A hydrofluoric acid-free method to dissolve and quantify silica nanoparticles in aqueous and solid matrices.

As the commercial use of synthetic amorphous silica nanomaterials (SiO-NPs) increases, their effects on the environment and human health have still not been explored in detail. An often-insurmountable obstacle for SiO-NP fate and hazard research is the challenging analytics of solid particulate silica species, which involves toxic and corrosive hydrofluoric acid (HF). We therefore developed and validated a set of simple hydrofluoric acid-free sample preparation methods for the quantification of amorphous SiO micro- and nanoparticles.

Nanoparticle administration method in cell culture alters particle-cell interaction.

As a highly interdisciplinary field, working with nanoparticles in a biomedical context requires a robust understanding of soft matter physics, colloidal behaviors, nano-characterization methods, biology, and bio-nano interactions. When reporting results, it can be easy to overlook simple, seemingly trivial experimental details. In this context, we set out to understand how in vitro technique, specifically the way we administer particles in 2D culture, can influence experimental outcomes.

Carbon nanodots: Opportunities and limitations to study their biodistribution at the human lung epithelial tissue barrier.

Inhalation of combustion-derived ultrafine particles (≤0.1 m) has been found to be associated with pulmonary and cardiovascular diseases. However, correlation of the physicochemical properties of carbon-based particles such as surface charge and agglomeration state with adverse health effects has not yet been established, mainly due to limitations related to the detection of carbon particles in biological environments.

Involvement of two uptake mechanisms of gold and iron oxide nanoparticles in a co-exposure scenario using mouse macrophages.

Little is known about the simultaneous uptake of different engineered nanoparticle types, as it can be expected in our daily life. In order to test such co-exposure effects, murine macrophages (J774A.1 cell line) were incubated with gold (AuNPs) and iron oxide nanoparticles (FeO NPs) either alone or combined.

Speckle-Visibility Spectroscopy of Depolarized Dynamic Light Scattering.

We show that the statistical analysis of photon counts in depolarized dynamic light scattering experiments allows for the accurate characterization of the rotational Brownian dynamics of particles. Unlike photon correlation spectroscopy, the technique is accurate even at low temporal resolution and enables discontinuous data acquisition, which offers several advantages. To demonstrate the usefulness of the method, we present a case study in which we analyze aqueous suspensions of tunicate cellulose nanocrystals and silica particles, and discuss aspects that are specific to particle sizing.

Characterization of hydrophilic coated gold nanoparticles via capillary electrophoresis and Taylor dispersion analysis. Part II: Determination of the hydrodynamic radius distribution - Comparison with asymmetric flow field-flow fractionation.

In the first paper of this series we have shown for hydrophilic coated Au nanoparticles that capillary electrophoresis in combination with Taylor dispersion analysis in fused silica capillaries with an inner diameter of 75 μm allows for the unbiased precise determination of the number-weighted mean hydrodynamic diameter, the zeta potential and the effective charge number, although mobility corrected double layer polarization has to be taken into account. In this second paper we investigate whether the modified approximate analytic expression developed by Ohshima (2001) permits the calculation of calibration lines and the concomitant conversion of electropherograms into number-weighted particle radius distributions. We show that with the method developed size distributions are obtained which are independent of the measurement conditions.

Plasmonic nanoparticles and their characterization in physiological fluids.

Nanoparticles possess unique properties beyond that of classical materials, and while these properties can be used for designing a dedicated functionality, they may also pose a problem to living organisms, to human health and the environment. The specific primary routes by which nanoparticles may interact with the human body include inhalation, injection, ingestion and application to the skin. Independent of the entry route, the particles inevitably encounter a complex physiological fluid populated with e.

Nanoparticle colloidal stability in cell culture media and impact on cellular interactions.

Nanomaterials are finding increasing use for biomedical applications such as imaging, diagnostics, and drug delivery. While it is well understood that nanoparticle (NP) physico-chemical properties can dictate biological responses and interactions, it has been difficult to outline a unifying framework to directly link NP properties to expected in vitro and in vivo outcomes. When introduced to complex biological media containing electrolytes, proteins, lipids, etc.