Search results for " NANOPARTICLES."
showing 7 items of 757 documents
Photobleaching and Recovery Kinetics of a Palette of Carbon Nanodots Probed by In Situ Optical Spectroscopy
2022
Carbon dots (CDs) are a family of fluorescent nanoparticles displaying a wide range of interesting properties, which make them attractive for potential applications in different fields like bioimaging, photocatalysis, and many others. However, despite many years of dedicated studies, wide variations exist in the literature concerning the reported photostability of CDs, and even the photoluminescence mechanism is still unclear. Furthermore, an increasing number of recent studies have highlighted the photobleaching (PB) of CDs under intense UV or visible light beams. PB phenomena need to be fully addressed to optimize practical uses of CDs and can also provide information on the fundamental m…
Polyphenols Epigallocatechin Gallate and Resveratrol, and Polyphenol-Functionalized Nanoparticles Prevent Enterovirus Infection through Clustering an…
2021
To efficiently lower virus infectivity and combat virus epidemics or pandemics, it is important to discover broadly acting antivirals. Here, we investigated two naturally occurring polyphenols, Epigallocatechin gallate (EGCG) and Resveratrol (RES), and polyphenol-functionalized nanoparticles for their antiviral efficacy. Concentrations in the low micromolar range permanently inhibited the infectivity of high doses of enteroviruses (107 PFU/mL). Sucrose gradient separation of radiolabeled viruses, dynamic light scattering, transmission electron microscopic imaging and an in-house developed real-time fluorescence assay revealed that polyphenols prevented infection mainly through clustering of…
Consolidation tests on the graffiti of the Steri’s prison with nanotechnological Ca(OH)2 dispersed in iso-propanol
2009
The combination of weathering and human activities often induce pyhisicochemical alteration on the surface of wall paintings. One of the most still largely used restoration techniques for these works of art, is based on the application of organic polymers. Due to their ability to stick detached and powdered pigments,these products provide an immediate consolidating effects. Unfortunately, both their aging and their pyhisicochemical incompatibility with the inorganic support can have serious consequences also causing further damage to the work of art. In this paper a new technological approach is presented based on the use of Ca(OH)2 nanoparticles dispersed in isopropanol. Some applicative t…
Development of an immunochromatographic assay based on carbon nanoparticles for the determination of the phytoregulator forchlorfenuron
2013
Rapid analytical methods enabling the determination of diverse targets are essential in a number of research areas, from clinical diagnostics to feed and food quality and safety. Herein, the development of a quantitative immunochromatographic assay for the detection of the synthetic phytoregulator forchlorfenuron (CPPU) is described. The competitive lateral flow immunoassay (LFIA) was based on the immobilization onto a nitrocellulose membrane of an ovalbumin-CPPU conjugate (test line) and on the use of an immunodetection ligand consisting of carbon nanoparticles labeled with an anti-CPPU monoclonal antibody through interaction with a secondary antibody. The presence of CPPU in horticultural…
ytterbium nanoparticles: properties, recent synthesis, developments and prespectives
2011
Material science interest is more and more directed to the synthesis and characterization of nano-sized particles. This interest is justified by the fact that the reduction of the particle size of a given material to the nanometer scale causes the rising up of exotic properties that are not present in the bulk state due to size-dependent quantum effects and huge increase of the interfacial species. Further striking features can be gained by controlling nanoparticle shape or through the building up of spatially ordered mono-, bi- and three-dimensional nanoparticle arrays. Then, the wise selection of the nanoparticle synthetic strategy offers the possibility of preparing a wide class of novel…
EVALUATION OF BIODEGRADABILITY ON POLYSPARTAMIDE-POLYLACTIC ACID BASED NANOPARTICLES BY CHEMICAL HYDROLYSIS STUDIES POLYMER DEGRADATION AND STABILITY
2015
Here, the synthesis of two graft copolymers based on α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA) and poly(lactic acid) (PLA), the O-(2-aminoethyl)-O′-galactosyl polyethylene glycol (GAL-PEG-NH2) or the methoxypolyethylene glycol amine (H2N-PEG-OCH3) is described. Starting from the obtained PHEA-PLA-PEG-GAL and PHEA-PLA-PEG copolymers, polymeric nanoparticles were prepared by high pressure homogenization–solvent evaporation method. To demonstrate their biodegradability as a function of the matrix composition, a chemical stability study was carried out until 21 days by incubating systems in two media mimicking physiological compartments (pH 7.4 and pH 5.5). The degradability of both nan…