Fluorescence from Coated Oxide Nanoparticles

ABSTRACTIn many cases, coated nanoparticles behave like isolated ones. Using the microwave plasma process, it is possible to produce oxide nanoparticles with ceramic or polymer coating. Coating the particles has the additional advantage that by proper selection of the coating it is possible to suspend the particles in distilled water without using any colloid stabilizer. From quantum dots made of sulfides or selenides, it is well known from literature that fluorescence depends strongly on the coating of the kernels. In the case of CdSe, the kernels are coated with CdS. Within this study, similar phenomena are found with coated oxide nanoparticles having sizes of ca. 6 nm exhibiting a very narrow particle size distribution. The coating consists of a second ceramic phase or a polymer one, each one influencing fluorescence differently. Obviously, the type of coating is a tool to modify fluorescence. This behavior is demonstrated on kernels made of Al2O3, ZrO2, HfO2, ZnO etc. PMMA, PTFE, or Al2O3were used as coating material. In most cases, the fluorescence spectra showed broad bands. In some cases, such as ZnO, additionally, a sharp emission line in the UV appears. It is interesting to note that coatings made of fluorine containing polymer materials did not lead to fluorescence intensities comparable with PMMA coatings. The observed spectra are equivalent whether the powder is in aqueous suspensions or dry on a quartz glass carrier. The experimental results in this study indicate that the combination of non-fluorescent oxide core with a non-fluorescent polymer coating may lead to a nanocomposite with strong fluorescence. This is a phenomenon not described in literature until now.

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Stability of Fe-oxide nanoparticles coated with natural organic matter under relevant environmental conditions

Water Science & Technology ◽

10.2166/wst.2014.454 ◽

2014 ◽

Vol 70 (12) ◽

pp. 2040-2046 ◽

Cited By ~ 6

Author(s):

L. Chekli ◽

S. Phuntsho ◽

L. D. Tijing ◽

J. L. Zhou ◽

J.-H. Kim ◽

...

Keyword(s):

Organic Matter ◽

Natural Organic Matter ◽

Environmental Conditions ◽

Divalent Cations ◽

Oxide Nanoparticles ◽

Fe Oxide ◽

Coated Nanoparticles ◽

Aggregation Behaviour ◽

Physico Chemical ◽

The Stability

Manufactured nanoparticles (MNPs) are increasingly released into the environment and thus research on their fate and behaviour in complex environmental samples is urgently needed. The fate of MNPs in the aquatic environment will mainly depend on the physico-chemical characteristics of the medium. The presence and concentration of natural organic matter (NOM) will play a significant role on the stability of MNPs by either decreasing or exacerbating the aggregation phenomenon. In this study, we firstly investigated the effect of NOM concentration on the aggregation behaviour of manufactured Fe-oxide nanoparticles. Then, the stability of the coated nanoparticles was assessed under relevant environmental conditions. Flow field-flow fractionation, an emerging method which is gaining popularity in the field of nanotechnology, has been employed and results have been compared to another size-measurement technique to provide increased confidence in the outcomes. Results showed enhanced stability when the nanoparticles are coated with NOM, which was due to electrosteric stabilisation. However, the presence of divalent cations, even at low concentration (i.e. less than 1 mM) was found to induce aggregation of NOM-coated nanoparticles via bridging mechanisms between NOM and Ca2+.

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Interaction of Carbohydrate Coated Cerium-Oxide Nanoparticles with Wheat and Pea: Stress Induction Potential and Effect on Development

Plants ◽

10.3390/plants8110478 ◽

2019 ◽

Vol 8 (11) ◽

pp. 478 ◽

Cited By ~ 2

Author(s):

Ivana Milenković ◽

Aleksandra Mitrović ◽

Manuel Algarra ◽

Juan M. Lázaro-Martínez ◽

Enrique Rodríguez-Castellón ◽

...

Keyword(s):

Cerium Oxide ◽

Phenolic Content ◽

Positive Impact ◽

Cerium Oxide Nanoparticles ◽

Total Phenolic ◽

Oxide Nanoparticles ◽

Negative Effects ◽

Phenolic Profile ◽

Coated Nanoparticles ◽

Higher Sensitivity

: Reports about the influence of cerium-oxide nanoparticles (nCeO2) on plants are contradictory due to their positive and negative effects on plants. Surface modification may affect the interaction of nCeO2 with the environment, and hence its availability to plants. In this study, the uncoated and glucose-, levan-, and pullulan-coated nCeO2 were synthesized and characterized. The aim was to determine whether nontoxic carbohydrates alter the effect of nCeO2 on the seed germination, plant growth, and metabolism of wheat and pea. We applied 200 mgL-1 of nCeO2 on plants during germination (Ger treatment) or three week-growth (Gro treatment) in hydroponics. The plant response to nCeO2 was studied by measuring changes in Ce concentration, total antioxidative activity (TAA), total phenolic content (TPC), and phenolic profile. Our results generally revealed higher Ce concentration in plants after the treatment with coated nanoparticles compared to uncoated ones. Considering all obtained results, Ger treatment had a stronger impact on the later stages of plant development than Gro treatment. The Ger treatment had a stronger impact on TPC and plant elongation, whereas Gro treatment affected more TAA and phenolic profile. Among nanoparticles, levan-coated nCeO2 had the strongest and positive impact on tested plants. Wheat showed higher sensitivity to all treatments.

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In vitro selection of RNA sequences capable of mediating the formation of iron oxide nanoparticles

Journal of Materials Chemistry ◽

10.1039/b912423c ◽

2009 ◽

Vol 19 (44) ◽

pp. 8320 ◽

Cited By ~ 11

Author(s):

Carly J. Carter ◽

Magda Dolska ◽

Alina Owczarek ◽

Christopher J. Ackerson ◽

Bruce E. Eaton ◽

...

Keyword(s):

Iron Oxide ◽

Iron Oxide Nanoparticles ◽

In Vitro Selection ◽

Oxide Nanoparticles ◽

Rna Sequences ◽

Selection Of

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Functionalization of T lymphocytes for magnetically controlled immune therapy: Selection of suitable superparamagnetic iron oxide nanoparticles

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2018.10.022 ◽

2019 ◽

Vol 473 ◽

pp. 61-67 ◽

Cited By ~ 7

Author(s):

Marina Mühlberger ◽

Christina Janko ◽

Harald Unterweger ◽

Eveline Schreiber ◽

Julia Band ◽

...

Keyword(s):

Iron Oxide ◽

T Lymphocytes ◽

Iron Oxide Nanoparticles ◽

Immune Therapy ◽

Superparamagnetic Iron Oxide ◽

Superparamagnetic Iron Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Selection Of

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Dynamic covalent chemistry in polymer networks: a mechanistic perspective

Polymer Chemistry ◽

10.1039/c9py01260e ◽

2019 ◽

Vol 10 (45) ◽

pp. 6091-6108 ◽

Cited By ~ 81

Author(s):

Johan M. Winne ◽

Ludwik Leibler ◽

Filip E. Du Prez

Keyword(s):

Physicochemical Properties ◽

Reaction Mechanisms ◽

Polymer Networks ◽

Molecular Network ◽

Polymer Materials ◽

Dynamic Covalent Chemistry ◽

Selection Of

A selection of dynamic chemistries is highlighted, with a focus on the reaction mechanisms of molecular network rearrangements, and on how mechanistic profiles can be related to the mechanical and physicochemical properties of polymer materials.

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Selection of Polymer Materials for Micro Slide Bearings With Respect to Minimization of Resistance to Motion

IEEE Access ◽

10.1109/access.2020.2990379 ◽

2020 ◽

Vol 8 ◽

pp. 78622-78629 ◽

Cited By ~ 1

Author(s):

Zbigniew Kusznierewicz ◽

Marcin Michalowski ◽

Sergiusz Luczak ◽

Karol Baginski ◽

Blazej Kabzinski ◽

...

Keyword(s):

Polymer Materials ◽

Selection Of

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Experimental study on T2 relaxation time of protons in water suspensions of iron-oxide nanoparticles: Effects of polymer coating thickness and over-low

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2009.10.013 ◽

2010 ◽

Vol 322 (5) ◽

pp. 548-556 ◽

Cited By ~ 28

Author(s):

D.-X. Chen ◽

N. Sun ◽

Z.-J. Huang ◽

C.-M. Cheng ◽

H. Xu ◽

...

Keyword(s):

Experimental Study ◽

Relaxation Time ◽

Iron Oxide ◽

Iron Oxide Nanoparticles ◽

Coating Thickness ◽

Polymer Coating ◽

Oxide Nanoparticles ◽

T2 Relaxation Time ◽

T2 Relaxation ◽

Water Suspensions

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Some Organic-Inorganic Composites, Illustrative Simulations on Elastomer Reinforcement, and an Overview of Symposium Contributions

MRS Proceedings ◽

10.1557/proc-661-kk1.1 ◽

2000 ◽

Vol 661 ◽

Author(s):

J. E. Mark

Keyword(s):

Sol Gel ◽

Continuous Phase ◽

Polymer Chains ◽

Polymer Materials ◽

General Context ◽

Hydroxyl Groups ◽

Ceramic Phase ◽

Network Chain ◽

Excluded Volume Effects ◽

Inorganic Composites

ABSTRACTThis review first describes organic-inorganic composites which have been prepared using techniques similar to those employed in the new sol-gel approach to ceramics. Organometallics such as silicates, titanates, and aluminates are hydrolyzed in the presence of polymer chains (for example polysiloxanes and polyamides) that typically contain hydroxyl groups. The functional groups are used to bond the polymer chains onto the silica, titania, or alumina being formed in the hydrolysis, thus forming novel organic-inorganic composites. When the polymer chains are present in excess, they constitute the continuous phase, with the ceramic-type material appearing as reinforcing particles. When present in smaller amounts, the polymer is dispersed in the continuous ceramic phase, to give a polymer-modified ceramic. Under some conditions,bicontinuous systems are obtained.The second part addresses one of the major unsolved problems in the area of rubberlike elasticity, specifically a molecular understanding of the mechanisms by which the mechanical properties of elastomers are improved by the incorporation of particulate fillers such as carbon black or silica. Theoretical work on the reinforcement thus obtained is illustrated by some Monte Carlo calculations on one aspect of the problem, namely excluded volume effects of the filler particles on the network chain configurations. The resulting end-to-end distributions are then used in standard molecular models to generate stress-strain isotherms, which document the nature of the reinforcement obtained.The final part provides an overview of the specific papers presented at this symposium, and attempts to place them into the broad general context of “Filled and Nanocomposite Polymer Materials”.

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The use of polymer materials for medical applications

Health and Ecology Issues ◽

10.51523/2708-6011.2020-17-2-1 ◽

2020 ◽

pp. 5-13

Author(s):

D. M. Los' ◽

V. M. Shapovalov ◽

S. V. Zotov

Keyword(s):

Cardiac Surgery ◽

Medical Devices ◽

Metabolic Pathways ◽

Living Organism ◽

Polymer Materials ◽

Medical Applications ◽

Allergic Reactions ◽

Important Criterion ◽

Practical Medicine ◽

Selection Of

The article analyzes the use of polymer materials for solving problems of theoretical and practical medicine. The effectiveness of the use of polymers in reconstructive cardiac surgery, radiation therapy, etc. has been shown. The basic requirements set for polymers and composites for medical devices have been identified. The most important criterion for the selection of polymers is the safety of their use in clinical practice and their ability to biodegrade when they enter a living organism along the usual metabolic pathways in the absence of inflammatory and allergic reactions of surrounding tissues during longterm followup care.

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