Université de Fribourg

Preparation of metallosupramolecular single-chain polymeric nanoparticles and their characterization by Taylor dispersion

Neumann, Laura N. ; Urban, Dominic A. ; Lemal, Philipp ; Ramani, Sushila ; Petri-Fink, Alke ; Balog, Sandor ; Weder, Christoph ; Schrettl, Stephen

In: Polymer Chemistry, 2020, vol. 11, no. 2, p. 586–592

Intramolecular cross-linking of polymers can furnish single-chain polymeric nanoparticles (SCPNs), and the use of reversible non-covalent bonds for cross-linking can potentially provide such nanoparticles with stimuli-responsive properties. Here, we report the synthesis of acrylic polymers that carry pendant 2,6-bis(1′-methyl- benzimidazolyl)pyridine ligands, and use these for the...

Université de Fribourg

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

Bossert, David ; Urban, Dominic A. ; Maceroni, Mattia ; Ackermann-Hirschi, Liliane ; Haeni, Laetitia ; Yajan, Phattadon ; Spuch-Calvar, Miguel ; Rothen-Rutishauser, Barbara ; Rodriguez-Lorenzo, Laura ; Petri-Fink, Alke ; Schwab, Fabienne

In: Scientific Reports, 2019, vol. 9, no. 1, p. 7938

As the commercial use of synthetic amorphous silica nanomaterials (SiO2-NPs) increases, their effects on the environment and human health have still not been explored in detail. An often-insurmountable obstacle for SiO2-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...

Université de Fribourg

Nanoparticle administration method in cell culture alters particle-cell interaction

Moore, Thomas L. ; Urban, Dominic A. ; Rodriguez-Lorenzo, Laura ; Milosevic, Ana ; Crippa, Federica ; Spuch-Calvar, Miguel ; Balog, Sandor ; Rothen-Rutishauser, Barbara ; Lattuada, Marco ; Petri-Fink, Alke

In: Scientific Reports, 2019, vol. 9, no. 1, p. 900

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...

Université de Fribourg

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

Durantie, Estelle ; Barosova, Hana ; Drasler, Barbara ; Rodriguez-Lorenzo, Laura ; Urban, Dominic A. ; Vanhecke, Dimitri ; Septiadi, Dedy ; Hirschi-Ackermann, Liliane ; Petri-Fink, Alke ; Rothen-Rutishauser, Barbara

In: Biointerphases, 2018, vol. 13, no. 6, p. 06D404

Inhalation of combustion-derived ultrafine particles (≤0.1 μm) 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...

Université de Fribourg

Taylor dispersion of nanoparticles

Urban, Dominic A. ; Milosevic, Ana M. ; Crippa, Federica ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: Journal of Nanoparticle Research, 2017, vol. 19, no. 8, p. 287

The ability to detect and accurately characterize particles is required by many fields of nanotechnology, including materials science, nanotoxicology, and nanomedicine. Among the most relevant physicochemical properties of nanoparticles, size and the related surface-to-volume ratio are fundamental ones. Taylor dispersion combines three independent phenomena to determine particle size: optical...

Université de Fribourg

Speckle-visibility spectroscopy of depolarized dynamic light scattering

Bossert, David ; Natterodt, Jens ; Urban, Dominic A. ; Weder, Christoph ; Petri-Fink, Alke

In: The Journal of Physical Chemistry B, 2017, vol. 121, no. 33, p. 7999–8007

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...

Université de Fribourg

Lock-in thermography as a rapid and reproducible thermal characterization method for magnetic nanoparticles

Lemal, Philipp ; Geers, Christoph ; Monnier, Christophe A. ; Crippa, Federica ; Daum, Leopold ; Urban, Dominic A. ; Rothen-Rutishauser, Barbara ; Bonmarin, Mathias ; Petri-Fink, Alke

In: Journal of Magnetism and Magnetic Materials, 2017, vol. 427, p. 206–211

Lock-in thermography (LIT) is a sensitive imaging technique generally used in engineering and materials science (e.g. detecting defects in composite materials). However, it has recently been expanded for investigating the heating power of nanomaterials, such as superparamagnetic iron oxide nanoparticles (SPIONs). Here we implement LIT as a rapid and reproducible method that can evaluate the...