Search results for "nanoparticles"
showing 10 items of 1286 documents
Plasmonic nanosensors reveal a height dependence of MinDE protein oscillations on membrane features
2018
6 p.-4 fig.
Onset of cohesion in cement paste
2004
It is generally agreed that the cohesion of cement paste occurs through the formation of a network of nanoparticles of a calcium-silicate-hydrate ("C-S-H"). However, the mechanism by which these particles develop this cohesion has not been established. Here we propose a dielectric continuum model which includes all ionic interactions within a dispersion of C-S-H particles. It takes into account all co-ions and counterions explicitly (with pure Coulomb interactions between ions and between ions and the surfaces) and makes no further assumptions concerning their hydration or their interactions with the surface sites. At high surface charge densities, the model shows that the surface charge of…
Antiviral properties of silver nanoparticles against norovirus surrogates and their efficacy in coated polyhydroxyalkanoates systems
2017
Silver nanoparticles (AgNP) have strong broad-spectrum antimicrobial activity and gained increased attention for the development of AgNP based products, including medical and food applications. Initially, the efficacy of AgNP and silver nitrate (AgNO3) was evaluated for inactivating norovirus surrogates, the feline calicivirus (FCV) and the murine norovirus (MNV). These norovirus surrogates were exposed to AgNO3 and AgNP solutions for 24 h at 25 °C and then analyzed by cell-culture assays. Both AgNP and silver ions significantly decreased FCV and MNV infectivity in a dose-dependent manner between concentrations of 2.1 and 21 mg/L. Furthermore, poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (…
Hybrid Biopolymer and Lipid Nanoparticles with Improved Transfection Efficacy for mRNA
2020
Cells 9(9), 2034 (1-19) (2020). doi:10.3390/cells9092034
TRAIL–NP hybrids for cancer therapy: a review
2017
IF 7.367; International audience; Cancer is a worldwide health problem. It is now considered as a leading cause of morbidity and mortality in developed countries. In the last few decades, considerable progress has been made in anti-cancer therapies, allowing the cure of patients suffering from this disease, or at least helping to prolong their lives. Several cancers, such as those of the lung and pancreas, are still devastating in the absence of therapeutic options. In the early 90s, TRAIL (Tumor Necrosis Factor-related apoptosis-inducing ligand), a cytokine belonging to the TNF superfamily, attracted major interest in oncology owing to its selective anti-tumor properties. Clinical trials u…
Zinc oxide nanoparticles mediated cytotoxicity, mitochondrial membrane potential and level of antioxidants in presence of melatonin.
2017
Zinc oxide nanoparticles (ZnO NPs) are widely used in a variety of products and are currently being investigated for biomedical applications. However, they have the potential to interact with macromolecules like proteins, lipids and DNA within the cells which makes the safe biomedical application difficult. The toxicity of the ZnO NP is mainly attributed reactive oxygen species (ROS) generation. Different strategies like iron doping, polymer coating and external supply of antioxidants have been evaluated to minimize the toxic potential of ZnO NPs. Melatonin is a hormone secreted by the pineal gland with great antioxidant properties. The melatonin is known to protect cells from ROS inducing …
Ochrobactrum sp. MPV1 from a dump of roasted pyrites can be exploited as bacterial catalyst for the biogenesis of selenium and tellurium nanoparticles
2017
Bacteria have developed different mechanisms for the transformation of metalloid oxyanions to non-toxic chemical forms. A number of bacterial isolates so far obtained in axenic culture has shown the ability to bioreduce selenite and tellurite to the elemental state in different conditions along with the formation of nanoparticles—both inside and outside the cells—characterized by a variety of morphological features. This reductive process can be considered of major importance for two reasons: firstly, toxic and soluble (i.e. bioavailable) compounds such as selenite and tellurite are converted to a less toxic chemical forms (i.e. zero valent state); secondly, chalcogen nanoparticles have att…
Biosynthesis of selenium-nanoparticles and -nanorods as a product of selenite bioconversion by the aerobic bacterium Rhodococcus aetherivorans BCP1
2018
The wide anthropogenic use of selenium compounds represents the major source of selenium pollution world- wide, causing environmental issues and health concerns. Microbe-based strategies for metal removal/recovery have received increasing interest thanks to the association of the microbial ability to detoxify toxic metal/ metalloid polluted environments with the production of nanomaterials. This study investigates the tolerance and the bioconversion of selenite (SeO32−) by the aerobically grown Actinomycete Rhodococcus aetherivorans BCP1 in association with its ability to produce selenium nanoparticles and nanorods (SeNPs and SeNRs). The BCP1 strain showed high tolerance towards SeO32− with…
Assembly, growth and conductive properties of tellurium nanorods produced by Rhodococcus aetherivorans BCP1
2018
AbstractTellurite (TeO32−) is a hazardous and toxic oxyanion for living organisms. However, several microorganisms can bioconvert TeO32− into the less toxic form of elemental tellurium (Te0). Here, Rhodococcus aetherivorans BCP1 resting (non-growing) cells showed the proficiency to produce tellurium-based nanoparticles (NPs) and nanorods (NRs) through the bioconversion of TeO32−, depending on the oxyanion initial concentration and time of cellular incubation. Te-nanostructures initially appeared in the cytoplasm of BCP1 cells as spherical NPs, which, as the exposure time increased, were converted into NRs. This observation suggested the existence of an intracellular mechanism of TeNRs assem…
Dextran-based therapeutic nanoparticles for hepatic drug delivery.
2016
Aim: Evaluation of dextran-based nanoparticles (DNP) as a drug delivery system to target myeloid cells of the liver. Materials & methods: DNP were synthesized and optionally PEGylated. Their toxicity and cellular uptake were studied in vitro. Empty and siRNA-carrying DNP were tested in vivo with regard to biodistribution and cellular uptake. Results: In vitro, DNP were taken up by cells of the myeloid lineage without compromising their viability. In vivo, empty and siRNA-carrying DNP distributed to the liver where a single treatment addressed approximately 70% of macrophages and dendritic cells. Serum parameters indicated no in vivo toxicity. Conclusion: DNP are multifunctional liver-s…