Université de Fribourg

Rapid and sensitive quantification of cell-associated multi-walled carbon nanotubes

Steinmetz, Lukas ; Bourquin, Joel ; Barosova, Hana ; Haeni, Laetitia ; Caldwell, Jessica ; Milosevic, Ana ; Geers, Christoph ; Bonmarin, Mathias ; Taladriz-Blanco, Patricia ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: Nanoscale, 2020, vol. 12, no. 33, p. 17362–17372

Evaluating nanomaterial uptake and association by cells is relevant for in vitro studies related to safe-by-design approaches, nanomedicine or applications in photothermal therapy. However, standard analytical techniques are time-consuming, involve complex sample preparation or include labelling of the investigated sample system with e.g. fluorescent dyes. Here, we explore lock-in...

Université de Fribourg

Simple and fast evaluation of relaxation parameters of magnetic nanoparticles

Lemal, Philipp ; Balog, Sandor ; Ackermann-Hirschi, Liliane ; Taladriz-Blanco, Patricia ; Hirt, Ann M. ; Rothen-Rutishauser, Barbara ; Lattuada, Marco ; Petri-Fink, Alke

In: Journal of Magnetism and Magnetic Materials, 2020, vol. 499, p. 166176

The efficacy of magnetic hyperthermia treatment depends on the optimal available magnetic nanoparticles (MNPs) that are excited in a given alternating magnetic field and viscosity of the region of interest. In this regard, assessing the relevant relaxation parameters is of upmost importance and could improve the speed of development of efficient applications. Here, we demonstrate how to...

Université de Fribourg

Precision of Taylor dispersion

Taladriz-Blanco, Patricia ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke ; Balog, Sandor

In: Analytical Chemistry, 2019, vol. 91, no. 15, p. 9946–9951

Taylor dispersion is capable of measuring accurately the hydrodynamic radius over several orders of magnitude. Accordingly, it is now a highly competitive technique dedicated to characterizing small molecules, proteins, macromolecules, nanoparticles, and their self-assembly. Regardless, an in-depth analysis addressing the precision of the technique, being a key indicator of reproducibility,...

Université de Fribourg

Reduction of nanoparticle load in cells by mitosis but not exocytosis

Bourquin, Joël ; Septiadi, Dedy ; Vanhecke, Dimitri ; Balog, Sandor ; Steinmetz, Lukas ; Spuch-Calvar, Miguel ; Taladriz-Blanco, Patricia ; Petri-Fink, Alke ; Rothen-Rutishauser, Barbara

In: ACS Nano, 2019, vol. 13, no. 7, p. 7759–7770

The long-term fate of biomedically relevant nanoparticles (NPs) at the single cell level after uptake is not fully understood yet. We report that lysosomal exocytosis of NPs is not a mechanism to reduce the particle load. Biopersistent NPs such as nonporous silica and gold remain in cells for a prolonged time. The only reduction of the intracellular NP number is observed via cell division,...

Université de Fribourg

Heating behavior of magnetic iron oxide nanoparticles at clinically relevant concentration

Lemal, Philipp ; Balog, Sandor ; Geers, Christoph ; Taladriz-Blanco, Patricia ; Palumbo, Andrea ; M.Hirt, Ann ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: Journal of Magnetism and Magnetic Materials, 2019, vol. 474, p. 637–642

Magnetic hyperthermia for cancer treatment has gained significant attention in recent years, due to its biocompatibility of applied nanoparticles and the possibility for spatially localized heating in deep tissues. Clinical treatments use nanoparticle concentrations of 112 mg Fe/mL, while the concentrations experimental studies have addressed are considerably smaller, usually between 0.1...