methyl ether methacrylate (PEGMEMA), 3-(Triethoxysilyl) propyl isocyanate (TEPI), and cerium(Ⅳ) oxide nanoparticles were used as additives to make a functional hydrogel lens. The mixture was heated at 100 °C for 90 min to produce the hydrogel ophthalmic lens by the cast mold method. The resulting physical properties showed that the water content and refractive index of the sample were in the ranges of 38.06~42.11% and 1.426~1.436, respectively. The addition of cerium oxide nanoparticles lowered the contact angle and allowed the hydrogel lens to block UV light. The tensile strength was also improved by 52.13% through cerium oxide nanoparticles, and up to 123.4% by using TEPI. Based on the results of this study, the produced ophthalmic lens is suitable for durable, UV-blocking high-performance lenses.

Polyacrylic Acid Modified Cerium Oxide Nanoparticles: Synthesis and Characterization as a Peroxidase Mimic for Non-Enzymatic H2O2 Sensor

2020 ◽  
Vol 16 (5) ◽  
pp. 816-828
Author(s):  
Gurdeep Rattu ◽  
Nishtha Khansili ◽  
Prayaga M. Krishna
Keyword(s):  
Hydrogen Peroxide ◽  
Cerium Oxide ◽  
Polyacrylic Acid ◽  
Spectroscopic Analysis ◽  
Cerium Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Peroxidase Mimic ◽  
Ft Ir ◽  
H2o2 Sensing ◽  
Fluorescence Spectrometer

Background: Cerium oxide nanoparticles (nanoceria) are efficient free-radical scavengers due to their dual valence state and thus exhibit optical and catalytic properties. Therefore, the main purpose of this work was to understand the peroxidase mimic activity of polymer-stabilized nanoceria for enzyme-less H2O2 sensing by fluorescence spectrometer. Objective: This research revealed the development of fluorescence hydrogen peroxide nanosensor based on the peroxidase-like activity of polyacrylic acid stabilized nanoceria (PAA-CeO2 Nps). Methods: PAA-CeO2 Nps were synthesized by simple cross-linking reaction at a low temperature and characterized by XRD, SEM, Zeta potential, TGA, FT-IR and UV-VIS spectroscopic analysis. H2O2 sensing was performed by a fluorescence spectrometer. Results:: The synthesized polymer nanocomposite was characterized by XRD, SEM, TGA, FT-IR and UV-VIS spectroscopic analysis. The XRD diffraction patterns confirmed the polycrystalline nature and SEM micrograph showed nanoparticles having hexagonal symmetry and crystallite size of 32 nm. The broad peak of Ce–O bond appeared at 508 cm-1. UV-VIS measurements revealed a welldefined absorbance peak around 315 nm and an optical band-gap of 3.17 eV. As synthesized PAACeO2 Nps effectively catalysed the decomposition of hydrogen peroxide (H2O2) into hydroxyl radicals. Then terephthalic acid was oxidized by hydroxyl radical to form a highly fluorescent product. Under optimized conditions, the linear range for determination of hydrogen peroxide was 0.01 - 0.2 mM with a limit of detection (LOD) of 1.2 μM. Conclusion: The proposed method is ideally suited for the sensing of H2O2 at a low cost and this detection system enabled the sensing of analytes (sugars), which can enzymatically generate hydrogen peroxide.

Radiosensitizing Effect of Cerium Oxide Nanoparticles on Human Leukemia Cells

2018 ◽  
Vol 6 (2) ◽  
pp. 111-115 ◽  
Author(s):  
Azadeh Montazeri ◽  
Zohreh Zal ◽  
Arash Ghasemi ◽  
Hooman Yazdannejat ◽  
Hossein Asgarian-Omran ◽  
...  
Keyword(s):  
Cerium Oxide ◽  
Leukemia Cells ◽  
Cerium Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Human Leukemia ◽  
Radiosensitizing Effect ◽  
Human Leukemia Cells

Cerium oxide nanoparticles acts as a novel therapeutic agent for ulcerative colitis through anti-oxidative mechanism

Life Sciences ◽  
2021 ◽  
pp. 119500
Author(s):  
Fereshteh Asgharzadeh ◽  
Alireza Hashemzadeh ◽  
Farzad Rahmani ◽  
Atieh Yaghoubi ◽  
Seyedeh Elnaz Nazari ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Cerium Oxide ◽  
Therapeutic Agent ◽  
Cerium Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Novel Therapeutic

scholarly journals Influence of Cerium Oxide Nanoparticles on Two Terrestrial Wild Plant Species

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 335
Author(s):  
Daniel Lizzi ◽  
Alessandro Mattiello ◽  
Alessio Adamiano ◽  
Guido Fellet ◽  
Emanuele Gava ◽  
...  
Keyword(s):  
Cerium Oxide ◽  
Plant Species ◽  
Dry Weight ◽  
Wild Plants ◽  
Wild Plant ◽  
Cerium Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Experimental Conditions ◽  
Wild Plant Species ◽  
Leaf Tissues

Most current studies on the relationships between plans and engineered nanomaterials (ENMs) are focused on food crops, while the effects on spontaneous plants have been neglected so far. However, from an ecological perspective, the ENMs impacts on the wild plants could have dire consequences on food webs and ecosystem services. Therefore, they should not be considered less critical. A pot trial was carried out in greenhouse conditions to evaluate the growth of Holcus lanatus L. (monocot) and Diplotaxis tenuifolia L. DC. (dicot) exposed to cerium oxide nanoparticles (nCeO2). Plants were grown for their entire cycle in a substrate amended with 200 mg kg−1nCeO2 having the size of 25 nm and 50 nm, respectively. nCeO2 were taken up by plant roots and then translocated towards leaf tissues of both species. However, the mean size of nCeO2 found in the roots of the species was different. In D. tenuifolia, there was evidence of more significant particle aggregation compared to H. lanatus. Further, biomass variables (dry weight of plant fractions and leaf area) showed that plant species responded differently to the treatments. In the experimental conditions, there were recorded stimulating effects on plant growth. However, nutritional imbalances for macro and micronutrients were observed, as well.

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