Metastable alloy nanoparticles are investigated for their variety of appealing properties exploitable for photonics, magnetism, catalysis and nanobiotechnology. Notably, nanophases out of thermodynamic equilibrium feature a complex "ultrastructure" leading to a dynamic evolution of composition and atomic arrangement in response to physical-chemical stimuli. In this manuscript, metastable Au-Fe alloy nanoparticles were produced by laser ablation in liquid, an emerging versatile synthetic approach for freezing multielement nanosystems in non-equilibrium conditions.
View Article and Find Full Text PDFAccess to detailed information on cells loaded with nanoparticles with nanoscale precision is of a long-standing interest in many areas of nanomedicine. In this context, designing a single experiment able to provide statistical mean data from a large number of living unsectioned cells concerning information on the nanoparticle size and aggregation inside cell endosomes and accurate nanoparticle cell up-take is of paramount importance. Small-angle X-ray scattering (SAXS) is presented here as a tool to achieve such relevant data.
View Article and Find Full Text PDFIn this work, the internalization and distribution of citric acid-coated magnetite nanoparticles (here, FeO-NPs) in soybean and alfalfa tissues and their effects on plant growth were studied. Both legumes were germinated in pots containing an inert growing matrix (vermiculite) to which Hoagland solution without (control, C), with FeO-NPs (50 and 100 mgironL, NP50 and NP100), or with the same amount of soluble iron supplied as Fe-EDTA (Fe50, Fe100) was added once before sowing. Then, plants were watered with the standard nutrient solution.
View Article and Find Full Text PDFThe combination of multiple functions in a single nanoparticle (NP) represents a key advantage of nanomedicine compared to traditional medical approaches. This is well represented by radiotherapy in which the dose of ionizing radiation should be calibrated on sensitizers biodistribution. Ideally, this is possible when the drug acts both as radiation enhancer and imaging contrast agent.
View Article and Find Full Text PDFAppealing physical and chemical properties are foreseen in nanoparticles containing immiscible elements, despite their synthesis is challenging due to the unfavorable thermodynamics. Here we show that silver nanoparticles doped with Co can be achieved by a facile one-step route relying on laser ablation in liquid. Structural analysis suggests that the bimetallic nanoparticles consist of a matrix of face-centred cubic Ag rich of cobalt as point defects or dislocations, in a structure that is stable over time even in aqueous solution.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
February 2021
It is well known that iron oxide magnetic nanoparticles (IONPs) have many potential utilities in biomedicine due to their unique physicochemical properties. With the aim to obtain multifunctional nanoparticles with potential uses for therapy and diagnosis (nanotheranostics), IONPs were synthesized by hydrothermal synthesis assisted by mannose. Two synthetic pathways were evaluated in order to obtain IONPs with suitable properties for biomedical applications.
View Article and Find Full Text PDFSeveral examples of nanosized therapeutic and imaging agents have been proposed to date, yet for most of them there is a low chance of clinical translation due to long-term retention and toxicity risks. The realization of nanoagents that can be removed from the body after use remains thus a great challenge. Here, we demonstrate that nonequilibrium gold-iron alloys behave as shape-morphing nanocrystals with the properties of self-degradable multifunctional nanomedicines.
View Article and Find Full Text PDFMagnetic hyperthermia is an oncological therapy where magnetic nanostructures, under a radiofrequency field, act as heat transducers increasing tumour temperature and killing cancerous cells. Nanostructure heating efficiency depends both on the field conditions and on the nanostructure properties and mobility inside the tumour. Such nanostructures are often incorrectly bench-marketed in the colloidal state and using field settings far off from the recommended therapeutic values.
View Article and Find Full Text PDFMagnetic nanoparticles have attracted much interest due to their broad applications in biomedicine and pollutant remediation. In this work, the optical, magnetic, and structural characteristics of colloids produced by ultrashort pulsed laser ablation of a solid Fe target were studied in four different media: HPLC water, an aqueous solution of trisodium citrate, acetone, and ethanol. Optical extinction spectroscopy revealed an absorption band in the UV region for all, in contrast to the results obtained with nanosecond lasers.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
May 2017
In this study, one-step co-precipitation method was conveniently adapted to obtain novel nanomaterials based on Gum Arabic and magnetite. Two synthesis procedures were evaluated: one employing the solid biopolymer in the co-precipitation media; a second using an aqueous solution of the polysaccharide. An exhaustive characterization of both formulations was performed using several specific techniques.
View Article and Find Full Text PDFMagnetic hyperthermia, a modality that uses radio frequency heating assisted with single-domain magnetic nanoparticles, is becoming established as a powerful oncological therapy. Much improvement in nanomaterials development, to enhance their heating efficiency by tuning the magnetic colloidal properties, has been achieved. However, methodological standardization to accurately and univocally determine the colloidal properties required to numerically reproduce a specific heating efficiency using analytical expressions still holds.
View Article and Find Full Text PDFThe widespread application of surface-enhanced Raman scattering (SERS) would benefit from simple and scalable self-assembly procedures for the realization of plasmonic arrays with a high density of electromagnetic hot-spots. To this aim, the exploitation of iron-doped silver nanoparticles (NPs) synthesized by laser ablation of a bulk bimetallic iron-silver target immersed in ethanol is described. The use of laser ablation in liquid is key to achieving bimetallic NPs in one step with a clean surface available for functionalization with the desired thiolated molecules.
View Article and Find Full Text PDFPhys Rev B Condens Matter
January 1995
Phys Rev B Condens Matter
December 1992
Phys Rev B Condens Matter
October 1992