Search results for " Nanoparticle"
showing 10 items of 936 documents
Optofluidic microconvection with magnetic nanoparticles: Novel interaction of thermal diffusion and magnetic field
2021
Abstract Light-matter interactions are exploited in many applications, whereas superparamagnetic nanoparticles allow to introduce magnetic field control in diverse fluid environments. We study the structure of laser-induced thermal lens in thin layers of ferromagnetic colloid and predict significant magnetoconvective motion around the beam spot. It was found that localized heating depletes/accumulates magnetic nanoparticles in the beam-spot by thermal diffusion and collective magnetic interactions of nanoparticles produce strong microconvective currents. This mode of mass transport can be controlled by magnetic field. We expect the novel magnetosolutal microconvective coupling, which we des…
Carbon Nanodots as Functional Excipient to Develop Highly Stable and Smart PLGA Nanoparticles Useful in Cancer Theranostics
2020
Theranostic systems have attracted considerable attention for their multifunctional approach to cancer. Among these, carbon nanodots (CDs) emerged as luminescent nanomaterials due to their exceptional chemical properties, synthetic ease, biocompatibility, and for their photothermal and fluorescent properties useful in cancer photothermal therapy. However, premature renal excretion due to the small size of these particles limits their biomedical application. To overcome these limitations, here, hybrid poly(lactic-co-glycolic acid) (PLGA-CDs) nanoparticles with suitable size distribution and stability have been developed. CDs were decisive in the preparation of polymeric nanoparticles, not on…
Photoluminescent decoration of iron oxide magnetic nanoparticles for dual-imaging applications
2018
A selective functionalization of dopamine amino group with the photoluminescent 7-nitroben-zofurazan was achieved through a one-pot protection-functionalization-deprotection sequence. The resulting fluorescent catecholic ligand was used as a capping agent for iron oxide nanoparticles thus obtaining photoluminescent magnetic nanoparticles (PL-MNPs). The PL-MNPs were then embedded into PLGA-b-PEG polymeric nanocarriers which quenched the emission of the capping agent. Full recovery of fluorescence was observed after disassembling the polymeric layer of the nanoparticle, thus supporting the use of PL-MNPs as a multifunctional system for targeted drug delivery.
Fluorescence and spin properties of defects in single digit nanodiamonds
2009
International audience; This article reports stable photoluminescence and high-contrast optically detected electron spin resonance (ODESR) from single nitrogen-vacancy (NV) defect centers created within ultrasmall, disperse nanodiamonds of radius less than 4 nm. Unexpectedly, the efficiency for the production of NV fluorescent defects by electron irradiation is found to be independent of the size of the nanocrystals. Fluorescence lifetime imaging shows lifetimes with a mean value of around 17 ns, only slightly longer than the bulk value of the defects. After proper surface cleaning, the dephasing times of the electron spin resonance in the nanocrystals approach values of some microseconds, …
Functional hydrogels containing polyaniline nanoparticles through e-beam irradiation
2009
Antifungal effect of engineered silver nanoparticles on phytopathogenic and toxigenic Fusarium spp. and their impact on mycotoxin accumulation.
2019
Abstract Cereal grains are essential ingredient in food, feed and industrial processing. One of the major causes of cereal spoilage and mycotoxin contamination is the presence of toxigenic Fusarium spp. Nanoparticles have immense applications in agriculture, nutrition, medicine or health but their possible impact on the management of toxigenic fungi and mycotoxins have been very little explored. In this report, the potential of silver nanoparticles (AgNPs) (size 14–100 nm) against the major toxigenic Fusarium spp. affecting crops and their effect on mycotoxin accumulation is evaluated for the first time. The studied Fusarium spp. (and associated mycotoxins) were F. graminearum and F. culmor…
SYNTHESIS AND CHARACTERIZATION OF NEW AMPHIPHILIC COPOLYMERS BASED ON A POLY(HYDROXYETHYL)-D,L-ASPARTAMIDE (PHEA) FOR THE COATING OF GOLD NANOPARTICL…
2012
Polyaspartamide-g-Polylactide graft cpolymers able to form nanoparticles obtained by a novel synthetic strategy.
2009
Impact of gadolinium on the structure and magnetic properties of nanocrystalline powders of iron oxides produced by the extraction-pyrolytic method
2020
The work has been done in frame of the TransFerr project. It has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 778070. This research was also supported by Latvian Research Council project lzp-2018/1-0214. A.I.P. appreciates support from the Estonian Research Council grant (PUT PRG619).
Effect of silver deposits on the photocatalytic activity of titanium dioxide samples for the dehydrogenation or oxidation of 2-propanol
1991
Abstract Until now, the effect of the deposition of metal particles onto a powdered semiconductor oxide on its photocatalytic activity has been determined for group VIII transition metals only. In this study, AGTiO2 samples were prepared by photodeposition, characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) and tested, under band-gap illumination, using the oxidation of 2-propanol (neat liquid phase or mixed with water) in the absence or presence of molecular oxygen. The silver deposits were found to be metallic both before and after use, but the size of the particles and their distribution on the support were markedly influenced by the type …